**3.7 Bone marrow disorders**

Non-invasive imaging techniques have been used in the past for visualization the functional activity of the bone marrow compartment. Imaging with radiolabelled compounds may allow different bone marrow disorders to be distinguished. These imaging techniques, almost all of which use radiolabelled tracers, such as 99mTc-nanocolloid, 99mTc-sulphur colloid (99mTc-SC), 111In-chloride, and radiolabelled white blood cells (99mTc-WBC), have been used in nuclear medicine for several decades. The results support that the radiolabelled agents can be alternatives to bone marrow scan.


**2.8 Transformation of vegetable oils to other supramolecular structures**

In addition to the above described wide numbers of supramolecular structures, we also received rubber like, membrane/sheet like and microemulsion structures from vegetable oil under insitu conditions. The following figure depicts the images of rubber like (a), membrane/sheet like (b) and microemulsion structures (c).

Fig. 8. Different supramolecular structures from vegetable oil (a) rubber like; (b) membrane/sheet like; (c) microemulsion structures.

The major differences in the above said three structures are lies with the nature of the vegetable oil chosen. The rubber like material is obtained when the oil is heated near boiling point and then cooled and then incorporated in the mineral medium. The important message obtained from this material preparation is, the whole process is proceeded with out any microbes. Hence, self-assembly would have been takes place by mere self-assembly of the saturated fatty acids.

With reference to membrane/sheet like material and microemulsion structures, marine *Bacillus* sps is involved in the presence of mineral salts.

All these supramolecular structures received from vegetable oils under *in situ* condition during the growth of organisms pose a serious question on whether application of all the microbial products separately without microbes will provide the same kind of materials or not. Thus experiments were conducted separately with the selected oils with the enzyme lipase obtained from Sigma and the biosurfactants separated from the species used in the present study, mineral medium and the environmental conditions like agitation at 180-200 rpm. We received supramolecular structures of vesicles, multilamellar vesicles and selfhealing materials. Other said structures could not be received and implies they will be formed only in the presence of microbes.

The following schematic representation revealed the formation of various supramolecular structures from vegetable oils and the transformation phases observed in the presence and the absence of microbes.

In addition to the above described wide numbers of supramolecular structures, we also received rubber like, membrane/sheet like and microemulsion structures from vegetable oil under insitu conditions. The following figure depicts the images of rubber like (a),

**Rubber like Membrane/sheet like Microemulsion**

**2.8 Transformation of vegetable oils to other supramolecular structures**

membrane/sheet like (b) and microemulsion structures (c).

**a b c**

Fig. 8. Different supramolecular structures from vegetable oil (a) rubber like;

The major differences in the above said three structures are lies with the nature of the vegetable oil chosen. The rubber like material is obtained when the oil is heated near boiling point and then cooled and then incorporated in the mineral medium. The important message obtained from this material preparation is, the whole process is proceeded with out any microbes. Hence, self-assembly would have been takes place by mere self-assembly of

With reference to membrane/sheet like material and microemulsion structures, marine

All these supramolecular structures received from vegetable oils under *in situ* condition during the growth of organisms pose a serious question on whether application of all the microbial products separately without microbes will provide the same kind of materials or not. Thus experiments were conducted separately with the selected oils with the enzyme lipase obtained from Sigma and the biosurfactants separated from the species used in the present study, mineral medium and the environmental conditions like agitation at 180-200 rpm. We received supramolecular structures of vesicles, multilamellar vesicles and selfhealing materials. Other said structures could not be received and implies they will be

The following schematic representation revealed the formation of various supramolecular structures from vegetable oils and the transformation phases observed in the presence and

(b) membrane/sheet like; (c) microemulsion structures.

*Bacillus* sps is involved in the presence of mineral salts.

formed only in the presence of microbes.

the saturated fatty acids.

the absence of microbes.

Fig. 9. Schematic representation of different self-assembled supramoelcular structures using plant triglycerides with microbes, with microbial products and by simple physical treatments.

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**1. Introduction**

The rising level of anti-corruption disclosure has attracted significant attention from state leaders, policymakers, academics, and company stakeholders [1–3]. Corruption may be defined in the simplest terms as the illicit pursuit of personal gain [4], while Transparency International [5] defines corruption as "the misuse of authority for private benefit". Corruption is a global ethical problem with social and economic repercussions, including increasing corporate costs; undermining progress; negatively impacting the quality of life, education, and health systems; as well as increasing poverty and unemployment rates [3,4]. The cost of corruption to governmental organizations, businesses, and individuals is well documented in the literature [6,7]. In the last two decades, bankruptcy and financial scandals involving a variety of organizations have highlighted the prevalence of corruption and its impact [2]. The World Bank (2018) estimates that the various forms of corruption, including bribery, fraud, conflicts of interest, and the falsification of financial statements, cost over US\$ 1 trillion annually. It has been argued that the disclosure of corporate anti-corruption efforts is a useful tool in the battle against corruption [3,8,9].

Whilst it may be possible for individuals or companies in all industrial sectors to find opportunities for corrupt practices, in 2019, the IMF [10] singled out extractive industries as a possible corruption hotspot. Ref. [11] suggested that anti-corruption disclosure (ACD) would be more beneficial for this sector due to its businesses being characterized by high rent-seeking, high investment, and high-risk character. Ref. [12] studied the literature on extractive sector reporting and found a lack of research on the sector's disclosure, providing further motivation for investigating this significant sector.

**Citation:** Ghazwani, M.; Whittington, M.; Helfaya, A. Assessing the Anti-Corruption Disclosure Practices in the UK FTSE 100 Extractive Firms. *Sustainability* **2023**, *15*, 5155. https://doi.org/10.3390/su15065155

Academic Editor: Roberta Costa

Received: 1 February 2023 Revised: 7 March 2023 Accepted: 9 March 2023 Published: 14 March 2023

**Copyright:** © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

Corporate reporting is questioned from a number of perspectives. Financial content has the longest reporting history and the greatest level of oversight and control from authorities. Still, failures of large companies on major stock markets, for example, Enron, Lehman Brothers, and WorldCom show that even the decision-making usefulness of financial reporting could not be relied upon. Recommendations from academics [13] and from professional standard setters such as [14,15] pointed to expanding the scope of what should be reported. This should include not just quantitative financial indicators that are clarified by narrative information but also value-creating factors that are not clearly reflected in financial statements [16,17]. Thus, annual reports should now contain narrative information about a range of factors, including a company's efforts to combat corruption [18,19]. The breadth and depth of information to disclose is a continuing debate. The need for "value relevance," often limited to the shareholder's perspective on value, could be a guiding principle for the decision to disclose non-financial content. However, research has found it difficult to find a clear link between such disclosure and share value [20]. From a broader economic perspective, non-financial disclosures have been found to have little effect on the economy [21,22].

In corporate reporting, anti-corruption disclosures are generally included within the broad category of non-financial disclosures as part of social disclosure, including employee information (gender pay gap, for example), social engagement, and modern slavery reporting. Such corporate ACD purports to inform investors and other stakeholders of a company's commitment to eliminating corruption and promoting transparency and accountability [9]. Conceptual and empirical research has examined corruption from a number of angles—for example, as a concept [23], its origins and consequences [24], its assessment [25], and how to prevent it [26]. Such research can be complicated by differing definitions of corporate corruption and differing requirements across national jurisdictions [9]. Despite these divergent stances, attempts to reduce corruption are generally increasing worldwide (see, for example, [4]).

Such complexity leads us to adopt a case study approach that should have value for wider jurisdictions [27]. This study seeks to investigate ACD within the extractives industry, including oil and gas extraction, focusing on large UK-listed companies. The introduction of the UK Bribery Act (2010) [28] provides an additional focus alongside broader international pressures on ACD from various transnational bodies. To investigate the story of ACD within the UK-listed extractive industry, we will employ metrics that have previously been applied to other areas of non-financial reporting, primarily environmental reporting, which is often significantly more voluminous.

Prior CSR literature has focused on environmental reporting where there is a developing history of significant disclosure running into potentially many pages in an annual report (see, for example, [18,29–32]). This study seeks to apply these measures to ACD, where quantity is much reduced, but it is still important to understand trends, diversity, and depth of corporations. Previous studies show that the choice of metric can lead to differing conclusions on the relative quality of corporate disclosure [30,31,33]. Hence, the FTSE100 extractive companies' anti-corruption disclosures are compared using six measures/indices of reporting quality from the previous environmental accounting research above. The present research divides these measures into two categories (unidimensional measures and compound/multidimensional measures) based on their complexity and dimensionality. There are two "quantity measurements" and one "scope measurement" that are used to measure the information quality in terms of size and coverage of relevant topics, and four compound metrics. The compound metrics have been taken from the literature: the [34] disclosure scoring method (ACHI); [32] quality index of environmental disclosure (SHI); and [35] total quality index (TQLI) [35].

Using a quantitative approach, this study shows that both the design of the quality measurement and the coverage of multiple quality characteristics substantially influence the quality scores and rankings of the sampled extractive firms. It is clear from this data that the quality measures' design impacts the reporting quality ratings [30,35,36]. There are several consequences for a wide range of stakeholders. For both readers and assessors of corporate anti-corruption performance reports, reporting quality is a multifaceted concept covering many features, such as content, credibility, assurance services, and readable content using visual tools. Additionally, the ACD must be credible in order to be accepted by policymakers and standard-setting organizations such as the United Kingdom Bribery Act 2010 and third-party assurance (see, [30,31,37,38]). Anti-corruption reporters and their readers have a trust gap in practice. Thus, a consistent set of ACD guidelines and assurance standards must be established by policymakers, standard setters, and anti-corruption authorities to narrow this gap. Accordingly, the current research aims to answer the following two questions.

**RQ1**. *Can the deployment of reporting quality measures developed in the environmental reporting field enhance our understanding and interpretation of corruption-reporting quality and behavior?*

**RQ2**. *Does the use of these metrics provide consistent evidence that corporate ACD has responded to the introduction of the UK Bribery Act?*

This research is structured as follows. Section 2 presents the literature review, and then Section 3 explains the research methodology. The research findings are discussed in Section 4. Section 5 concludes the study.


**9. Conclusions**

*Geographic Information Systems in Geospatial Intelligence*

**8. Obstacle avoidance navigation systems**

context-aware. More examples can be found in [16].

**8.1 Image processing obstacle avoidance navigation**

A comprehensive automated navigation system must incorporate effective tools for detecting road obstacles and instantly propose the optimal alternate route bypassing the detected obstacle. It combines optimal route finding, real-time route inspection, and route adjustments to ensure safe navigation. The following are three examples utilizing advanced technologies such as computer vision, fuzzy logic, and

Unmanned aerial vehicles (UAVs) use vision as the principal [17] source of information through the monocular onboard camera. The system compares the obtained image to the obstacles to be avoided. Micro aerial vehicle (MAV), to detect and avoid obstacles in an unknown controlled environment. Only the feature points are compared with the same type of contrast, achieving a lower computational cost without reducing the descriptor performance. After detecting the obstacle, the vehicle should recover the path. The algorithm starts when the vehicle is closer to the obstacle than the distance allowed. The limit area value is experimentally obtained defining the dimensions of obstacles in pixels at a specific distance. The output of the control law moves the vehicle away from the center of the obstacle avoiding it. If the error is less than zero, the vehicle moves to the right side.

Detouring of permanent obstacles, a preliminary process is applied to scan the route and correct it such that the corrected route already considers all known obstacles

Mobile robots perform tasks such as rescue and patrolling. It can navigate intelligently by using sensor control techniques [18]. Several techniques have been applied for robot navigation and obstacle avoidance. Fuzzy logic technique is inspired by human perception-based reasoning. It has been applied to behavior-based robot navigation and obstacle avoidance in unknown environments. It trains the robot to navigate by receiving the obstacle distance from a group of sensors. A reinforcement learning method and a genetic algorithm optimize the fuzzy controller for improving its performance while the robot moves. Comparing the performance of different functions such as triangular, trapezoidal, and Gaussian for mobile robot navigation shows that the Gaussian membership function is more efficient for

**8.2 Fuzzy logic technique for mobile robot obstacle avoidance navigation**

A similar concept is using neural network learning method to construct a path planning and collision-free for robots. Real-time collision-free path planning is more difficult when the robot is moving in a dynamic and unstructured

The system is composed of three embedded components; a map manager, a motion tracker, and a hindrance dodging [19]. The map manager generates semantic maps from a given building model. The hindrance dodging detects visible objects lying on the road and suggests a safe bypass route to the target location. A developed prototype performed very well proving that this navigation system is effective

**8.3 Context-aware mobile wearable system with obstacle avoidance**

**24**

and skips them.

navigation.

environment.

and efficient.

This chapter introduces various complementing navigation concepts and implementations, integrating advanced technologies and improving and expanding existing traditional navigation solutions. The outcome is a wide variety of solutions for cases where standard navigation technologies such as GPS are less effective or not applicable. We presented several areas where various technologies have been tailored to specific problems. For each problem we described different cases with unique technologies and implementations.


Meet the editor

Dr. Hasan Sözen is an Assistant Professor in the School of Physical Education and Sport at Ordu University (Ordu, Turkey). His primary research interest includes sport and exercise physiology. Dr. Sözen received his PhD from the Health Science Institute, Department of Physical Education and Sport at Ondokuz Mayıs University (Samsun, Turkey). He completed his post-doctoral fellowship at the Department of Biomedical Sciences for Health

at the University of Milan (Milan, Italy), and his thesis was titled "Electromechanical delay components assessment to disclose age, training status and gender effects on skeletal muscle electromechanical behavior during contraction: new insights from an electromyographic, mechanomyographic and force combined approach". The fellowship was supported by the Scientific and Technological Research Council of Turkey (TUBİTAK).

Contents

Introductory Chapter: Tendons

Tendon Structure and Classification

*by Murat Kaya, Nazım Karahan and Barış Yılmaz*

*by Stephanie C. Torres-Ayala, Alvaro Bravo-Martínez,*

Exercise and Tendon Remodeling Mechanism

Management of Flexor Tendon Injuries in Hand *by Tawheed Ahmad, Summaira Jan and Saima Rashid*

Rabbit Extra-Articular Bone Tunnel Model

*by Kwang-Il Lee, Ju-Woong Jang and Kwang-Won Lee*

Patellar Tendinopathy: "Jumper's Knee" *by Mayur Nayak and Rahul Yadav*

*by Hasan Sözen*

Imaging of Tendons

*and Gracielle Vieira Ramos*

Disease *by Janina Burk*

*by Justin Yousef*

**Preface III**

**Chapter 1 1**

**Chapter 2 5**

**Chapter 3 15**

**Chapter 4 37**

**Chapter 5 57**

**Chapter 6 69** Mechanisms of Action of Multipotent Mesenchymal Stromal Cells in Tendon

**Chapter 7 101**

**Chapter 8 123**

**Chapter 9 139**

Physiology of Flexor Tendon Healing and Rationale for Treatment Protocols

The Injectable rhBMP-2-containing Collagen Gel for Tendon Healing in a

*Amanda P. Marrero-González, Luis R. Rodriguez-Ortíz and Jorge A. Vidal*

*by Rita de Cassia Marqueti, Ivo Vieira de Sousa Neto, Fabricio Reichert Barin*


*1.5.4. Duty cycle*

As duty cycle increases from 10 to 100%, micro-hardness as well as incorporated particles decrease significantly. Lower duty cycle gives longer OFF time for arrival of nanoparticles at the double layer. Therefore, more nanoparticles are reinforced in composite coatings at lower duty cycle and coatings become harder. The improvement in hardness at lower duty cycle is mainly due to grain refinement at pulse OFF-time longer than ON-time.

**Figure 2.** Showing different phases of current density during deposition (a) Pulse direct current with zero current dur‐ ing off time; (b) Superimposed pulse direct current with cathodic current during off-time; (c) Pulse reverse current with anodic current during off time; (d) Pulsed reverse current with combination of zero and anodic current during off time.

**Figure 2: showing different phases of current density during deposition**

### *1.5.5. Bath agitation*

frequency, the content of nanoparticles in composite reduced because the shorter OFF time is not enough to remove concentration gradient of nanoparticles adjacent to the cathode. Wear loss and micro-hardness of composites significantly decreases when pulse frequency increases

By definition, current density is the current per unit surface area of the cathode. It is expressed

Current density actively governs metal deposition and co-deposition process. An increase in current density results in more rapid deposition of the metal matrix and fewer particles are embedded in the coating. To obtain uniform deposition, the current density must be minimal, so that the rate of particles' incorporation into the growing metal will exceed the adsorption on the cathode. Reinforcement of nanoparticles into metal matrix not only restrains the grain growth but also reduces the plastic deformation of metal matrix by combined effect of grain refining and dispersion strengthening, resulting in significant increase in hardness of compo‐

**Direct current** technique is based on the concept that the incorporation of nanoparticles occurs simultaneously with the reduction reaction of an ionic species to form the metal surface. **Pulsed direct current** works on the concept of alternating two or more direct cathodic currents for various deposition times. This allows the incorporation of higher concentrations of nanopar‐ ticles as well as producing a wider range of deposit compositions and properties. **Pulsed reverse current** technique, as the name connotes, has similar characteristics but imposes a cathodic current during the ON time and an anodic current during the OFF time. This method has been the most successful for incorporating higher concentrations of nanoparticles because it helps to eliminate a fraction of the electrodeposited metal during the OFF time. Pulse reverse current technique ensures refine surface microstructure, increased incorporation rate of nanoparticles into the metal deposit and uniform size selective entrapment of particles. During the anodic period, larger sizes of nanoparticles dissolve, whereas smaller nano-particles

As duty cycle increases from 10 to 100%, micro-hardness as well as incorporated particles decrease significantly. Lower duty cycle gives longer OFF time for arrival of nanoparticles at the double layer. Therefore, more nanoparticles are reinforced in composite coatings at lower duty cycle and coatings become harder. The improvement in hardness at lower duty cycle is

mainly due to grain refinement at pulse OFF-time longer than ON-time.

from 10Hz to 1000Hz. Significant adhesive wear is observed at higher frequencies.

*1.5.3. Current density*

42 Electrodeposition of Composite Materials

of surface of the electrode.

The current density can be measured in the following terms:

in *mA* / *cm*2

site coatings.

**•** Direct current

**•** Pulsed direct current **•** Pulsed reverse current.

continue to be entrapped.

*1.5.4. Duty cycle*

**Electrolyte agitation** increases convection of bath contents and therefore enhances the flux of the particles reaching the cathode surface. Intensive agitation may cause adverse effect by disconnection and removal of the particles by turbulent streams of the electrolyte.

Bath agitation serves the purposes of keeping the particles evenly distributed, well suspended in the electrolyte and effectively transported to the cathode surface. Excessive agitation has tendency of removing particles from cathode surface before they can be embedded in the metal deposit. This is due to turbulence initiated by the electrolyte in the bath. 6

For industrial applications, the popular methods used in open tanks include the overhead blade stirrer, the reciprocating plate plunger or a pumped recycle loop of the electrolyte. For laboratory investigations, magnetic stirrers, rotating disk or cylinder electrodes and parallel plate channel flow can be employed. In contrast, the commonly used plate-in-tank geometry provides poorly defined fluid flow conditions.

#### **1.6. Nano-composite Coatings**

The backbone of composite coating is multi-phase union of matrix and second-phase particles in correct ratio. Matrix plays the role of continuous phase and the solvent to disperse the second phase.

**Table 1.** Different types of electrolytic baths

Composite coating can be classified on the basis of the matrix and the reinforcing co-deposited particles. The matrix phase on a broader scale can be grouped into:

The common metals used as matrices for electrolytic co-deposition are: Silver (Ag), Chromium (Cr), Cobalt (Co), Iron (Fe), Zinc (Zn), Nickel (Ni), Copper (Cu) and Gold (Au).

A variety of composite coatings can be deposited by reinforcing different nanoparticles. Reinforcement particles can be carbides (TiC, SiC, WC,Cr2C3)[2,3,4,5,6,7], borides [8], oxides (ZnO, In2O3, ZrO2, CeO2, Al2O3,Cr2O3,SiO2,TiO2) [9,10,11.12], graphite, diamond, or solid lubricants, such as polyethylene and polytetrafluoroethylene [13,14]. Variable amounts of these particles in the coatings become precipitated to impart special properties to the deposited layers. These properties mainly depend on the microstructure of the matrix phase of a composite coating and the amount and distribution of co-deposited particles (non-metallic inclusions) which are influenced by many process parameters.


**6. Dependence of the PL kinetic and energy parameters on structural and dimensional factors**

In the present study, we examined the temperature dependences of the Si QD PL experimentally and observed that the energy radiative transitions are different (**Figures 7** and **8**). It's known that the spectral shift of emission band for QDs is inversely proportional to the square of its radius (Δ*h*ν � *R*�2 ) [1–3, 32, 33]. On the basis of this relationship, we estimate the size of Si QDs, as listed in **Table 2**. The diameter of luminescent QDs is about 3.6–5.4 nm. This assessment is consistent with the previous literature [12].

The high-resolution transmission electron microscopy (HRTEM) shows that when the samples are implanted by Si ions with the fluences between 1.5 � 1017 cm�2 and 1017 cm�2 , the average size of nanocrystal is between 3.8 � 1.2 nm and 3.5 � 1.5 nm, respectively (**Figure 10**). Based on the fact that the radius of exciton in the bulk silicon [3] is about 4.2–4.9 nm, we assume that all the samples are subjected to the effect of strong quantum confinement.

3.The activation barrier *EQ* for the nonradiative relaxation increases (**Figure 12**,

4.The kinetic factors of the intersystem crossing (δ*PISC*) and radiation (δ*PR*) take a maximum value at 1.65 eV for the case of amorphous Si nanoparticles. The intersystem crossing (δ*PISC*) and radiation (δ*PR*) increase for the case of

When the structure of Si QDs is transformed from amorphous to crystalline, a dramatic reduction in the thermal activation characteristics occurs. From **Figure 12** we can see that after crystallization the transition energy parameters (Δ*E*ISC and *E*Q) are significantly reduced. Experimentally, this effect can be observed as the

The right interpretation of the abovementioned key points is impossible without knowledge of system of configuration curves for the emission center. The following reasons can result in the changes of the kinetic parameters and the activation

1.The terms (configuration curves) of exciton are shifted either on the energy

shift of the maximum for the *I*T(*T*) curve from 438 to 158 K (**Figure 8**).

*Temperature Effects in the Photoluminescence of Semiconductor Quantum Dots*

curve 2).

**Figure 11.**

**39**

*(c) 5 1016 cm2*

crystalline Si nanoparticles.

*DOI: http://dx.doi.org/10.5772/intechopen.91888*

barriers for nonradiative transitions:

scale or on the coordinate configuration scale.

*Selected area diffraction (SAD) pattern images; (a) fluence 1.5 1017 cm2*

*, (d) 2 1016 cm2 [12].*

*, (b) 1017 cm2*

*,*

#### **Figure 10.**

*HRTEM images of lattice fringe of SiO2 films (250 nm), implanted by Si-ions; (a) fluence 1.5 1017 cm2 , (b) 1017 cm2 [12].*

However, according to the diffraction data, the nanoparticles differ in size and internal structure. **Figure 11(a)** and **(b)** clearly confirms the presence of Si crystals in samples implanted by ions with fluences A and B; however, SAD does not show any sign of diffraction rings originating from anything but amorphous SiO2 in **Figure 11(c)** and **(d)**. Studies have shown that the PL bands with maxima at 1.8–1.6 eV are found for the amorphous Si nanoparticles, while the emission bands at 1.5–1.43 eV are related with the crystalline Si nanoparticles [4, 5, 10, 12]. Consequently, the change in the size, morphology, and structural ordering of QDs strongly affects the dependence of PL temperature curves on the ion fluence. In addition, the disorder degree in atomic structure and position of emission bands heavily depend on the size of QDs.

The form of the PL quenching curves is determined by the activation barriers and frequency factors, which are strongly affected by the all abovementioned factors (**Figures 7** and **8**).

The analysis of physical properties of the PL of Si QDs was performed on the basis of the data listed in **Table 2**. So, when the size of QDs increases:

*Temperature Effects in the Photoluminescence of Semiconductor Quantum Dots DOI: http://dx.doi.org/10.5772/intechopen.91888*

When the structure of Si QDs is transformed from amorphous to crystalline, a dramatic reduction in the thermal activation characteristics occurs. From **Figure 12** we can see that after crystallization the transition energy parameters (Δ*E*ISC and *E*Q) are significantly reduced. Experimentally, this effect can be observed as the shift of the maximum for the *I*T(*T*) curve from 438 to 158 K (**Figure 8**).

The right interpretation of the abovementioned key points is impossible without knowledge of system of configuration curves for the emission center. The following reasons can result in the changes of the kinetic parameters and the activation barriers for nonradiative transitions:

1.The terms (configuration curves) of exciton are shifted either on the energy scale or on the coordinate configuration scale.

#### **Figure 11.**

*Selected area diffraction (SAD) pattern images; (a) fluence 1.5 1017 cm2 , (b) 1017 cm2 , (c) 5 1016 cm2 , (d) 2 1016 cm2 [12].*

However, according to the diffraction data, the nanoparticles differ in size and internal structure. **Figure 11(a)** and **(b)** clearly confirms the presence of Si crystals in samples implanted by ions with fluences A and B; however, SAD does not show any sign of diffraction rings originating from anything but amorphous SiO2 in **Figure 11(c)** and **(d)**. Studies have shown that the PL bands with maxima at 1.8–1.6 eV are found for the amorphous Si nanoparticles, while the emission bands at 1.5–1.43 eV are related with the crystalline Si nanoparticles [4, 5, 10, 12]. Consequently, the change in the size, morphology, and structural ordering of QDs strongly affects the dependence of PL temperature curves on the ion fluence. In addition, the disorder degree in atomic structure and position of emission bands

*,*

*HRTEM images of lattice fringe of SiO2 films (250 nm), implanted by Si-ions; (a) fluence 1.5 1017 cm2*

The form of the PL quenching curves is determined by the activation barriers and frequency factors, which are strongly affected by the all abovementioned

The analysis of physical properties of the PL of Si QDs was performed on the

2.The value of parameter Δ*E*ISC corresponding to the intersystem crossing of

1.The extremum of the PL quenching curve shifts to the range of higher

basis of the data listed in **Table 2**. So, when the size of QDs increases:

excitons increases (**Figure 12**, curve 1).

heavily depend on the size of QDs.

*Quantum Dots - Fundamental and Applications*

factors (**Figures 7** and **8**).

**Figure 10.**

*(b) 1017 cm2 [12].*

temperatures.

**38**

#### **Figure 12.**

*The relationship between the energies of radiative PL transitions and the activation parameters of nonradiative transitions in silicon QDs in crystalline and amorphous state, which shows their dependence on structural and dimensional factors. The energy factor of the intercombining conversion is designated as* E*ISC, and the thermally activated barrier of PL quenching is* E*Q. the filled circles show the results of the data presented in [4, 5, 10, 13] and the open circles [12, 13].*

A system of hypothetical configuration curves with the terms of singlet ground state S0 and terms of singlet and triplet excited states (S1 and T1, respectively) is shown in **Figure 13**. For clarity, the distribution of terms caused by the continual disorder isn't shown. It is assumed that the parameters Δ*E*ISC and *E*Q take some effective values, which correspond to the maxima of distribution functions.

The main observation of the reduction in size of nanoparticles is the increase of the optical transitions energy, owing to the shift of the terms relative to each other [1–3]. We assume that S0, S1, and T1 have a parabolic form; we can see that the shift of S1 to the position of S1' will lead to a decrease in the energy factor Δ *E*ISC of the intersystem crossing (see **Figure 13a**).

This is well consistent with the curve 1 of **Figure 12**. However, a similar shift of the position for T1 toward T1' (**Figure 13b**) implies that increasing the energy of the radiative transition (*h*ν) will increase the activation barrier (*E*Q'). At the same time, according to the experimental results (see **Figure 12**, curve 2), this barrier has to be decreased. **Figure 12** shows that this contradiction can be solved if the displacement of T1 is accompanied by its extension (T1"). This effect corresponds to the decrease of the frequency factor *p*05 and kinetic factor δ*P*R where the approximation results confirm the increasing of the energy of radiative transition (**Table 2**).

is a sharp decrease in activation barriers at transition from amorphous to crystalline QDs. From this point of view, the structural disorder is becoming a negligible factor. On the other hand, the dependence of shift and broadening of the configuration curves on the QD size also are observed for the case of crystalline QDs. **Table 2** shows that the energy and the kinetic parameters of nonradiative transi-

*Schematic illustration of the change in the energy factor Δ*EISC *of intercombination conversion (a) and the activation barrier* E*Q of the PL quenching (b) with a decrease in the size of quantum dots. The figure shows the initial terms of the ground and excited triplet and singlet states (S0,T1, S1), the displaced terms of the excited triplet and singlet states (T1', S1'), and the shifted and broadened term of the excited triplet state (T1").*

*Temperature Effects in the Photoluminescence of Semiconductor Quantum Dots*

*DOI: http://dx.doi.org/10.5772/intechopen.91888*

The effect on structural and dimensional factors on the activation parameters of the radiative and nonradiative relaxations can be estimated from the three-level system of QD luminescence (**Figure 13**). However, for this task it is necessary to conduct special experiments and theoretical modeling (ab initio calculations). This

The developed ideas are a powerful tool for the control of the optical properties of QDs depending on the size, composition, and structure factors. We believe, the proposed approach is universal and can be applied to semiconductor QDs (such as Si, Ge, C) in dielectric hosts. The estimation of the applicability of this model to QDs of another type (e.g., with complex composition or special structural features

tions depend on the size of QDs.

**Figure 13.**

**41**

issue is outside the scope of this work.

[34]) can be performed using a special experimental check.

The abovementioned four key points were found experimentally [4, 5, 12, 13]. There is a red shift of emission bands from 1.8 to 1.4 eV with an increasing of QD size. In addition, the PL band broadening is observed (0.15–0.4 eV), which can be caused by the broadening of the configuration curve for the T1 excited triplet state (**Figure 13b**).

In the case of amorphous nanoparticles (**Figure 12**), the increase of the effective parameters Δ*E*ISC and *E*Q in a larger QD size can be due to the variations in the corresponding distribution functions of energy levels. Since the size effect in the amorphous nanoparticles manifests itself more strongly in comparison with the crystalline nanoparticles, we can assume the quite importance of the continual disordering in the formation of QD optical properties. It should be noted that there

*Temperature Effects in the Photoluminescence of Semiconductor Quantum Dots DOI: http://dx.doi.org/10.5772/intechopen.91888*

#### **Figure 13.**

2.The broadening or narrowing of configuration curves is observed.

configuration curves on the energy and configuration scales.

confirm the increasing of the energy of radiative transition (**Table 2**).

intersystem crossing (see **Figure 13a**).

(**Figure 13b**).

**40**

**Figure 12.**

*and the open circles [12, 13].*

*Quantum Dots - Fundamental and Applications*

3.The changes in the degree of continual disorder result in the distribution of

*The relationship between the energies of radiative PL transitions and the activation parameters of nonradiative transitions in silicon QDs in crystalline and amorphous state, which shows their dependence on structural and dimensional factors. The energy factor of the intercombining conversion is designated as* E*ISC, and the thermally activated barrier of PL quenching is* E*Q. the filled circles show the results of the data presented in [4, 5, 10, 13]*

A system of hypothetical configuration curves with the terms of singlet ground state S0 and terms of singlet and triplet excited states (S1 and T1, respectively) is shown in **Figure 13**. For clarity, the distribution of terms caused by the continual disorder isn't shown. It is assumed that the parameters Δ*E*ISC and *E*Q take some effective values, which correspond to the maxima of distribution functions.

The main observation of the reduction in size of nanoparticles is the increase of the optical transitions energy, owing to the shift of the terms relative to each other [1–3]. We assume that S0, S1, and T1 have a parabolic form; we can see that the shift of S1 to the position of S1' will lead to a decrease in the energy factor Δ *E*ISC of the

This is well consistent with the curve 1 of **Figure 12**. However, a similar shift of the position for T1 toward T1' (**Figure 13b**) implies that increasing the energy of the radiative transition (*h*ν) will increase the activation barrier (*E*Q'). At the same time, according to the experimental results (see **Figure 12**, curve 2), this barrier has to be decreased. **Figure 12** shows that this contradiction can be solved if the displacement of T1 is accompanied by its extension (T1"). This effect corresponds to the decrease of the frequency factor *p*05 and kinetic factor δ*P*R where the approximation results

The abovementioned four key points were found experimentally [4, 5, 12, 13]. There is a red shift of emission bands from 1.8 to 1.4 eV with an increasing of QD size. In addition, the PL band broadening is observed (0.15–0.4 eV), which can be caused by the broadening of the configuration curve for the T1 excited triplet state

In the case of amorphous nanoparticles (**Figure 12**), the increase of the effective

parameters Δ*E*ISC and *E*Q in a larger QD size can be due to the variations in the corresponding distribution functions of energy levels. Since the size effect in the amorphous nanoparticles manifests itself more strongly in comparison with the crystalline nanoparticles, we can assume the quite importance of the continual disordering in the formation of QD optical properties. It should be noted that there *Schematic illustration of the change in the energy factor Δ*EISC *of intercombination conversion (a) and the activation barrier* E*Q of the PL quenching (b) with a decrease in the size of quantum dots. The figure shows the initial terms of the ground and excited triplet and singlet states (S0,T1, S1), the displaced terms of the excited triplet and singlet states (T1', S1'), and the shifted and broadened term of the excited triplet state (T1").*

is a sharp decrease in activation barriers at transition from amorphous to crystalline QDs. From this point of view, the structural disorder is becoming a negligible factor. On the other hand, the dependence of shift and broadening of the configuration curves on the QD size also are observed for the case of crystalline QDs. **Table 2** shows that the energy and the kinetic parameters of nonradiative transitions depend on the size of QDs.

The effect on structural and dimensional factors on the activation parameters of the radiative and nonradiative relaxations can be estimated from the three-level system of QD luminescence (**Figure 13**). However, for this task it is necessary to conduct special experiments and theoretical modeling (ab initio calculations). This issue is outside the scope of this work.

The developed ideas are a powerful tool for the control of the optical properties of QDs depending on the size, composition, and structure factors. We believe, the proposed approach is universal and can be applied to semiconductor QDs (such as Si, Ge, C) in dielectric hosts. The estimation of the applicability of this model to QDs of another type (e.g., with complex composition or special structural features [34]) can be performed using a special experimental check.


Progress in Fine Particle Plasmas

*Edited by Tetsu Mieno, Yasuaki Hayashi and Kun Xue*

Published in London, United Kingdom

## *Supporting open minds since 2005*

Progress in Fine Particle Plasmas http://dx.doi.org/10.5772/intechopen.83211 Edited by Tetsu Mieno, Yasuaki Hayashi and Kun Xue

#### Contributors

Junsheng Zeng, Sandip Hasuram Gharat, Akio Sanpei, Kazuo Takahashi, Yasuhito Matsubayashi, Noritaka Sakakibara, Tsuyohito Ito, Kazuo Terashima, Hiroo Totsuji, Viktor Gerasimenko, Yoshifumi Saitou, Osamu Ishihara, Yasuaki Hayashi, Ravinder Goyal, R P Sharma, Gheorghe Dinescu, Tomy Acsente, Lavinia Gabriela Carpen, Elena Matei, Christian Grisolia, Bogdan Bita, Raluca Negrea, Elodie Bernard, Jorge Enrique García-Farieta, Rigoberto Casas, Heng Li

#### © The Editor(s) and the Author(s) 2020

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First published in London, United Kingdom, 2020 by IntechOpen IntechOpen is the global imprint of INTECHOPEN LIMITED, registered in England and Wales, registration number: 11086078, 5 Princes Gate Court, London, SW7 2QJ, United Kingdom Printed in Croatia

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**3. Food packaging materials**

The aim when the food is packaged mostly is to be safely transported and correctly stored. The proper combination of packaging materials and technologies ensures that product quality and freshness are maintained during distribution and storage. Package design and structure are important considerations. That is, not only a container, but it must also protect what it sells and sell what it protects [9]. One of the most important aspects of packaging from a business standpoint is that it identifies the appearance of the product in the distribution chain and distinguishes it when reaching the consumer. Today's food packaging frequently combines several materials to take advantage of each material's functional or esthetic properties. Advances in the field of food packaging research may have an impact on the environment as it continues. Aside from food preservation, current techniques are focused on two extra goals: the suitability of the materials used and the generation of eco-friendly products with no presence of side effects on health.

Food packaging materials that have traditionally been used include wood, paper, and polymers, to most new biocomposites. Plastics do not fare well, but neither do wood or paper. However, there is a shift in demand, which makes biocomposites the finest among all [19].


**6. Conclusions**

In this review, we examined a key finding, recently reported by Fàbregas and colleagues [2], in which an increased expression of the BRL3 receptor provided resistance to a lack of water but did not impair plant development. Such cases, in relation to any stress, are quite rare, since resistance to any stressful condition is usually accompanied by growth retardation. Drought tolerance of plants is controlled by numerous signaling modules forming a branched network of protein–protein interactions. In this study, we examined all known interactions of the BR and ABA signaling pathways, but left out the signaling pathways of gibberellins and the light signaling system, which undoubtedly a ffect stress tolerance, but would greatly complicate the understanding of the described phenomenon.

In such cases as the one that was described by Fàbregas et al. [2], we should look for adaptation processes caused by memory generation. Ding et al. [39] postulated that under natural conditions, stress memory is activated by the previous dehydration stress, continues during the recovery period, and prepares the plant's response to the next dehydration stress. This is surprising, but so far the

BR pathway has not been extensively studied with respect to epigenetic changes and the generation of stress memory, and only the first steps have been taken on this path [45–47,68,71]. For the closest animal relatives of BRs, glucocorticoids, we observe an extensive field of research related specifically to changes in chromatin structure [72]. At present, it is still unclear whether BRs have a lesser e ffect on adaptive chromatin rearrangements or if they are simply underexplored in this regard.

We hypothesized that BRs may be involved in stress acclimation by three interconnected mechanisms. The first mechanism is that the signal passes through the module BRL3 (or BRI1) → BSK1/3 → BSU1 — BIN2 → BSK1/3, in which BIN2 is responsible for communication with ABA signaling and the BSK proteins serve as signal concentrators. The second mechanism is priming through chromatin modifications, in which BRL3 and other BR receptors could act collectively to ensure stress memory via BIN2 → SnRK2s → ABF2, BES1 or BZR1–TPL –HDA19 repressor complexes and BZR1/BES1 → FLC/FCA pathway. The third mechanism is stress acclimation by the BR-mediated stabilization of endoplasmic proteins in the ERAD process. New research prospects involving the BR signaling pathway in relation to stress adaptation are very intriguing and include the study of BR and ABA interaction pathways, chromatin modifications, and the ERAD process.

**Author Contributions:** Conception, data analysis, manuscript writing, V.P.B.; analysis and interpretation of data, revising for important intellectual content, final approval, T.V.A. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by the Russian Science Foundation, grant number 18-44-08001 (VPB).

**Conflicts of Interest:** The authors declare no conflict of interest.


**4.5. Polynomial solvers**

The characteristic equation for an *n*th order system is an *n*th order polynomial. As discussed above, the Cayley–Hamilton theorem will produce *n*-independent equations. For both partially described and fully described systems, a system of *n*th order polynomials will need to be solved for the unknown quantities. This will require a good polynomial solver or polynomial root-finding algorithm. For the problems presented in the rest of this chapter, the symbolic computer algebra software *Maple* by Maplesoft, Waterloo, Canada, was used to solve the problems although any modern numerical or symbolic software package could similarly be employed. For our simulations, the *Maple* built-in function *fsolve* was used, as well as the freely available package *DirectSearch*. The details of the *DirectSearch* package can be found in the study of Moiseev [17]. It was observed that *DirectSearch* produced many more (valid) solutions than did *fsolve* (recall that a unique solution to most of these problems does not exist and thus multiple solutions are expected). The existence of multiple solutions is desirable from an engineering design point of view in that it implies that there are many solutions possible and it is up to the designer to choose the most physically realisable one, within the problem constraints. For the Cayley–Hamilton (and determinant method presented in the rest of the chapter) to be effective, a good polynomial solver is required so that the multiple possible solutions can indeed be found.