CHEMISTRY

Polyacrylonitrile (PAN) nanofibers were prepared by an electrospinning technique. PAN nanofibers were chemically modified with amidoxime groups. The titanium oxide (TiO 2) was then introduced to amidoxime-modified PAN (OM-PAN), which was then used for the photodegradation of methylene blue in aqueous solution. The morphology and photodegradation study was investigated by using scanning electron microscopy (SEM) and UV-visible spectrophotometry, respectively. The SEM study showed the presence of TiO 2 particles on the surface of OM-PAN nanofiber mat in agglomerated form and was confirmed by energy dispersive X-rays analysis. The photodegradation study of methylene blue showed that the dye degradation was increased as increased in the irradiation time. The effect of pH on degradation efficiency showed that with an increase in pH the degradation efficiency increases.

Functionalized multiwalled carbon nanotubes (F-MWCNTs)/Co-Ti oxide nanocomposites and neat Co-Ti oxide nanoparticles were synthesized by chemical reduction method. The scanning electron microscopy micrographs show that the bimetallic NPs in F-MWCNTs/Co-Ti are present in dispersed form while the neat Co-Ti nanoparticles were found in agglomerated form. The formation of nanocomposites and neat Co-Ti nanoparticles was also confirmed by energy-dispersive X-ray. Both types of nanocomposites were employed as photocatalyst for the photodegradation of Rhodamine B in aqueous medium under UV light irradiation. The photodegradation study was performed via UV-Vis spectrophotometer. The photodegradation results show that F-MWCNTs/Co-Ti oxide NPs degraded about 93.35% dye within 150 min irradiation time while the neat Co-Ti oxide NPs degraded about 91.76% dye within same irradiation time. The F-MWCNTs/Co-Ti can be easily removed and recycled due to its bulky composite nature as compared to neat Co-Ti oxide NPs. The effect of dye concentration, catalyst dosage, pH of medium and activity of recycled catalyst was also evaluated.

Titanium oxide supported palladium (TiO 2 /Pd) and titanium oxide supported platinum (TiO 2 /Pt) nanoparticles were prepared from their precursors through the incipient wetness method. The TiO 2 /Pd and TiO 2 /Pt nanoparticles were characterized by scanning electron microscopy (SEM), and energy dispersive X-rays (EDX), while the photodegradation study of methyl violet was performed by UV/VIS spectrophotometry. The morphological study shows that the Pd and Pt were well deposited on the surface of TiO 2 , which was confirmed by EDX. Both TiO 2 /Pd and TiO 2 /Pt nanoparticles were used as photocatalysts for the photodegradation of methyl violet in aqueous media under UV-light irradiation. The photodegradation study revealed that the TiO 2 /Pd and TiO 2 /Pt nanoparticles degraded about 95 and 78% of dye within 20 min, respectively. The effect of various parameters such as catalyst dosage, concentration of dye, and medium on the photocatalytic degradation was examined. The activity of recovered TiO 2 /Pd and TiO 2 /Pt nanoparticles was studied.

Graphene/cobalt-manganese oxides nanocomposites were prepared from their precursor through chemical reduction where NaOH was used as a reducing agent. The obtained GNs/Co-Mn nanocomposites were used as photocatalyst for the photodegradation of Neutral Red Chloride (NRC) dye in aqueous solution under sunlight as a function of time and catalyst dosage. The morphology and photodegradation study was carried out using scanning electron microscopy (SEM) and UV-VIS spectrophotometry, respectively. The SEM image showed the presence of Co-Mn nanoparticles on the surface of GNs, which were also confirmed by energy dispersive X-ray analysis. The photodegradation study of NRC showed that the degradation of dye increased with an increase in irradiation time, and 94% of dye was degraded within 5 min by GNs/Co-Mn. Photodegradation was also carried out with recovered catalyst, which degraded about 90% of dye within 5 min. The effect of catalyst dosage on the degradation of dye was also studied.

Functionalized multiwalled carbon nanotubes (F-MWCNTs)/Co–Ti oxide nanocomposites and neat Co–Ti oxide nanoparticles were synthesized by chemical reduction method. The scanning electron microscopy micrographs show that the bimetallic NPs in F-MWCNTs/Co–Ti are present in dispersed form while the neat Co–Ti nanoparticles were found in agglomerated form. The formation of nanocomposites and neat Co–Ti nanoparticles was also confirmed by energy-dispersive X-ray. Both types of nanocomposites were employed as photocatalyst for the photodegradation of Rhodamine B in aqueous medium under UV light irradiation. The photodegradation study was performed via UV–Vis spectrophotometer. The photodegradation results show that F-MWCNTs/Co–Ti oxide NPs degraded about 93.35% dye within 150 min irradiation time while the neat Co–Ti oxide NPs degraded about 91.76% dye within same irradiation time. The F-MWCNTs/Co–Ti can be easily removed and recycled due to its bulky composite nature as compared to neat C...

Abstract. The green synthesis of gold nanoparticles (Au NPs) from their precursor was carried out using Delphinium uncinatum and Erythrophyleum guineense plants extracts. The Au NPs obtained were characterized by various instrumental techniques such as scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and UV/Visible (UV/VIS) spectrophotometer. The SEM study presented that E. guineense (GE) and D. uncinatum (GN) synthesized gold nanoparticles was below 100 and 300 nm, respectively.  The micrographs also presented that E. guineense (GE) synthesized gold particles had irregular round shaped while the D. uncinatum (GN) synthesized nanoparticles had cylindrical shaped. The XRD spectra presented peaks at about 38.1°, 44.43°, 64.6° and 77.64° can be indexed to (111), (200), (220) and (311) orientation, respectively, which confirmed the presence of gold nanoparticles. It means that both E. guineense (GE) and D. uncinatum (GN) synthesized gold nanopar...

A specific finger-projected fixed-bed reactor (FPFBR) was designed to efficiently utilize magnetic nanoparticles (MnFe2O4/Bi-MnFe2O4) for a model reaction (hydrogenation of a greenhouse gas, CO2, to valuable products: VPs). Coprecipitation method, with desired modification was used for the preparation of magnetic nanoparticles (MNPs) with controlled shape and size. Eighteen fingers in a single chamber were designed in the fixed-bed reactor’s skeleton; each finger worked as an independent reaction core. Controlled flow of hydrogen and CO2 was continuously provided to preheated reaction cores (catalyst beds) from saturator. One of the major products methanol {(%: Conv, 22/Sel 61)} among VPs was identified and quantified by GC. The efficiency of self-designed reactor was 74% for the direct catalytic hydrogenation of CO2 to valuable organic products.

The unavailability of clean drinking water is one of the significant health issues in modern times. Industrial dyes are one of the dominant chemicals that make water unfit for drinking. Among these dyes, methylene blue (MB) is toxic, carcinogenic, and non-biodegradable and can cause a severe threat to human health and environmental safety. It is usually released in natural water sources, which becomes a health threat to human beings and living organisms. Hence, there is a need to develop an environmentally friendly, efficient technology for removing MB from wastewater. Photodegradation is an advanced oxidation process widely used for MB removal. It has the advantages of complete mineralization of dye into simple and nontoxic species with the potential to decrease the processing cost. This review provides a tutorial basis for the readers working in the dye degradation research area. We not only covered the basic principles of the process but also provided a wide range of previously p...

Photodegradation is the chemical conversion of large, toxic, and complex molecules into non-toxic, simpler, and lower molecular weight species due to light exposure. Heterogeneous photocatalysis has sufficient potential to degrade toxic organic pollutants present in wastewater. As industries discharge their effluents containing organic pollutants into natural water bodies, which penetrate into the subsurface through connected pores it is necessary to study this process in natural or tap water. Tap water (TW) is mainly obtained from underground wells having inorganic salts in a minute quantity with a conductivity of 500 μS/cm. TW contains inorganic anions, which affect the photocatalytic activity and photocatalysis process. The aim of this review is to evaluate the effect of TW on the photo-degradation of organic pollutants such as dyes, pharmaceutical products, pesticides, etc., with the support of the literature. The TW had a diverse effect on the photodegradation of organic pollut...

Background Photodegradation of organic pollutants is considered to be the most suitable and cheaper technique to counter the decontamination issues. Metal nanoparticles are considered to be the most effective heterogeneous photocatalysts for photodegradation of organic pollutants. Besides, iron oxide nanoparticles are well-known photocatalysts for degrading organic pollutants. Methods We reported the synthesis of neat iron oxide nanoparticles (Fe 3 O 4 NPs) and zirconia supported iron oxide nanoparticles (Fe 3 O 4 /ZrO 2 NPs) by facile chemical reduction technique for photodegradation ofa toxic azo dye namely methyl red. Results The XRD and FTIR analysis has demonstrated a crystalline phase Fe 3 O 4 NPs. The morphological features via scanning electronic microscopy (FESEM) suggested agglomerated morphology of neat Fe 3 O 4 NPs with 803.54 ± 5.11 nm average particle size and revealed the uniform morphology and homogenous dispersion of Fe 3 O 4 NPs over ZrO 2 surface in Fe 3 O 4 /ZrO 2 nanocomposite. A polydispersity index (PDI) of 0.47 showed sufficient variations in the particle size of neat Fe 3 O 4 NPs, which is also supported by the results obtained from atomic force microscopy (AFM), FESEM and Transmission Electron Microscopy (TEM). Fe 3 O 4 /ZrO 2 NPs demonstrated efficient methyl red degradation over a short period of time under simulated light and degraded about~91.0 ± 1.0% and 87.0 ± 1.0% dye in 40 min, under UV and visible light, respectively. Conclusion The excellent photodegradation efficacy and sustainability of Fe 3 O 4 /ZrO 2 NPs can be attributed to the homogenous distribution of Fe 3 O 4 NPs over ZrO 2 , which facilitates the generation of photoexcitons (electrons and holes), enhanced charge transfer and minimize the charge recombination.

Green synthesis has been introduced as an alternative to chemical synthesis due to the serious consequences. Metal nanoparticles synthesized through green approach have different pharmaceutical, medical and agricultural applications. The present study followed a green and simple route for the preparation of potentially bioactive gold nanoparticles (Au NPs). Au NPs were prepared via green synthesis approach using crude basic alkaloidal portion of the tuber of Delphinium chitralense. The green synthesized Au NPs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) fourier transform infrared (FTIR), and UV-Visible spectrophotometer. Morphological analysis shows that Au NPs have cubic geometry with different sizes. UV-Vis spectroscopic analysis confirmed the synthesis of Au NPs while XRD proved their pure crystalline phase. The Au NPs showed promising dose dependent inhibition of both AChE and BChE as compared to the c...

Removal of heavy metals and dyes from wastewater has received great attention due to scarcity of clean water worldwide. Herein an approach was introduced to attain this goal by employing a single material. Chitosan films were prepared, cross-linked it and utilized for the adsorption of cobalt from aqueous medium. The cobalt adsorbed chitosan was then reutilized as a photocatalyst for the photodegradation of methyl violet dyes. The prepared chitosan, cross-linked chitosan and cobalt adsorbed cross-linked chitosan were characterized through scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR). SEM and EDX confirmed the adsorption of cobalt on the cross-linked chitosan. TGA analysis proved the increase in thermal stability with cross-linking while FTIR confirmed the cross-linking of chitosan. Maximum cobalt adsorption of 144 mg/g occurs at 600 ppm salt concentration. The photodegradation s...

The Nickel oxide nanoparticles (NiO NPs) and Nickel oxide/Nanoclay nanocomposite (NiO/Nc NC) were synthesized by chemical reduction method and used for the photodegradation of Orange II dyes in aqueous solution. The synthesized samples were characterized through SEM, EDX, FTIR and TGA. The SEM analysis presented that the NiO NPs are spherical with irregular shapes and sizes. The size of particles is in the range of 100–400 nm. It was also observed that the NiO NPs are deposited on the surface of Nanoclay. The EDX study confirmed the formation of metal NPs and verify and purity. The FT-IR spectra of NiO and NiO/Nc NC presented peaks at 432 cm−1 and 504 cm−1, which correspond to NiO while peak at 1090–940 cm−1 is due to Si–O stretching vibration of orthosilicate anions and Si–O–Al groups. The photodegradation study illustrated that the NiO NPs and NiO/Nc NC degraded about 93 and 96% Orange II in aqueous medium, respectively within 20 min. The effect of various parameters like initial ...

The conventional chemical methods of nanoparticles synthesis have been effectively replaced by nanoparticle synthesis mediated by plants. The current study describes the environmental friendly synthesis of chromium oxide nanoparticles (Cr2O3 NPs) using Erythrophleum guineense plant extract. The synthesis of Cr2O3 NPs was validated by UV/VIS spectroscopy, Energy Dispersive X-Ray (EDX), Scanning Electron Microscopy (SEM), and X-ray diffraction (XRD) studies. The appearance of the Sharpe peak at 460 nm in the UV/Vis spectrum and the colour change caused by surface plasma resonance confirmed the formation of Cr2O3 NPs. The EDX spectrum of Cr2O3 nanoparticles revealed the presence of carbon, oxygen, and chromium, while SEM analysis revealed an irregular round morphology (with a size below 400 nm). In addition, XRD studies suggested their crystalline nature by the characteristic peaks at 34° and 36° and 42° (2Ɵ), respectively. The green synthesized Cr2O3 NPs showed promise as in-vitro cho...

The synergistic effect of binary CdTiO2 and ternary NiCdTiO2 on the photocatalytic efficiency of TiO2 nanoparticles was investigated. The SEM analysis demonstrates spherical TiO2 NPs of different sizes present in agglomerated form. The structural analysis of the nanocomposites reveals a porous structure for TiO2 with well deposited Cd and Ni NPs. TEM images show NiCdTiO2 nanocomposites as highly crystalline particles having spherical and cubical geometry with an average particle size of 20 nm. The EDX and XRD analysis confirm the purity and anatase phase of TiO2, respectively. Physical features of NiCdTiO2 nanocomposite were determined via BET analysis which shows that the surface area, pore size and pore volume are 61.2 m2/g, 10.6 nm and 0.1 cm3/g, respectively. The absorbance wavelengths of the CdTiO2 and NiCdTiO2 nanocomposites have shown red shift as compared to the neat TiO2 due to coupling with Ni and Cd that results in the enhanced photocatalytic activity. The photocatalytic ...

This study was designed to estimate the relationship of peer victimization, psychological distress and self-esteem among teenagers. The sample consisted of 233 teenager's age range from 11 to 20 years. Data was collected from Kot Addu and Multan District. Convenient Sampling method was used to collect the data. Illinois Bully scale developed by (Espelage, D. L. & Holt, 2001) consisted of 18 items was used to check the rate of Peer Victimization. A 20 item state Self Esteem scale developed by (Heatherton, T. F. & Polivy, 1991) was taken to check the level of self-esteem among teenagers. Another 10 item Kessler psychological Distress scale (K10) developed by (Kessler & Mroczek, 1992) was used to check the level of distress among teenagers. The results were analyzed through SPSS. The findings of the study show that peer victimization leads to psychological distress and victimized teenagers have low level of self-esteem. It was also found that rate of peer victimization is high among school going teenagers as compared to college or university. Result further exposed that there is no significance difference in peer victimization on the basis of demographic variables like age group, gender, parent's qualification, no of siblings and family system.

This study was designed to estimate the relationship of peer victimization, psychological distress and self-esteem among teenagers. The sample consisted of 233 teenager’s age range from 11 to 20 years. Data was collected from Kot Addu and Multan District. Convenient Sampling method was used to collect the data. Illinois Bully scale developed by (Espelage, D. L. & Holt, 2001) consisted of 18 items was used to check the rate of Peer Victimization. A 20 item state Self Esteem scale developed by (Heatherton, T. F.…

In this article, an efficient numerical approach for the solution of second-order delay differential equations to deal with the experimentation of the Internet of Industrial Things (IIoT) is presented. With the help of the Haar wavelet technique, the considered problem is transformed into a system of algebraic equations which is then solved for the required results by using Gauss elimination algorithm. Some numerical examples for convergence of the proposed technique are taken from the literature. Maximum absolute and root mean square errors are calculated for various collocation points. The results show that the Haar wavelet method is an effective method for solving delay differential equations of second order. The convergence rate is also measured for various collocation points, which is almost equal to 2.

The title compound, C 15 H 14 O 5 , is a natural product, isolated from Sorbus lanata Syn. Pyrus lanata (D. Don) found in Pakistan. The compound is composed of three spiro-fused rings. The dihedral angle between the mean planes of the benzene rings is 4.81 (13). The methoxy groups are oriented at dihedral angles of 74.44 (14), 83.0 (2) and 66.3 (2) with respect to the planes of the benzene rings to which they are attached. The molecule is consolidated by three intramolecular O-HÁ Á ÁO and C-HÁ Á ÁO hydrogen bonds. In the crystal, molecules are linked by intermolecular O-HÁ Á ÁO hydrogen bonds, forming infinite chains along the b axis.