**6.1 Plant species**

*Assessment and Management of Radioactive and Electronic Wastes*

destruction etc.

heating, etc.

Over the previous years, several methods have been used to deal with the radioactive waste from contaminated sites. Though, these methods are costly and inefficient in their concert. The chemical methods generate large volumes of sludge and increase the cost of maintenance. Thermal methods are technically difficult and adversely affect the valuable component of soil by degrading it [21]. Two major procedures that are conventionally used to remediate the radioactive contaminated sites are: [22].

1.*Ex-situ methods***:** This method requires the removal of contaminated soil for treatment on/off site and then returning the treated soil to the site. The example of ex-situ methods are; soil leaching, solidification, immobilization, vitrification, heap leaching, ground disposal, sea disposal, incineration, and or

2.*In-situ methods***:** In this method excavation of contaminated location is not needed. The examples are; de-chlorination, bottom sealing, electromagnetic

Phytoremediation is a novel resolution that effectively and inexpensively extracts out the contaminants from the site and scrubs up the wasteland [23]. Phytoremediation makes use of green plants to clean up and treat radioactive contaminated sites for example soil, water and sediments. Plants have notable features that help them absorb contaminants into their systems with their endorsement capabilities such as translocation, bioaccumulation and contaminant degradation. Many plant species have been successful in efficiently accumulating the radionuclides in their stems and leaves and hence remediating the contaminated site [21]. This chapter evaluates some of the research that has been done on phytoremediation of radioactive metals and aims to discuss the potential of phytoremediation, highlight the general mechanisms of plant uptake, give a brief overview on radioactive metals (especially: Uranium-238, Thorium-232, Radium-226) uptake by plants,

and report the advantages and limitations associated with this method.

organs of the plant—leaves, stems and roots [24, 25].

1.**Phytoextraction:** Plants degrading pollutants from the soil (tailings) and

2.**Phytodegradation:** Plants removing pollutants by using hydrolytic enzymes and metabolites in plants; however, this method may be limited only to degra-

3.**Phytostabilization:** Plants reducing mobility and bioavailability of pollutants in the soil either by immobilization and precipitation, or by preventing

4.**Phytovolatilization:** Volatilization of pollutants into the air directly or indirectly via plant uptake into tissues and organs, and then transformation of the

5.**Rhizofiltration:** Plant roots strongly absorbing, accumulating and/or precipitating contaminants from aqueous waste streams or soil water almost exclu-

concentrating the contaminants in the harvestable portions of plants; i.e., in all

**5. Six main subgroups in phytoremediation**

dation of organic contaminants [26, 27].

products into volatile compounds [25, 30].

contaminant migration [28, 29].

sively into the root system [31, 32].

**34**

Plant species with superior remediation ability of the concerned radioactive waste are screened and carefully chosen. The success of phytoremediation technique depends upon the ability of the plant to accumulate [36].


Hybrid Aggregates

**Chapter 5**

Concrete

*Jianhui Yang*

Code requirements.

shale pottery

concrete?

**81**

**1. Introduction**

concrete have this effect too?

under complicated stress and in reinforced concrete?

**Abstract**

The Influence of Hybrid

Aggregates on Different Types of

This chapter presents different experimental results regarding the influences of normal-weight sand and lightweight sand (shale pottery (SP)) on different types of concrete. Because of the porosity of lightweight aggregates (LWAs), which can absorb and release water in concrete, the effect of concrete curing is better, and thus the properties of concrete are improved. On the other hand, because the lightweight coarse aggregate (LWCA) rises easily in all-lightweight concrete (ALWC) during pumping and vibration and the cost of ALWC is also higher, a method of replacing part of the lightweight aggregates in ALWC with normalweight aggregates is used. These new types of concretes include sand lightweight concrete (SLWC), gravel lightweight concrete (GLWC), hybrid aggregate lightweight concrete (HALWC), and so on. This chapter mainly discusses the properties of lightweight aggregate concrete (LWAC), lightweight sand foamed concrete, lightweight sand mortar, and reinforced LWAC. The chapter also includes LWAC of high temperature, low temperature, durability, and uni- and multiaxial mechanical properties according to the results of our research group over recent decades. All of the experimental results show that the properties can meet Chinese National

**Keywords:** lightweight aggregate concrete, foamed concrete, mortar, reinforced concrete beam, durability, high temperature, low temperature, shale ceramsite,

There are notable differences between lightweight aggregates and normalweight aggregates (NWA), so what are the different effects on different types of

Lightweight coarse aggregate has a softening effect; does lightweight aggregate

Can the lightweight concrete be used under special environmental conditions such as negative temperature, elevated temperature, and chemical corrosion? Are there any changes in the mechanical performance of lightweight concrete

Since 2005, it has been prohibited to mine river sand in most areas of China. The relevant laws, such as the *Water Law of the People's Republic of China* (2002, 2016),


**1. Introduction**

Computational Intelligence in Electromyography Analysis – 220 A Perspective on Current Applications and Future Challenges

Vol.20, No.1, pp. 89-101, ISSN 1050-6411

Zhang, Z. G.; Liu, H. T.; Chan, S. C.; Luk, K. D. & Hu, Y. (2010). Time-dependent Power Spectral Density Estimation of Surface Electromyograhy during Isometric Muscle Contraction : Methods and Comparisons. *Journal of Electromyography and Kinesiology*,


**3. Results and discussion**

### **3.1 Electropolymerization kinetics and mechanisms of of OCP and OHP 3.1.1 Electropolymerization**

Electropolymerization of OCP or OHP on platinum electrode from aqueous solution containing 0.6M H2SO4 at 303 K in the absence and presence of monomer, was studied by cyclic voltammetry at potential between -366 and +1780 mV(vs. SCE) with scan rate of 25 mVs-1.

The obtained voltammograms in absence and presence of monomer is represented in Fig. 1(a-c). The voltammogram in the absence of monomer exhibit an oxidation peak (I) which developed at -300 mV vs. SCE, which is a result of hydrogen adsorption on Pt electrode [Arslan et al, 2005]. While, the voltammograms in the presence of OCP exhibit two oxidation peaks (I and II) that progressively developed at -300 and +863 mV (vs. SCE) repetitively and one reduction peak (II') at +248 mV (vs. SCE). While in the presence of OHP ; two oxidation peaks (I and II) that progressively developed at --200 and +622 mV (vs. SCE) repetitively and one reduction peak (II') at +0.20 mV (vs. SCE). One one hand, the first oxidation peaks (I) are a result of hydrogen reduction [Arslan et al, 2005] as mentioned above where, the second oxidation peaks (II) correspond to oxidation of monomer to give phenoxy radical which adsorbed on Pt-electrode [Gattrell & Kirk,1993]. The adsorbed radicals react with

Note: peak (I) in both (b) and (c) is not shown in the figure.

Fig. 3. Cyclic voltammograms of solutions containing 0.06M H2SO4 at 303 K with scan rate 25mVs-1.

Electropolymerization of OCP or OHP on platinum electrode from aqueous solution containing 0.6M H2SO4 at 303 K in the absence and presence of monomer, was studied by cyclic voltammetry at potential between -366 and +1780 mV(vs. SCE) with scan rate of 25

The obtained voltammograms in absence and presence of monomer is represented in Fig. 1(a-c). The voltammogram in the absence of monomer exhibit an oxidation peak (I) which developed at -300 mV vs. SCE, which is a result of hydrogen adsorption on Pt electrode [Arslan et al, 2005]. While, the voltammograms in the presence of OCP exhibit two oxidation peaks (I and II) that progressively developed at -300 and +863 mV (vs. SCE) repetitively and one reduction peak (II') at +248 mV (vs. SCE). While in the presence of OHP ; two oxidation peaks (I and II) that progressively developed at --200 and +622 mV (vs. SCE) repetitively and one reduction peak (II') at +0.20 mV (vs. SCE). One one hand, the first oxidation peaks (I) are a result of hydrogen reduction [Arslan et al, 2005] as mentioned above where, the second oxidation peaks (II) correspond to oxidation of monomer to give phenoxy radical which adsorbed on Pt-electrode [Gattrell & Kirk,1993]. The adsorbed radicals react with

**3.1 Electropolymerization kinetics and mechanisms of of OCP and OHP**

**3. Results and discussion**

**3.1.1 Electropolymerization**

Note: peak (I) in both (b) and (c) is not shown in the figure.

25mVs-1.

Fig. 3. Cyclic voltammograms of solutions containing 0.06M H2SO4 at 303 K with scan rate

mVs-1.

other monomer molecule via head-to-tail coupling to form predominantly a para-linked dimeric radical and so on to form oligomer and polymer film; this film is a chain of isolated aromatic rings (polyethers) without π-electrons delocalization between each unit as shown in schemes (1 and 2). The oxidation occurs at more positive values ~ + 863 and +622 mV vs. SEC where the presence of (Cl and OH) make the oxidation process difficult.

On reversing the potential scan from, the reversing anodic current is very small indicating the presence of polymer layer adhered to the Pt-surface [Sayyah et al, 2010]. One cathodic peak (II') was found which could be ascribed to the reduction of the formed polymer films.

The effects of repetitive cycling on Pt- electrode in aqueous solution containing 0.6M H2SO4 with and without monomer at 303 K are shown in Fig. 4 (a-c). The data reveal that, in absence of monomer, the repetitive cycling show the oxidation peak (I) only. The current of this peak (ipI) is almost the same and not affected with cycling up to 6 cycles (c.f. fig. 4 (a)).

Fig. 4. Repetitive cycling of electropolymerization from solution containing 0.6M H2SO4 at 303 K with scan rate 25 mVs-1

Electropolymerization of Some Ortho-Substituted Phenol Derivatives on Pt-Electrode from

H2SO4 at 303 K with scan rate from 15 to 45 mV s-1) are shown in Table 1;

Scan rate, (Vs-1)

Table 1. Calculated values of Diffusion coefficients.

*For OCP; ipII (mA) = 0.207 v1/2 (mV s-1)1/2 – 0.60 : r2*=*0.90 and, For OHP; ipII (mA) = 0.228 v1/2 (mV s-1)1/2 – 0.53: r2*=*0.99*

Fig. 6. Relation between ipII and square root of scan rate

These linear regression equations are;

Aqueous Acidic Solution; Kinetics, Mechanism, Electrochemical Studies and Characterization of… 29

 ipII = 0.4463 n F A C ( n F *v* D / R T )1/2 (4) where n is the number of exchanged electron in the mechanism, F is Faraday's constant (96485 Cmol-1), A is the electrode area (cm2), C is the bulk concentration, D is the analyst diffusing coefficient (cm2s-1), and v is the scan rate (Vs-1). R is the universal gas constant (8.134 Jmol-1K-1), T is the absolute temperature (K).The calculated values of D (at 0.6 M

Diffusing coefficient, (m2s-1)

The values of D are seen to be constant for both cases over the range of sweep rates, which

Figure 6 (a and b) shows the linear dependence of the anodic current peak, (ipII) versus ν1/2.

From Fig. 6 and the above equations we notice that; 0.9 < correlation coefficient (r2) <1. So we suggest that the electroformation of both POCP and POHP may be described partially by a diffusion-controlled process (diffusion of reacting species to the polymer film/solution interface). [Ardakani et al, 2009] It seems that, initially the electroformation of radical cations

0.015 1.83676 x 10-11 4.41282 x 10-11 0.020 2.15245 x 10-11 8.26886 x 10-11 0.025 7.16612 x 10-11 1.09351 x 10-10 0.030 9.11262 x 10-11 1.15739 x 10-10 0.045 1.07765 x 10-10 1.59405 x 10-10

again shows that the oxidation process is diffusion-controlled [sayyah et al, 2010].

OCP→POCP OHP→POHP

This means that, surface area of electrode is not affected by the H2 adsorption where, in presence of monomers (OCP or OHP) the data reveal that, during the second cycle both the oxidation and the reduction peak currents decrease significantly with repetitive cycling. This behavior is observed elsewhere as a result of fouling of electrode [Arslan et al, 2005] where phenolic products block the electrode surface and the formed film hinders diffusion of further phenoxide ions to the electrode surface, thereby causing a significant decrease in the anodic peak current and also decrease the cathodic peak current. The potential position of the redox peaks does not shift with increasing number of cycles, indicating that the oxidation and the reduction reactions are independent on the polymer thickness [Sayyah et al, 2010].

Figure 5 (a and b) illustrates the influence of the scan rate (15 – 45 mV s-1) on the potentiodynamic anodic polarization curves for OCP and OHP from aqueous solution containing 0.6 M H2SO4 at 303 K on platinum electrode. It is obvious that both the anodic and cathodic peak current densities (*ipII* and *ipII')* in the two cases increases with the increasing of the scan rate. This behavior may be explained as follows, when an enough potential is applied at Pt- surface causing oxidation of species in solution, a current arises due to the depletion of the species in the vicinity of the Pt- surface. As a consequence, a concentration gradient appears in the solution. The current (ip) is proportional to the gradient slope, dc/dx, imposed (i = dc/dx). As the scan rate increase the gradient increase and consequently the current (ip).

Fig. 5. Effect of Scan rate on electropolymerization on Pt electrode from solution containing 0.6M H2SO4 at 303 K.

Figure 6 (a and b) shows the linear dependency of the anodic peak current densities ( *ipII* ) which is corresponding to the formation of the polymer films POCP and POHP repetitivelyversus the square root of scan rate (*v*1/2). This linear relation suggests that the oxidation of OCP to POCP and/or OHP to POHP may be described by a partially diffusion-controlled process (diffusion of reacting species to the polymer film / solution interface) where the correlation coefficients (r2) is higher than 0.9 but not equal to 1.0 suggesting the non-ideal simulation relation (i.e: the process is not completely diffusion control but it is exactly a partially diffusion control. Values of *i*p are proportional directly to *v*1/2 according to Randless [Randless, 1984] and Sevick [Sevick, 1948] equation:

$$\mathbf{i\_{pll}} = 0.4463 \,\text{n} \,\text{F} \,\text{A} \,\text{C} \,\text{(n} \,\text{F} \,\text{v} \,\text{D} \,/\text{R} \,\text{T} \,\text{)}^{1/2} \tag{4}$$

where n is the number of exchanged electron in the mechanism, F is Faraday's constant (96485 Cmol-1), A is the electrode area (cm2), C is the bulk concentration, D is the analyst diffusing coefficient (cm2s-1), and v is the scan rate (Vs-1). R is the universal gas constant (8.134 Jmol-1K-1), T is the absolute temperature (K).The calculated values of D (at 0.6 M H2SO4 at 303 K with scan rate from 15 to 45 mV s-1) are shown in Table 1;

Table 1. Calculated values of Diffusion coefficients.

28 Electropolymerization

This means that, surface area of electrode is not affected by the H2 adsorption where, in presence of monomers (OCP or OHP) the data reveal that, during the second cycle both the oxidation and the reduction peak currents decrease significantly with repetitive cycling. This behavior is observed elsewhere as a result of fouling of electrode [Arslan et al, 2005] where phenolic products block the electrode surface and the formed film hinders diffusion of further phenoxide ions to the electrode surface, thereby causing a significant decrease in the anodic peak current and also decrease the cathodic peak current. The potential position of the redox peaks does not shift with increasing number of cycles, indicating that the oxidation and the

Figure 5 (a and b) illustrates the influence of the scan rate (15 – 45 mV s-1) on the potentiodynamic anodic polarization curves for OCP and OHP from aqueous solution containing 0.6 M H2SO4 at 303 K on platinum electrode. It is obvious that both the anodic and cathodic peak current densities (*ipII* and *ipII')* in the two cases increases with the increasing of the scan rate. This behavior may be explained as follows, when an enough potential is applied at Pt- surface causing oxidation of species in solution, a current arises due to the depletion of the species in the vicinity of the Pt- surface. As a consequence, a concentration gradient appears in the solution. The current (ip) is proportional to the gradient slope, dc/dx, imposed (i = dc/dx). As the scan rate increase the gradient increase

Fig. 5. Effect of Scan rate on electropolymerization on Pt electrode from solution containing

Figure 6 (a and b) shows the linear dependency of the anodic peak current densities ( *ipII* ) which is corresponding to the formation of the polymer films POCP and POHP repetitivelyversus the square root of scan rate (*v*1/2). This linear relation suggests that the oxidation of OCP to POCP and/or OHP to POHP may be described by a partially diffusion-controlled process (diffusion of reacting species to the polymer film / solution interface) where the correlation coefficients (r2) is higher than 0.9 but not equal to 1.0 suggesting the non-ideal simulation relation (i.e: the process is not completely diffusion control but it is exactly a partially diffusion control. Values of *i*p are proportional directly to *v*1/2 according to

Randless [Randless, 1984] and Sevick [Sevick, 1948] equation:

reduction reactions are independent on the polymer thickness [Sayyah et al, 2010].

and consequently the current (ip).

0.6M H2SO4 at 303 K.

The values of D are seen to be constant for both cases over the range of sweep rates, which again shows that the oxidation process is diffusion-controlled [sayyah et al, 2010].

Figure 6 (a and b) shows the linear dependence of the anodic current peak, (ipII) versus ν1/2. These linear regression equations are;

*For OCP; ipII (mA) = 0.207 v1/2 (mV s-1)1/2 – 0.60 : r2*=*0.90 and, For OHP; ipII (mA) = 0.228 v1/2 (mV s-1)1/2 – 0.53: r2*=*0.99*

From Fig. 6 and the above equations we notice that; 0.9 < correlation coefficient (r2) <1. So we suggest that the electroformation of both POCP and POHP may be described partially by a diffusion-controlled process (diffusion of reacting species to the polymer film/solution interface). [Ardakani et al, 2009] It seems that, initially the electroformation of radical cations

Fig. 6. Relation between ipII and square root of scan rate

Electropolymerization of Some Ortho-Substituted Phenol Derivatives on Pt-Electrode from

Fig. 7. Cyclic voltammetry curves showing the effect of monomers concentration on

electropolymerization and its related double logarithmic plot.

Aqueous Acidic Solution; Kinetics, Mechanism, Electrochemical Studies and Characterization of… 31

is controlled by charge transfer process. When the polymers become thick, the diffusion of reactant inside the film becomes the slowest step, the process changed to diffusion transfer, which confirms the data in Figure 4.

The intercepts in Figure 6 are small and negative, -0.60 and -0.53 for OCP and OHP respectively, which could be attributed to a decrease of the active area of the working electrode during the positive scan [Zanartu et al , 2002] or the increase of the covered area of working electrode by the adhered polymer sample, which confirm the data of Figure 4 .


*Article* **The Impact of COVID-19: The Phenomenological Effect of Burnout on Women in the Nonprofit Sector and Implications for the Post-Pandemic Work World**

**Patricia A. Clary \* and Patricia Vezina Rose**

Patricia Clary & Associates, Horseshoe Bend, AR 72512, USA **\*** Correspondence<EMAIL_ADDRESS>
**Abstract:** Research shows that 67% of the nonprofit sector workforce in the United States are women and worldwide, women account for the majority of employees in the nonprofit sector. Identified as service provider professionals, these women provide the care and nurture of countless people and yet often neglect themselves as they serve others out of passion or a strong work ethic. At the height of the COVID-19 pandemic, service provider professionals responded to an increased demand for programs and services with fewer resources. The increase in the demand for programs and services with a decrease in resources contributed to stress for these workers, leading to the phenomenon of burnout. To address the phenomenon of burnout, we propose that nonprofit organizations need to be systems thinking organizations and consider implications at the organization's micro, mezzo, and macro levels. Three themes emerged from this study, self-care at the micro level, psychological safety at the mezzo level, and reviewed and revised policies and procedures that address the unique needs of women at the macro level. The article considers the nonprofit sector, burnout, and women in the nonprofit sector and its implications for organizations at the micro, mezzo, and macro levels.

**Keywords:** nonprofit; burnout; self-care; well-being; systems-thinking; micro-level; mezzo-level; macro-level; COVID-19


**Author details**

Valeriu V. Jinescu1\*, Vali-Ifigenia Nicolof2 , George Jinescu3 and Simona-Eugenia Manea4

\*Address all correspondence to<EMAIL_ADDRESS>
1 Industrial Process Equipment Department, Politehnica University of Bucharest, Bucharest, Romania

2 Technical College "Carol I", Bucharest, Romania

3 Bucharest Emergency Hospital, Calea Floreasca, Bucharest, Romania

4 Horia Hulubei National Institute of Physics and Nuclear Engineering, Măgurele, Romania


**4. Enhancements to EAP-CRA**

or federation of RADIUS servers, the EAP-CRA system depends only on the existing infra‐ structure, hence, assuring simplicity. The use of existing CA-signed PKI certificates without necessitating other authentication mechanisms such as tokens or smart cards enables the EAP-CRA system to be confined. Further, EAP-CRA system is not limited to WLAN or WiMAX, it can be effectively used with any wireless network, harnessing the unique security features of that particular wireless network. Furthermore, the authentication mechanism (EAP-TLS, EAP-TTLS, EAP-PEAP etc.) used by the wireless network does not influence the EAP-CRA system because it does use any form of mappings between these protocols and the EAP-CRA protocol.

The above discussions illustrate the significance of the CRA approach and emphasize the need for a fast authentication mechanism as opposed to a hierarchical mechanism like the Edu-roam. Although Microsoft IAS provides a similar infrastructure to that of EAP-CRA, it is restricted to Microsoft EAP-PEAP authentications. In contrast EAP-CRA does not rely on any particular authentication protocol. It is designed to reap the maximum leverage of the authentication mechanism that is best for the particular home environment. Hence, when a hand-held device roams in a foreign network it will have the same security guarantee as in the home network. EAP-CRA is differentiated by other EAP methods in the aspects of communication scope by covering both the foreign and the home authentication servers. Other EAP methods such as EAP-TLS or EAP-TTLS do not consider server to server communication. EAP-CRA provides authentication and communication privacy between the foreign and the home authentication servers based on public key infrastructure. The home and foreign servers have got the public certificates of each other. EAP-CRA encrypts the authentication message twice and then sends it to the other foreign server ensuring privacy and authenticity of the message. Any message from home server will first be signed by the home server's private key and then by the foreign servers public key. Same process happens if the foreign server sends a message to the home

**Figure 7.** Comparison of Authentication Times

118 Selected Topics in WiMAX

The Enhanced CRA protocol provides authentication in two modes; Full Authentication and Re-Authentication. With regard to mutual authentication CRA uses RADIUS servers as suggested in IEEE 802.1x. CRA suggests direct communication between radius servers by prearranged agreement or the servers could find each other dynamically. In case the RADIUS servers do not have a pre-arranged agreement they can use their CA-signed PKI certificates to ascertain trust between servers.

All AAA servers that participate in the CRA must possess a CA-signed PKI certificate and be capable of obtaining the CA-signed PKI certificates of other participating AAA servers. Assuming that all AAA Servers that participate in the CRA are in possession of their CA-signed PKI certificates, the CRA protocol can communicate between the FOREIGN and the HOME AAA servers securely.


**Author details**

Alexis Rodriguez Carranza1 \*, Obidio Rubio Mercedes1 and Elder Joel Varas Peréz2

1 National University of Tujillo, Trujillo, Perú

2 National University Jorge Basadre-Tacna, Tacna, Perú

\*Address all correspondence to<EMAIL_ADDRESS>
© 2023 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


**Author details**

Syed Zaidi1 \*, Rahul Bollam1 and Kainat Saleem2

1 Department of General Internal Medicine, UPMC Mercy, Pittsburgh, United States of America

2 Department of General Internal Medicine, UPMC PUH/SHY, Pittsburgh, United States of America

\*Address all correspondence to<EMAIL_ADDRESS>
© 2021 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

*Electrolytes in the ICU DOI: http://dx.doi.org/10.5772/intechopen.96957*