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Preparation and modification of activated carbon for benzene adsorption by steam activation in the presence of KOH 被引量:12
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作者 Yao Xin Liu Jinchang +2 位作者 Gong Guozhuo Jiang Yu Xie Qiang 《International Journal of Mining Science and Technology》 SCIE EI 2013年第3期395-401,共7页
A series of activated carbons from Taixi anthracite were prepared by steam activation in the presence of KOH and then they were modified by different methods. The regulation of porosity and the modification of surface... A series of activated carbons from Taixi anthracite were prepared by steam activation in the presence of KOH and then they were modified by different methods. The regulation of porosity and the modification of surface chemistry were carried out with the aim to improve the benzene adsorption capacity of activated carbon. The influences of KOH and activation process parameters including activation temperature, activation time and steam flow rate on porosity of activated carbon were evaluated, and the effect of modification methods on surface chemistry was investigated. Also, the relationship between benzene adsorption capacity and porosity and surface chemistry was analyzed. Results show that activation temperature is the dominant factor in the activation process; the introduction of KOH into the raw material can enhance the reactivity of char in activation process, meanwhile it shows a negative effect on the porosity development, especially on the mesopore development. Results of FTIR analysis indicate that anthracite-based activated carbon with condensed aromatics and chemically inert oxygen does not present the nature to be surface modified. Besides, benzene adsorption capacity has an approximate linear relationship with surface area and in our preparation, benzene adsorption capacity and surface area of activated carbon are up to 1210 m 2 /g and 423 mg/g, respectively. 展开更多
关键词 activated carbon Steam activation Surface modification Benzene Potassium hydroxide
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Melamine Modification of Spherical Activated Carbon and Its Effects on Acetylene Hydrochlorination 被引量:2
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作者 韩伟杰 WANG Xugen +5 位作者 ZHU Mingyuan ZHANG Haiyang CHEN Kun WANG Qinqin LI Xiaoyan 代斌 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第6期1147-1151,共5页
Commercial spherical activated carbon(SAC) was modified by impregnation to enhance the catalytic properties of SAC in acetylene hydrochlorination through melamine modification. Different modification conditions for ... Commercial spherical activated carbon(SAC) was modified by impregnation to enhance the catalytic properties of SAC in acetylene hydrochlorination through melamine modification. Different modification conditions for SAC with nitrogen were compared by changing the SAC-Melamine ratios. The effect of carbonization temperature on the modification was also investigated. Surface chemistry and adsorption properties of the modified and unmodified SACs were studied by scanning electron microscope(SEM), X-ray photoelectron spectroscopy(XPS), elementary analysis, BET, and temperature-programmed desorption(TPD). Moreover, the catalytic properties of SAC in acetylene hydrochlorination under differently modified conditions were also investigated. Elemental analysis showed that the nitrogen content of the modified SAC was greatly improved. XPS revealed that nitrogen mainly exists in Pyrrole nitrogen and Pyridine nitrogen. TPD showed that desorption of C2H2 was changed by modification. The conversion rate of acetylene was up to 70% under the following reaction conditions: temperature, 150 ℃; C2H2 hourly space velocity(GHSV), 36 h-1; feed volume ratio V(HCl)/V(C2H2) = 1.15. The catalytic properties of SAC were improved significantly via melamine modification. 展开更多
关键词 spherical activated carbon melamine modification catalytic properties acetylene hydrochlorination
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Acid/Base Treatment of Monolithic Activated Carbon for Coating Silver with Tunable Morphology 被引量:1
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作者 程辞 WANG Fei +3 位作者 赵斌元 宁月生 LAI Yijian WANG Lei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第4期760-765,共6页
Silver coatings on the exterior surface of monolithic activated carbon(MAC) with different morphology were prepared by directly immersing MAC into [Ag(NH3)2]NO3 solution. Acid and base treatments were employed to ... Silver coatings on the exterior surface of monolithic activated carbon(MAC) with different morphology were prepared by directly immersing MAC into [Ag(NH3)2]NO3 solution. Acid and base treatments were employed to modify the surface oxygenic groups of MAC, respectively. The MACs' Brunauer-EmmettTeller(BET) surface area, surface groups, and silver coating morphology were characterized by N2 adsorption, elemental analysis(EA), X-ray photoelectron spectroscopy(XPS), and scanning electron microscopy(SEM), respectively. The coating morphology was found to be closely related to the surface area and surface functional groups of MAC. For a raw MAC which contained a variety of oxygenic groups, HNO3 treatment enhanced the relative amount of highly oxidized groups such as carboxyl and carbonates, which disfavored the deposition of silver particles. By contrast, Na OH treatment significantly improved the amount of carbonyl groups, which in turn improved the deposition amount of silver. Importantly, lamella silver was produced on raw MAC while Na OH treatment resulted in granular particles because of the capping effect of carbonyl groups. At appropriate [Ag(NH3)2]NO3 concentrations, silver nanoparticles smaller than 100 nm were homogeneously dispersed on Na OH-treated MAC. The successful tuning of the size and morphology of silver coatings on MAC is promising for novel applications in air purification and for antibacterial or aesthetic purposes. 展开更多
关键词 monolithic activated carbon silver coating morphology functional groups surface modification
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Photoactive area modification in bulk heterojunction organic solar cells using optimization of electrochemically synthesized ZnO nanorods
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作者 Mehdi Ahmadi Sajjad Rashidi Dafeh 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期422-427,共6页
In this work, ZnO nanorod arrays grown by an electrochemical deposition method are investigated. The crucial parameters of length, diameter, and density of the nanorods are optimized over the synthesize process and na... In this work, ZnO nanorod arrays grown by an electrochemical deposition method are investigated. The crucial parameters of length, diameter, and density of the nanorods are optimized over the synthesize process and nanorods growth time. Crystalline structure, morphologies, and optical properties of ZnO nanorod arrays are studied by different techniques such as x-ray diffraction, scanning electron microscope, atomic force microscope, and UV-visible transmission spectra. The ZnO nanorod arrays are employed in an inverted bulk heterojunction organic solar cell of Poly (3-hexylthiophene):[6- 6] Phenyl-(6) butyric acid methyl ester to introduce more surface contact between the electron transporter layer and the active layer. Our results show that the deposition time is a very important factor to achieve the aligned and uniform ZnO nanorods with suitable surface density which is required for effective infiltration of active area into the ZnO nanorod spacing and make a maximum interfacial surface contact for electron collection, as overgrowing causes nanorods to be too dense and thick and results in high resistance and lower visible light transmittance. By optimizing the thickness of the active layer on top of ZnO nanorods, an improved efficiency of 3.17% with a high FF beyond 60% was achieved. 展开更多
关键词 electrochemical deposition density-controlled ZnO nanorods inverted polymer solar cells active area modification
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Adsorption of Cu(Ⅱ) from Aqueous Solution Using Activated Carbon Modified with Nitric Acid
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作者 黄国林 SHI Jeffrey +1 位作者 杨婥 梁喜珍 《Journal of Donghua University(English Edition)》 EI CAS 2012年第4期363-369,共7页
The objective of the presented work was to assess the adsorption processes of Cu ( II ) from aqueous solution onto a granular activated carbon (GAC) and a modified activated carbon (MAC) with nitric acid. Availa... The objective of the presented work was to assess the adsorption processes of Cu ( II ) from aqueous solution onto a granular activated carbon (GAC) and a modified activated carbon (MAC) with nitric acid. Available surface functional groups, pH of the isoclectric point (pHIEP ), and Fourier transform infrared spectroscopes were obtained to characterize the GAC/MAC. Factors influencing Cu ( II ) adsorption such as adsorbent dosage, pH of solution, and contact time of the adsorption onto the MAC/GAC had been investigated in a batch experiment. Experimental equilibrium data had been obtained and modelled using both Frenndlich and Langmuir dassicai adsorption isotherms and the data fitted better to Langmulr isotherm. It was found that nitric acid modification increased the Cu( II ) adsorption capacity to 90.9 mg/ g, which was higher than the unmodified carbon by 41%. Two simplified models including pseudo-first-order and pseudo-second- order equations were selected to follow the adsorption processes. 展开更多
关键词 modification of activated carbon Cu II adsorption adsorption isotherm: adsorption kinetics
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A strategy to enhance the insecticidal potency of Vip3Aa by introducing additional cleavage sites to increase its proteolytic activation efficiency 被引量:1
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作者 Kun Jiang Zhe Chen +8 位作者 Yiting Shi Yuanrong Zang Chengbin Shang Xi Huang Jiahe Zang Zhudong Bai Xuyao Jiao Jun Cai Xiang Gao 《Engineering Microbiology》 2023年第4期3-10,共8页
Microbially derived,protein-based biopesticides have become a vital element in pest management strategies.Vip3 family proteins from Bacillus thuringiensis have distinct characteristics from known insecticidal Cry toxi... Microbially derived,protein-based biopesticides have become a vital element in pest management strategies.Vip3 family proteins from Bacillus thuringiensis have distinct characteristics from known insecticidal Cry toxins and show efficient insecticidal activity against several detrimental lepidopteran pests.They are considered to be a promising toxic candidate for the management of various detrimental pests.In this study,we found that in addition to the preliminary digestion sites lysine,there are multiple cleavage activation sites in the linker region between domain I(DI)and DII of Vip3Aa.We further demonstrated that by adding more cleavage sites between DI and DII of Vip3Aa,its proteolysis efficiency by midgut proteases can be significantly increased,and correspondingly enhance its insecticidal activity against Spodoptera frugiperda and Helicoverpa armigera larvae.Our study promotes the understanding of the insecticidal mechanism of Vip3 proteins and illustrates an eas-ily implementable strategy to increase the insecticidal potency of Vip3Aa.This facilitates their potential future development and efficient application for sustainable agriculture. 展开更多
关键词 Insecticidal protein Activation mechanism Insecticidal activity modification Insecticidal mechanism Bacillus thuringiensis
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Identification of the novel N-phenylbenzenesulfonamide derivatives as potent HIV inhibitors 被引量:2
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作者 Yong Sun Cui-Lin Lu +8 位作者 Chang-Yuan Wang Rui-Rui Wang Ke-Xin Liu Liu-Meng Yang Yu-Hong Zhen Hou-Li Zhang Chao Wang Yong-Tang Zheng Xiao-Dong Ma 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第2期243-247,共5页
Searching for more safe and effective agents for HIV treatments is still an urgent topic worldwide.Based on our continuous modifications on the benzophenone derivatives as HIV-1 reverse transcriptase(RT)inhibitors,a... Searching for more safe and effective agents for HIV treatments is still an urgent topic worldwide.Based on our continuous modifications on the benzophenone derivatives as HIV-1 reverse transcriptase(RT)inhibitors,a new template bearing N-phenylbenzenesulfonamide(PBSA) structure was designed to enhance the interactions with HIV-1 RT.In this manuscript,a series of PBSA derivatives were synthesized and evaluated for their anti-HIV-1 activity.The preliminary test showed that these compounds were potent to inhibit wild-type HIV-1 with EC_(50) values ranging of 0.105-14.531 μmol/L.In particular,compound 13 f not only has high anti-HIV-1 activity(0.108 μmol/L),but also possesses low toxicity with a Tl value of 1816.6.Furthermore,the major interactions of the inhibitor 13 f with HIV-1 RT were also investigated using the molecular modelling.Our discovered structure-activity relationships(SARs) of these analogues may serve as an important clue for further optimizations. 展开更多
关键词 Benzophenone N-Phenylbenzenesulfonamide Structure modification Anti-HIV activity
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Cerium based shells with palladium cores encapsulated:an efficient catalyst for carbon monoxide oxidation 被引量:1
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作者 汪淼 沈美庆 +3 位作者 王建强 魏光曦 李航 王军 《Journal of Rare Earths》 SCIE EI CAS CSCD 2014年第12期1114-1119,共6页
Pd@Zr/Ce O2 core-shell catalyst prepared by hydrothermal method was applied in CO oxidation reaction, exhibiting high CO oxidation activity at low temperature.XRD(X-ray diffraction) analysis demonstrated that the re... Pd@Zr/Ce O2 core-shell catalyst prepared by hydrothermal method was applied in CO oxidation reaction, exhibiting high CO oxidation activity at low temperature.XRD(X-ray diffraction) analysis demonstrated that the remarkable enhancement of catalytic performance was found to depend on the presence of more oxygen vacancies in the core-shell structure, which contributed higher content of and ready release of active oxygen species at low temperature, confirmed by H2-TPR(temperature programed reduction) results.Interestingly, introducing a small amount of zirconium(0.5 wt.%) exhibited a significant improvement of catalytic activity because the introduction of Zr further improved the amount of crystal defects and promoted the migration of oxygen species. 展开更多
关键词 Pd@CeO2 core-shell catalyst Zr modification low-temperature CO oxidation activity oxygen vacancies rare earths
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Synthesis and insecticidal evaluation of phytoalexin phenalenones derivatives
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作者 Ya-Nan Zhang Yi-An Feng +1 位作者 Zhong Li Xu-Sheng Shao 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第6期1228-1231,共4页
Phenalenone is a kind of defensive compound biosynthesized inside plants in response to the outside attack such as fungus and nematodes.A set of derivatives encompassing structural modifications on the privileged phen... Phenalenone is a kind of defensive compound biosynthesized inside plants in response to the outside attack such as fungus and nematodes.A set of derivatives encompassing structural modifications on the privileged phenalenone scaffold were synthesized through introduction of phenyl and hydroxy!substitutes at 9-positon and 2-position and assessed their insecticidal activities against armyworm(Mythimna separata Walker) and cowpea aphids[Aphis craccivora).No obvious insecticidal activities of the synthesized compounds were observed against armyworm.Some of the 9-phenyl and 2-hydroxy substituted phenalenone analogues showed potential activities against cowpea aphids with 33%-41%mortality at 500 mg/L. 展开更多
关键词 Phenalenones derivatives Insecticidal activities Structural modifications
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Inhibition of thrombin by functionalized C_(60)nanoparticles revealed via in vitro assays and in silico studies
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作者 Yanyan Liu Jianjie Fu +3 位作者 Wenxiao Pan Qiao Xue Xian Liu Aiqian Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第1期285-295,共11页
The studies on the human toxicity of nanoparticles(NPs) are far behind the rapid development of engineered functionalized NPs. Fullerene has been widely used as drug carrier skeleton due to its reported low risk. Ho... The studies on the human toxicity of nanoparticles(NPs) are far behind the rapid development of engineered functionalized NPs. Fullerene has been widely used as drug carrier skeleton due to its reported low risk. However, different from other kinds of NPs, fullerene-based NPs(C_(60) NPs) have been found to have an anticoagulation effect, although the potential target is still unknown. In the study, both experimental and computational methods were adopted to gain mechanistic insight into the modulation of thrombin activity by nine kinds of C_(60) NPs with diverse surface chemistry properties. In vitro enzyme activity assays showed that all tested surface-modified C_(60) NPs exhibited thrombin inhibition ability. Kinetic studies coupled with competitive testing using 3 known inhibitors indicated that six of the C_(60) NPs, of greater hydrophobicity and hydrogen bond(HB) donor acidity or acceptor basicity, acted as competitive inhibitors of thrombin by directly interacting with the active site of thrombin. A simple quantitative nanostructure-activity relationship model relating the surface substituent properties to the inhibition potential was then established for the six competitive inhibitors.Molecular docking analysis revealed that the intermolecular HB interactions were important for the specific binding of C_(60) NPs to the active site canyon, while the additional stability provided by the surface groups through van der Waals interaction also play a key role in the thrombin binding affinity of the NPs. Our results suggest that thrombin is a possible target of the surface-functionalized C_(60) NPs relevant to their anticoagulation effect. 展开更多
关键词 Thrombin C_(60) nanoparticle(NP) Surface modification Activity inhibition Quantitative nanostructure-activity relationship Molecular docking
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