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Effect of thrombin on blood brain barrier permeability and its mechanism 被引量:42
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作者 关景霞 孙圣刚 +2 位作者 曹学兵 陈志斌 童萼塘 《Chinese Medical Journal》 SCIE CAS CSCD 2004年第11期1677-1681,共5页
Background Previous studies have indicated that thrombi n (TM) may play a major role in brain edema after intracerebral hemorrhages (ICHs). However, the mechanism of TM-induced brain edema is poorly understood. In th... Background Previous studies have indicated that thrombi n (TM) may play a major role in brain edema after intracerebral hemorrhages (ICHs). However, the mechanism of TM-induced brain edema is poorly understood. In this study, we explored the effect of TM on the permeability of the blood brain barrier (BBB) and investigated its possible mechanism, aiming at providing a potential target for brain edema therapy after ICHs.Methods TM or TM + cathepsin G (CATG) was stereotaxically injected into the right caudate nucleus of Sprague-Dawley rats in vivo. BBB permeability was measured by Evans-Blue extravasation. Brain water content was determined by the dry-wet weight method. Brain microvascular endothelial cells were then cultured in vitro. After TM or TM+CATG was added to the endothelial cell medium, changes in the morphology of cells were dynamically observed by phase-contrast light microscopy, and the expression of matrix metalloproteinase-2 (MMP-2) protein was measured by immunohistochemical method.Results BBB permeability increased at 6 hours after a TM injection into the ipsilateral caudate nucleus (P<0.05), peaked between 24 hours (P<0.01) and 48 hours (P<0.05) after the injection, and then declined. Brain water content changed in parallel with the changes in BBB permeability. However, at all time points, BBB permeability and brain water content after a TM+CATG injection were not significantly different from the respective parameters in the control group (P>0.05). TM induced endothelial cell contraction in vitro in a time-dependent manner and enhanced the expression of MMP-2 protein. After incubation with TM+CATG, cell morphology and MMP-2 expression did not change significantly as compared to the control group (P>0.05).Conclusions Increased BBB permeability may be one of the mechanisms behind TM-induced cerebral edema. TM induces endothelial cell contraction and promotes MMP-2 expression by activating protease activated receptor-1 (PAR-1), possibly leading to the opening of the BBB. 展开更多
关键词 THROMBIN cerebral edema blood brai n barrier protease activated receptor-1 matrix metalloproteinase-2 cathepsin G
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Combined alkaline and ultrasonic pretreatment of sludge before aerobic digestion 被引量:41
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作者 MAHAR Rasool Bux 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第3期279-284,共6页
Alkaline and ultrasonic sludge disintegration can be used as the pretreatment of waste activated sludge (WAS) to promote the subsequent anaerobic or aerobic digestion. In this study, different combinations of these ... Alkaline and ultrasonic sludge disintegration can be used as the pretreatment of waste activated sludge (WAS) to promote the subsequent anaerobic or aerobic digestion. In this study, different combinations of these two methods were investigated. The evaluation was based on the quantity of soluble chemical oxygen demand (SCOD) in the pretreated sludge as well as the degradation of organic matter in the subsequent aerobic digestion. For WAS samples with combined pretreatment, the released COD levels were higher than those with ultrasonic or alkaline pretreatment alone. When combined with the ultrasonic treatment, NaOH treatment was more efficient than Ca(OH)2 for WAS solubilization. The COD levels released in various sequential options of combined NaOH and ultrasonic treatments were in the the following descending order: simultaneous treatment 〉 NaOH treatment followed by ultrasonic treatment 〉 ultrasonic treatment followed by NaOH treatment. For simultaneous treatment, low NaOH dosage (100 g/kg dry solid), short duration (30 min) of NaOH treatment, and low ultrasonic specific energy (7500 kJ/kg dry solid) were suitable for sludge disintegration. Using combined NaOH and ultrasonic pretreatment with optimal parameters, the degradation efficiency of organic matter was increased from 38.0% to 50.7%, which is much higher than that with ultrasonic (42.5%) or with NaOH pretreatment (43.5%) in the subsequent aerobic digestion at the same retention time. 展开更多
关键词 waste activated sludge (WAS) ultrasonic treatment alkaline treatment aerobic digestion
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Analysis of bacterial community structures in two sewage treatment plants with different sludge properties and treatment performance by nested PCR-DGGE method 被引量:39
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作者 LIU Xin-chun ZHANG Yu YANG Min WANG Zhen-yu LV Wen-zhou 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第1期60-66,共7页
The bacterial community structures in two sewage treatment plants with different processes and performance were investigated by denaturing gradient gel electrophoresis (DGGE) of nested polymerase chain reaction (ne... The bacterial community structures in two sewage treatment plants with different processes and performance were investigated by denaturing gradient gel electrophoresis (DGGE) of nested polymerase chain reaction (nested PCR) amplified 16S rRNA gene fragments with group-specific primers. Samples of raw sewage and treated effluents were amplified using the whole-cell PCR method, and the activated sludge samples were amplified using the extracted genomic DNA before the PCR products were loaded on the same DGGE gel for bacterial community analysis. Ammonia-oxidizing bacterial and actinomycetic community analysis were also carried out to investigate the relationship between specific population structures and system or sludge performance. The two plants demonstrated a similarity in bacterial community structures of raw sewage and activated sludge, but they had different effluent populations. Many dominant bacterial populations of raw sewage did not appear in the activated sludge samples, suggesting that the dominant bacterial populations in raw sewage might not play an important role during wastewater treatment. Although the two plants had different sludge properties in terms of settleability and foam forming ability, they demonstrated similar actinomycetic community structures. For activated sludge with bad settling performance, the treated water presented a similar DGGE pattern with that of activated sludge, indicating the nonselective washout of bacteria from the system. The plant with better ammonium removal efficiency showed higher ammonia-oxidizing bacteria species richness. Analysis of sequencing results showed that the major populations in raw sewage were uncultured bacterium, while in activated sludge the predominant populations were beta proteobacteria. 展开更多
关键词 activated sludge wastewater treatment SEWAGE community analysis PCR-DGGE
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Colorectal cancer lymph node staining by activated carbon nanoparticles suspension in vivo or methylene blue in vitro 被引量:41
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作者 Hong-Ke Cai Hai-Fei He Wei Tian Mei-Qi Zhou Yue Hu Yong-Chuan Deng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第42期6148-6154,共7页
AIM:To investigate whether activated carbon nanoparticles suspension(ACNS) or methylene blue(MB) can increase the detected number of lymph nodes in colorectal cancer.METHODS:Sixty-seven of 72 colorectal cancer patient... AIM:To investigate whether activated carbon nanoparticles suspension(ACNS) or methylene blue(MB) can increase the detected number of lymph nodes in colorectal cancer.METHODS:Sixty-seven of 72 colorectal cancer patients treated at our hospital fulfilled the inclusion criteria of the study which was conducted from December 2010 to February 2012.Seven patients refused to participate.Eventually,60 patients were included,and randomly assigned to three groups(20 in each group):ACNS group(group A),MB group(group B) and non-stained conventional surgical group(group C).In group A,patients received subserosal injection of 1 mL ACNS in a 4-quadrant region around the mass.In group B,the main artery of specimen was identified and isolated after the specimen was removed,and 2 mL MB was slowly injected into the isolated,stretched and fixed vessel.In group C,no ACNS and MB were injected.All the mesentery lymph nodes were isolated and removed systematically by visually inspecting and palpating the adipose tissue.RESULTS:No difference was observed among the three groups in age,gender,tumor location,tumor diameter,T-stage,degree of differentiation,postoperative complications and peritoneal drainage retention time.The total number of detected lymph nodes was 535,476 and 223 in the three groups,respectively.The mean number of detected lymph nodes per patient was significantly higher in group A than in group C(26.8 ± 8.4 vs 12.2 ± 3.2,P < 0.001).Similarly,there were significantly more lymph nodes detected in group B than in group C(23.8 ± 6.9 vs 12.2 ± 3.2,P < 0.001).However,there was no significant difference between group A and group B.There were 50,46 and 32 metastatic lymph nodes dissected in 13 patients of group A,10 patients of group B and 11 patients of group C,without significant differences among the three groups.Eleven of the 60 patients had insufficient number of detected lymph nodes(< 12).Only one patient with T 4a rectal cancer had 10 lymph nodes detected in group B,the other 10 patients were all from group C.Based on 展开更多
关键词 NANOTECHNOLOGY activated carbon nanoparticles suspension Methylene blue Lymph nodes Colorectal cancer
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Functions and behaviors of activated sludge extracellular polymeric substances (EPS): a promising environmental interest 被引量:37
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作者 TIAN Yu ZHENG Lei SUN De-zhi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第3期420-427,共8页
Extracellular polymeric substances (EPS) are the predominant constituents of activated sludge and represent up to 80% of the mass of activated sludge. They play a crucial role in the flocculation, settling and dewat... Extracellular polymeric substances (EPS) are the predominant constituents of activated sludge and represent up to 80% of the mass of activated sludge. They play a crucial role in the flocculation, settling and dewatering of activated sludge. Furthermore, EPS also show great efficiency in binding heavy metals. So EPS are key factors influencing reduction in sludge volume and mass, as well as activity and utilization of sludge. EPS are of considerable environmental interest and hundreds of articles on EPS have been published abroad, while information on EPS in China is limited. In this paper, results of over 60 publications related to constituents and characteristics of EPS and their influences on flocculation, settling and dewatering of sludge are compiled and analyzed. Metal-binding ability of EPS is also discussed, together with a brief consideration of possible research interests in the future. 展开更多
关键词 activated sludge environmental interest extracellular polymeric substances (EPS)
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Peanut Shell Activated Carbon: Characterization, Surface Modification and Adsorption of Pb^2+ from Aqueous Solution 被引量:36
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作者 徐涛 刘晓勤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第3期401-406,共6页
Metal ion contamination of drinking water and waste water, especially with heavy metal ion such as lead, is a serious and ongoing problem. In this work, activated carbon prepared from peanut shell (PAC) was used for... Metal ion contamination of drinking water and waste water, especially with heavy metal ion such as lead, is a serious and ongoing problem. In this work, activated carbon prepared from peanut shell (PAC) was used for the removal of Pb^2+ from aqueous solution. The impacts of the Pb25 adsorption capacities of the acid-modified carbons oxidized with HNO3 were also investigated. The surface functional groups of PAC were confirmed by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), Boehm titration. The textural properties (surface area, total pore volume) were evaluated from the nitrogen adsorption isotherm at 77 K. The experimental results presented indicated that the adsorption data fitted better with the Langmuir adsorption model. A comparative study with a commercial granular activated carbon (GAC) showed that PAC was 10.3 times more efficient compared to GAC based on Langmuir maximum adsorption capacity. Further analysis results by the Langmuir equation showed that HNO3 [20% (by mass)] modified PAC has larger adsorption capacity of Pb^2+ from aqueous solution (as much as 35.5 mg·g^-1). The adsorption capacity enhancement ascribed to pore widening, increased cation-exchange capacity by oxygen groups, and the promoted hydrophilicity of the carbon surface. 展开更多
关键词 activated carbon phosphoric acid ADSORPTION wastewater treatment surface modification
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Drinking water production by uitrafiltration of Songhuajiang River with PAC adsorption 被引量:31
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作者 XIA Sheng-ji LIU Ya-nane +1 位作者 LI Xing YAO Juan-juan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第5期536-539,共4页
In recent years, membrane ultrafiltration (UF) of surface water for drinking water treatment has become a more attractive technology worldwide as a possible alternative treatment to conventional clarification. To ev... In recent years, membrane ultrafiltration (UF) of surface water for drinking water treatment has become a more attractive technology worldwide as a possible alternative treatment to conventional clarification. To evaluate the performance of ultrafiltration membranes for treatment of surface water in North China, a 48-m^2 low pressure hollow fiber membrane ultrafiltration pilot plant was constructed. Ultrafiltration was operated in cross-flow and with powdered activated carbon (PAC) adsorption. Turbidity was almost completely removed to less than 0.2 NTU (below Chinese standard 1 NTU). It was found that PAC addition enhanced organic matter removal. The combined process of PAC/UF allowed to 41% removal of CODMn, 46% removal of DOC and 57% decrease in UV254 absorbance. The elimination of particles, from average 12000/ml in the raw water to approximately 15/ml in the permeated, was observed. When PAC concentration was below 30 mg/L, backwashing could recovery the membrane flux with backwash interval/backwashing duration of 1/30. 展开更多
关键词 surface water drinking water treatment ULTRAFILTRATION powdered activated carbon
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Role of adipokines and peroxisome proliferator-activated receptors in nonalcoholic fatty liver disease 被引量:30
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作者 Vettickattuparambil George Giby Thekkuttuparambil Ananthanarayanan Ajith 《World Journal of Hepatology》 CAS 2014年第8期570-579,共10页
Intrahepatic fat deposition has been demonstrated in patients with nonalcoholic fatty liver disease(NAFLD). Genetic and environmental factors are important for the development of NAFLD. Diseases such as obesity, diabe... Intrahepatic fat deposition has been demonstrated in patients with nonalcoholic fatty liver disease(NAFLD). Genetic and environmental factors are important for the development of NAFLD. Diseases such as obesity, diabetes, and hypertension have been found to be closely associated with the incidence of NAFLD. Evi-dence suggests that obesity and insulin resistance are the major factors that contribute to the development of NAFLD. In comparing the factors that contribute to the buildup of excess calories in obesity, an imbalance of energy homeostasis can be considered as the basis. Among the peripheral signals that are generated to regulate the uptake of food, signals from adipose tissue are of major relevance and involve the maintenance of energy homeostasis through processes such as lipo-genesis, lipolysis, and oxidation of fatty acids. Advances in research on adipose tissue suggest an integral role played by adipokines in NAFLD. Cytokines secreted by adipocytes, such as tumor necrosis factor-α, transform-ing growth factor-β, and interleukin-6, are implicated in NAFLD. Other adipokines, such as leptin and adiponectin and, to a lesser extent, resistin and retinol binding protein-4 are also involved. Leptin and adiponectin can augment the oxidation of fatty acid in liver by activating the nuclear receptor super-family of transcription fac-tors, namely peroxisome proliferator-activated receptor(PPAR)-α. Recent studies have proposed downregula-tion of PPAR-α in cases of hepatic steatosis. This re-view discusses the role of adipokines and PPARs with regard to hepatic energy metabolism and progression of NAFLD. 展开更多
关键词 NONALCOHOLIC FATTY liver disease ADIPOSE tissue Energy HOMEOSTASIS PEROXISOME proliferator activated receptors ADIPOKINES
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Behaviors and kinetics of toluene adsorption-desorption on activated carbons with varying pore structure 被引量:29
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作者 Xi Yang Honghong Yi +5 位作者 Xiaolong Tang Shunzheng Zhao Zhongyu Yang Yueqiang Ma Tiecheng Feng Xiaoxu Cui 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第5期104-114,共11页
This work was undertaken to investigate the behaviors and kinetics of toluene adsorption and desorption on activated carbons with varying pore structure. Five kinds of activated carbon from different raw materials wer... This work was undertaken to investigate the behaviors and kinetics of toluene adsorption and desorption on activated carbons with varying pore structure. Five kinds of activated carbon from different raw materials were selected. Adsorption isotherms and breakthrough curves for toluene were measured. Langmuir and Freundlich equations were fitted to the equilibrium data, and the Freundlich equation was more suitable for simulating toluene adsorption. The process consisted of monolayer, multilayer and partial active site adsorption types. The effect of the pore structure of the activated carbons on toluene adsorption capacity was investigated. The quasi-first-order model was more suitable for describing the process than the quasi-second-order model. The adsorption data was also modeled by the internal particle diffusion model and it was found that the adsorption process could be divided into three stages. In the external surface adsorption process, the rate depended on the specific surface area. During the particle diffusion stage, pore structure and volume were the main factors affecting adsorption rate. In the final equilibrium stage, the rate was determined by the ratio of meso-and macro-pores to total pore volume. The rate over the whole adsorption process was dominated by the toluene concentration. The desorption behavior of toluene on activated carbons was investigated,and the process was divided into heat and mass transfer parts corresponding to emission and diffusion mechanisms, respectively. Physical adsorption played the main role during the adsorption process. 展开更多
关键词 activated carbon TOLUENE Adsorption DESORPTION KINETICS
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Start-up of anaerobic ammonia oxidation bioreactor with nitrifying activated sludge 被引量:26
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作者 ZHENGPing LINFeng-mei +1 位作者 HUBao-lan CHENJian-song 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第1期13-16,共4页
The anaerobic ammonia oxidation(Anammox) bioreactor was successfully started up with the nitrifying activated sludge. After anaerobically operated for 105 d, the bioreactor reached a good performance with removal perc... The anaerobic ammonia oxidation(Anammox) bioreactor was successfully started up with the nitrifying activated sludge. After anaerobically operated for 105 d, the bioreactor reached a good performance with removal percentage of both ammonia and nitrite higher than 95% and volumetric total nitrogen removal as high as 149.55 mmol/(L·d). The soft padding made an important contribution to the high efficiency and stability because it held a large amount of biomass in the bioreactor. 展开更多
关键词 Anammox bioreactor nitrifying activated sludge START-UP
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Denitrifying phosphorus removal in a step-feed CAST with alternating anoxic-oxic operational strategy 被引量:28
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作者 MA Juan PENG Yongzhen +3 位作者 WANG Shuying WANG Li LIU Yangt MA Ningpin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第9期1169-1174,共6页
A bench-scale cyclic activated sludge technology (CAST) was operated to study the biological phosphorus removal performance and a series of batch tests was carried out to demonstrate the accumulation of denitrifying... A bench-scale cyclic activated sludge technology (CAST) was operated to study the biological phosphorus removal performance and a series of batch tests was carried out to demonstrate the accumulation of denitrifying polyphosphate-accumulating organisms (DNPAOs) in CAST system. Under all operating conditions, step-feed CAST with enough carbon sources in influent had the highest nitrogen and phosphorus removal efficiency as well as good sludge settling performance. The average removal rate of COD, NH4^+-N, PO4^3--P and total nitrogen (TN) was 88.2%, 98.7%, 97.5% and 92.1%, respectively. The average sludge volume index (SVI) was 133 mL/g. The optimum anaerobic/aerobic/anoxic (AOA) conditions for the cultivation of DNPAOs could be achieved by alternating anoxic/oxic operational strategy, thus a significant denitrifying phosphorus removal occurred in step-feed CAST. The denitrification of NO^x--N completed quickly due to step-feed operation and enough carbon sources, which could enhance phosphorus release and further phosphorus uptake capability of the system. Batch tests also proved that polyphosphate-accumulating organisms (PAOs) in the step-feed process had strong denitrifying phosphorus removal capacity. Both nitrate and nitrite could be used as electron acceptors in denitrifying phosphorus removal. Low COD supply with step-feed operation strategy would favor DNPAOs accumulation. 展开更多
关键词 cyclic activated sludge technology biological phosphorus removal denitrifying polyphosphate-accumulating organisms
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Activated carbon adsorption of quinolone antibiotics in water:Performance,mechanism,and modeling 被引量:29
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作者 Hao Fu Xuebing Li +4 位作者 Jun Wang Pengfei Lin Chao Chen Xiaojian Zhang I.H.(Mel)Suffet 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第6期145-152,共8页
The extensive use of antibiotics has led to their presence in the aquatic environment, and introduces potential impacts on human and ecological health. The capability of powdered activated carbon (PAC) to remove six... The extensive use of antibiotics has led to their presence in the aquatic environment, and introduces potential impacts on human and ecological health. The capability of powdered activated carbon (PAC) to remove six frequently used quinolone (QN) antibiotics during water treatment was evaluated to improve drinking water safety. The kinetics of QN adsorption by PAC was best described by a pseudo second-order equation, and the adsorption capacity was well described by the Freundlich isotherm equation. Isotherms measured at different pH showed that hydrophobic interaction, electrostatic interaction, and dispersion force were the main mechanisms for adsorption of QNs by PAC. A pH-dependent isotherm model based on the Freundlich equation was developed to predict the adsorption capacity of QNs by PAC at different pH values. This model had excellent prediction capabilities under different laboratory scenarios. Small relative standard derivations (RSDs), i.e., 0.59%-0.92% for ciprofloxacin and 0.09%-3.89% for enrofloxacin, were observed for equilibrium concentrations above the 0.3 mg/L level. The RSDs increased to 11.9% for ciprofloxacin and 32.1% for enrofloxacin at μg/L equilibrium levels, which is still acceptable. This model could be applied to predict the adsorption of other chemicals having different ionized forms. 展开更多
关键词 Quinolone antibioticsPowdered activated carbonAdsorptionpH-dependent isotherm model
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Hepatitis B virus,HBx mutants and their role in hepatocellular carcinoma 被引量:30
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作者 Ashraf Ali Hany Abdel-Hafiz +7 位作者 Mohd Suhail Amany Al-Mars Mohammad Khalid Zakaria Kaneez Fatima Sultan Ahmad Esam Azhar Adeel Chaudhary Ishtiaq Qadri 《World Journal of Gastroenterology》 SCIE CAS 2014年第30期10238-10248,共11页
Hepatocellular carcinoma(HCC)is one of the leading causes of death induced by cancer in the modern world and majority of the cases are related to chronic hepatitis B virus(HBV)infection.HBV-encoded X protein(HBx)is kn... Hepatocellular carcinoma(HCC)is one of the leading causes of death induced by cancer in the modern world and majority of the cases are related to chronic hepatitis B virus(HBV)infection.HBV-encoded X protein(HBx)is known to play a pivotal role in the pathogenesis of viral induced HCC.HBx is a multifunctional protein of17 kDa which modulates several cellular processes by direct or indirect interaction with a repertoire of host factors resulting in HCC.HBX might interfere with several cellular processes such as oxidative stress,DNA repair,signal transduction,transcription,protein degradation,cell cycle progression and apoptosis.A number of reports have indicated that HBx is one of the most common viral ORFs that is often integrated into the host genome and its sequence variants play a crucial role in HCC.By mutational or deletion analysis it was shown that carboxy terminal of HBx has a likely role in protein-protein interactions,transcriptional transactivation,DNA repair,cell,signaling and pathogenesis of HCC.The accumulated evidence thus far suggests that it is difficult to understand the mechanistic nature of HBx associated HCC,and HBx mediated transcriptional transactivation and signaling pathways may be a major determinant.This article addresses the role of HBx in the development of HCC with particular emphasis on HBx mutants and their putative targets. 展开更多
关键词 Hepatitis B virus Hepatocellular carcinoma Transcription factors Apoptosis EPIGENETICS MUTANTS Tumor necrosis factor activating protein Transforming growth factor Mitogen activated protein kinase
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Modification of Activated Carbon Fiber by Loading Metals and Their Performance on SO2 Removal 被引量:27
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作者 王建英 赵风云 +2 位作者 胡永琪 赵瑞红 刘润静 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第4期478-485,共8页
Metal-loaded activated carbon fibers (ACFs) were prepared by impregnation and characterized by N2 adsorption at 77K, XRD, XPS and SEM. Their properties on SO2 removal were examined in a tubular fixed bed reactor wit... Metal-loaded activated carbon fibers (ACFs) were prepared by impregnation and characterized by N2 adsorption at 77K, XRD, XPS and SEM. Their properties on SO2 removal were examined in a tubular fixed bed reactor with a model flue gas. Cobalt-loaded ACF showed the best activity among the prepared metal-loaded ACFs and a constant removal ratio of SO2 above 87% during continuous exposure to the flow of SO2/O2/H2O/N2 at 45℃ for more than 216h. The characteristic of the prepared loaded-ACFs showed that the exceptional activity of Co-ACF was attributed to the high amount of active sites due to modification by loading cobalt. 展开更多
关键词 activated carbon fiber IMPREGNATION adsorption properties
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Tb^(3+)激活硅酸盐玻璃的发光性能及其X射线转换屏应用研究 被引量:19
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作者 祖成奎 陈洁 《硅酸盐学报》 EI CAS CSCD 北大核心 2004年第3期283-286,298,共5页
通过成分设计、试样制备得到了荧光性能良好的Tb3+ 激活硅酸盐发光玻璃 ,利用荧光光度计测试了玻璃的激发光谱和发射光谱 ,在能量为 9MeV的X射线电荷耦合器件 (charge coupleddevice,CCD)摄像系统中 ,比较了Tb3+ 激活硅酸盐玻璃转换屏与... 通过成分设计、试样制备得到了荧光性能良好的Tb3+ 激活硅酸盐发光玻璃 ,利用荧光光度计测试了玻璃的激发光谱和发射光谱 ,在能量为 9MeV的X射线电荷耦合器件 (charge coupleddevice,CCD)摄像系统中 ,比较了Tb3+ 激活硅酸盐玻璃转换屏与Gd2 O2 S∶Tb多晶转换屏的发光性能。结果表明 :在Tb3+ 激活硅酸盐发光玻璃的发射波长中 ,5 43nm处的绿光发射最强 ,并且在X射线和紫外线的激发下 ,发射峰有不同程度的分裂。当Tb3+ 浓度增加时 ,由于能量在Tb3+ 离子间发生了无辐射共振转移 ,发光玻璃的蓝色荧光减弱 ,绿色荧光增强。发光玻璃在X射线CCD摄像系统中的使用效果良好 ,成像质量较高 ,可望作为X射线转换屏在CCD摄像系统中获得应用。 展开更多
关键词 铽离子 激活 硅酸盐玻璃 发光性能 X射线转换屏
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Comparison of bacterial community structures in two systems of a sewage treatment plant using PCR-DGGE analysis 被引量:25
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作者 Abd El-Latif Hesham Rong Qi Min Yang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第12期2049-2054,共6页
The combination of PCR amplification of 16S rRNA genes with denaturing gradient gel electrophoresis (DGGE) analysis was used to reveal the compositions and dynamics of bacterial communities in a sewage treatment pla... The combination of PCR amplification of 16S rRNA genes with denaturing gradient gel electrophoresis (DGGE) analysis was used to reveal the compositions and dynamics of bacterial communities in a sewage treatment plant with two systems, i.e., an anoxic- anaerobic-aerobic system (inverted A2O) and an anaerobic-anoxic-aerobic one (conventional A2O) over a period from February to July 2009, during which both systems experienced serious sludge bulking problems. The DGGE patterns showed that there were many common bands in both systems, suggesting the high similarity of bacterial communities of the two systems. Meanwhile, the moving window correlation analysis showed that the two systems experienced different microbial community structure changes during the period, which might be related with the different situations of the occurrence and disappearance of sludge bulking, as being reflected by sludge volume index (SVI) values. Major bands of DGGE patterns of sludge samples were further sequenced. Phylogenetic affiliation indicated that the majority of the sequences obtained were affiliated with Actinobacteria, Firmicutes, Bacteroidetes/Chlorobi group and α- and β-Proteobacteria. Two sequences showed high similarities to typical filamentous bacteria Microthrix parvicella and Nostocoida limicola I, indicating that these bacterial species have been involved in the sludge bulking problems. 展开更多
关键词 PCR-DGGE bacterial community activated sludge sludge bulking sewage treatment plant
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Influence of moderate pre-oxidation treatment on the physical, chemical and phosphate adsorption properties of iron-containing activated carbon 被引量:25
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作者 Zhengfang Wang Mo Shi +1 位作者 Jihua Li Zheng Zheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第3期519-528,共10页
A novel adsorbent based on iron oxide dispersed over activated carbon (AC) were prepared, and used for phosphate removal from aqueous solutions. The influence of pre-oxidation treatment on the physical, chemical and... A novel adsorbent based on iron oxide dispersed over activated carbon (AC) were prepared, and used for phosphate removal from aqueous solutions. The influence of pre-oxidation treatment on the physical, chemical and phosphate adsorption properties of iron-containing AC were determined. Two series of ACs, non-oxidized and oxidized carbon modified by iron (denoted as AC-Fe and AC/O- Fe), resulted in a maximum impregnated iron of 4.03% and 7.56%, respectively. AC/O-Fe showed 34.0%46.6% higher phosphate removal efficiency than the AC-Fe did. This was first attributed to the moderate pre-oxidation of raw AC by nitric acid, achieved by dosing Fe(II) after a pre-oxidation, to obtain higher iron loading, which is favorable for phosphate adsorption. Additionally, the in-situ formed active site on the surface of carbon, which was derived from the oxidation of Fe(II) by nitric acid dominated the remarkably high efficiency with respect to the removal of phosphate. The activation energy for adsorption was calculated to be 10.53 and 18.88 kJ/mol for AC-Fe and AC/O- Fe, respectively. The results showed that the surface mass transfer and intra-parficle diffusion were simultaneously occurring during the process and contribute to the adsorption mechanism. 展开更多
关键词 adsorption per-oxidation iron-containing activated carbonphos phatemechanism
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Changes of activated circulating endothelial cells and survivin in patients with non-small cell lung cancer after antiangiogenesis therapy 被引量:24
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作者 WANG Jing HUANG Chun +5 位作者 WEI Xi-yin QI Da-liang GONG Li-qun MU Hai-yu YAO Qiang LI Kai 《Chinese Medical Journal》 SCIE CAS CSCD 2008年第22期2234-2240,共7页
Background Although antiangiogenesis therapy plays an important role in anti-neoplastic treatment with its recognized efficacy and slight adverse effect, there is no prospective clinical trial to define ideal markers ... Background Although antiangiogenesis therapy plays an important role in anti-neoplastic treatment with its recognized efficacy and slight adverse effect, there is no prospective clinical trial to define ideal markers for predicting efficacy of antiangiogenic therapy. This study was undertaken to investigate the changes of activated circulating endothelial cells (aCECs) and survivin after anti-angiogenesis therapy and their significance in predicting the efficacy of the therapy. Methods Patients of non-small cell lung cancer (NSCLC) treated with chemotherapy with or without Endostar were observed. The amount of activated CECs was detected by flow cytometry, and the expression of survivin mRNA was determined by real-time polymerase chain reaction (PCR). Results After treatment, the amount of activated CECs decreased significantly in clinical benefit cases (P=0.021 in chemotherapy alone, P=0.001 in chemotherapy plus Endostar), increased in disease progressive cases (P=0.015 in chemotherapy alone, but P=0.293 in chemotherapy with Endotatar). After therapy, the expression of survivin mRNA decreased in clinical benefit cases (P=0.001) and increased in disease progressive cases (P=0.018). A positive correlation was found between activated CECs and survivin in the chemotherapy group pre- and post-therapy (P=0.001 and 0.021, respectively), but only in the chemotherapy with Endostar group pre-therapy (P=0.030) rather than post-therapy. A positive correlation was found between the decreased activated CECs after therapy and time to progression (TTP) (r=0.322, P=0.012); a negative correlation was found between the amount of survivin mRNA in serum post-therapy and -l-I-P(r= -0.291, P=0.048). Conclusions Activated CECs and survivin may be ideal markers forecasting efficacy and prognosis of NSCLC. The former can reflect more sensitively antiangiogenic efficacy and the latter is more sensitive to shrinkage or swelling of tumors. Their combination can evaluate more accurately the eff 展开更多
关键词 ENDOSTAR activated circulating endothelial cells SURVIVIN non-small cell lung cancer
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Effect of Relative Humidity on Adsorption of Formaldehyde on Modified Activated Carbons 被引量:25
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作者 李晶 李忠 +2 位作者 刘冰 夏启斌 奚红霞 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第6期871-875,共5页
This work mainly involves the study of effect of relative humidity on adsorption of formaldehyde on the activated carbons modified with organosilane solution. Modification of activated carbons was carded out by impreg... This work mainly involves the study of effect of relative humidity on adsorption of formaldehyde on the activated carbons modified with organosilane solution. Modification of activated carbons was carded out by impregnating activated carbon with organosilane/methanol-containing solutions. The breakthrough curves of formaldehyde in the packed beds of original and modified activated carbons were measured, respectively, at relative humidity of 30%, 60%, and 80%. Temperature-programmed desorption (TPD) experiments were used to estimate the activation energy for desorption of formaldehyde from the activated carbon. Results showed that the relative humidity had strongly influence on breakthrough curves of formaldehyde in the packed beds. The higher the relative humidity of gas mixtures through the packed beds was, the smaller the breakthrough time of formaldehyde became. The use of organosilane compounds to modify surfaces of the activated carbon can enhance the interaction between formaldehyde and the surfaces, and as a result, the breakthrough times of formaldehyde in the packed beds of the modified activated carbon were longer than that in the packed bed of the unmodified activated carbon. 展开更多
关键词 activated carbon FORMALDEHYDE breakthrough curve desorption activation energy
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Microwave photocatalytic degradation of Rhodamine B using TiO_2 supported on activated carbon:Mechanism implication 被引量:23
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作者 HE Zhong,YANG Shaogui,JU Yongming,SUN Cheng State Key Laboratory of Pollution Control and Resource Reuse,School of the Environment,Nanjing University,Nanjing 210093,China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第2期268-272,共5页
The photocatalytic degradation of Rhodamine B (RhB) was carried out using TiO2 supported on activated carbon (TiO2-AC) under microwave irradiation. Composite catalyst TiO2-AC was prepared and characterized using X... The photocatalytic degradation of Rhodamine B (RhB) was carried out using TiO2 supported on activated carbon (TiO2-AC) under microwave irradiation. Composite catalyst TiO2-AC was prepared and characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET). In the process of microwave-enhanced photocatalysis (MPC), RhB (30 mg/L) was almost completely decoloured in 10 min, and the mineralization efficiency was 96.0% in 20 min. The reaction rate constant of RhB in MPC using TiO2-AC by pseudo first-order reaction kinetics was 4.16 times of that using Degussa P25. Additionally, according to gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS) identification, the major intermediates of RhB in MPC included two kinds of N-de-ethylation intermediates (N,N-diethyl-N'-ethyl-rhodamine (DER)), oxalic acid, malonic acid, snccinic acid, and phthalic acid, maleic acid, 3-nitrobenzoic acid, and so on. The degradation of RhB in MPC was mainly attributed to the destruction of the conjugated structure, and then the intermediates transformed to acid molecules which were mineralized to water and carbon dioxide. 展开更多
关键词 microwave photocatalytic WiO2 activated carbon Rhodamine B degradation mechanism
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