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Study of steam heat transfer enhanced by CO_(2) and chemical agents: In heavy oil production 被引量:1
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作者 Ya-Li Liu Chao Zhang +1 位作者 Song-Yan Li Zhao-Min Li 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1030-1043,共14页
Steam flooding with the assistance of carbon dioxide (CO_(2)) and chemicals is an effective approach for enhancing super heavy oil recovery. However, the promotion and application of CO_(2) and chemical agent-assisted... Steam flooding with the assistance of carbon dioxide (CO_(2)) and chemicals is an effective approach for enhancing super heavy oil recovery. However, the promotion and application of CO_(2) and chemical agent-assisted steam flooding technology have been restricted by the current lack of research on the synergistic effect of CO_(2) and chemical agents on enhanced steam flooding heat transfer. The novel experiments on CO_(2)–chemicals cooperate affected steam condensation and seepage were conducted by adding CO_(2) and two chemicals (sodium dodecyl sulfate (SDS) and the betaine temperature-salt resistant foaming agent ZK-05200).According to the experimental findings, a “film” formed on the heat-transfer medium surface following the co-injection of CO_(2) and the chemical to impede the steam heat transfer, reducing the heat transfer efficiency of steam, heat flux and condensation heat transfer coefficient. The steam seepage experiment revealed that the temperature at the back end of the sandpack model was dramatically raised by 3.5–12.8 °C by adding CO_(2) and chemical agents, achieving the goal of driving deep-formation heavy oil. The combined effect of CO_(2) and SDS was the most effective for improving steam heat transfer, the steam heat loss was reduced by 6.2%, the steam condensation cycle was prolonged by 1.3 times, the condensation heat transfer coefficient was decreased by 15.5%, and the heavy oil recovery was enhanced by 9.82%. Theoretical recommendations are offered in this study for improving the CO_(2)–chemical-assisted steam flooding technique. 展开更多
关键词 Steam flooding Heavy oil Carbon dioxide chemical agent Enhanced oil recovery(EOR) Heat transfer
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Multiple chemical warfare agent simulant decontamination by self-driven microplasma 被引量:1
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作者 陈恕彬 王世宇 +1 位作者 朱安娜 王瑞雪 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第11期12-21,共10页
Low-temperature plasma is a green and high-efficiency technology for chemical warfare agent(CWA)decontamination.However,traditional plasma devices suffer from the problems of highpower composition and large power-supp... Low-temperature plasma is a green and high-efficiency technology for chemical warfare agent(CWA)decontamination.However,traditional plasma devices suffer from the problems of highpower composition and large power-supply size,which limit their practical applications.In this paper,a self-driven microplasma decontamination system,induced by a dielectric-dielectric rotary triboelectric nanogenerator(dd-r TENG),was innovatively proposed for the decontamination of CWA simulants.The microplasma was characterized via electrical measurements,optical emission spectra and ozone concentration detection.With an output voltage of-3460 V,the dd-r TENG can successfully excite microplasma in air.Reactive species,such as OH,O(1D),Hαand O3were detected.With input average power of 0.116 W,the decontamination rate of 2-chloroethyl ethyl sulfide reached 100%within 3 min of plasma treatment,while the decontamination rates of malathion and dimethyl methylphosphonate reached(65.92±1.65)%and(60.88±1.92)%after 7 min of plasma treatment,respectively.In addition,the decontamination rates gradually decreased with the increase in the simulant concentrations.Typical products were identified and analyzed.This study demonstrates the broad spectrum and feasibility of the dd-r TENG-microplasma for CWA elimination,which provides significant guidance for their practical applications in the future. 展开更多
关键词 triboelectric nanogenerator MICROPLASMA DECONTAMINATION chemical warfare agents simulants(Some figures may appear in colour only in the online journal)
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Agent Blue: A Secret Military and Environmental Chemical Weapon Used for Food Denial in South Vietnam during the Vietnam Civil War (1962-1965)
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作者 Kenneth R. Olson 《Open Journal of Soil Science》 2023年第3期151-186,共21页
During the last 60 years, the southern Vietnam environment and Vietnamese living in the Mekong Delta have bio-accumulated arsenic from natural and anthropic (Vietnam Civil War (1962-1965)) sources via their drinking w... During the last 60 years, the southern Vietnam environment and Vietnamese living in the Mekong Delta have bio-accumulated arsenic from natural and anthropic (Vietnam Civil War (1962-1965)) sources via their drinking water (groundwater from tube wells) and food supply leading to an increasing risk of chronic poisoning over time. A synthesis and analysis of publications and records is presented to document the Republic of Vietnam (RV), the official name of the South Vietnam Government, and United States (US) militaries contribution to arsenic levels and toxic spikes in the Vietnam Mekong Delta groundwater. During the Vietnam Civil War, Agent Blue, in powder form, was shipped to Port Saigon, via the Saigon River, and transported to the Tan Son Nhut Air Force base during the Vietnam Civil War. After the official start of the American-Vietnam War (1965-1973) the tactical herbicides were re-routed to Bien Hoa Air Force base (1965 to 1971). Approximately 3.2 million liters of Agent Blue (468,008 kg As) was sprayed or dumped by the RV military with the assistance and support of the Central Intelligence (CIA), US Army and US Navy, during the 1962-1965 Khai Huang (Hamlet) Program. A portion of an additional 4.6 million liters of Agent Blue (664,392 kg of As) was sprayed between 1962 and 1965 by the US Air Force as part of Operation Ranch Hand and prior to the official start of the American-Vietnam War in August 1964. Operation Rand Hand began in 1962 and ended in 1971. The Institute of Medicine estimated a total of 7.8 million liters (1,132,400 kg As) of Agent Blue was applied to southern Vietnam landscape from 1962 to 1971. This total includes both the 1962 to 1965 RV Khai Huang program with the assistance of the CIA, US Army and US Navy, and the total Agent Blue applied by US Air Force Operation Ranch Hand from 1962 to 1971. The primary objective of this study was to document how Agent Blue, the arsenic-based herbicide, became a secret US military and environmental chemical weapon used by the RV and US militaries in southern Vietnam during the Vietnam Civil War years (1962-1965). This assessment found that the anthropic arsenic, including Agent Blue, added a toxic burden to the Mekong Delta soils, surface water, groundwater, drinking water, food supply, and human health. However, there are missing details regarding political decisions and a full accounting of the geographic locations sprayed and amount of Agent Blue used. Vietnam War Archives have paper correspondence and RV herbicide spray records that shed greater light on this period. These records are over 50 years old and need to be electronically scanned, stored, and made available for additional historical analyses. 展开更多
关键词 Arsenic Cacodylic Acid agent Blue Herbicides chemical Weapons Fort Detrick Department of Defense (DOD) President Kennedy President Diem CIA US State Department USDA Khai Huang
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Performance comparison of novel chemical agents in improving oil recovery from tight sands through spontaneous imbibition 被引量:4
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作者 Hai Huang Tayfun Babadagli +1 位作者 Xin Chen Huazhou Andy Li 《Petroleum Science》 SCIE CAS CSCD 2020年第2期409-418,共10页
Tight sands are abundant in nanopores leading to a high capillary pressure and normally a low fluid injectivity.As such,spontaneous imbibition might be an effective mechanism for improving oil recovery from tight sand... Tight sands are abundant in nanopores leading to a high capillary pressure and normally a low fluid injectivity.As such,spontaneous imbibition might be an effective mechanism for improving oil recovery from tight sands after fracturing.The chemical agents added to the injected water can alter the interfacial properties,which could help further enhance the oil recovery by spontaneous imbibition.This study explores the possibility of using novel chemicals to enhance oil recovery from tight sands via spontaneous imbibition.We experimentally examine the effects of more than ten different chemical agents on spontaneous imbibition,including a cationic surfactant(C12 TAB),two anionic surfactants(0242 and 0342),an ionic liquid(BMMIM BF4),a high pH solution(NaBO2),and a series of house-made deep eutectic solvents(DES3-7,9,11,and 14).The interfacial tensions(IFT)between oil phase and some chemical solutions are also determined.Experimental results indicate that both the ionic liquid and cationic surfactant used in this study are detrimental to spontaneous imbibition and decrease the oil recovery from tight sands,even though cationic surfactant significantly decreases the oil-water IFT while ionic liquid does not.The high pH NaBO2 solution does not demonstrate significant effect on oil recovery improvement and IFT reduction.The anionic surfactants(O242 and O342)are effective in enhancing oil recovery from tight sands through oil-water IFT reduction and emulsification effects.The DESs drive the rock surface to be more water-wet,and a specific formulation(DES9)leads to much improvement on oil recovery under counter-current imbibition condition.This preliminary study would provide some knowledge about how to optimize the selection of chemicals for improving oil recovery from tight reservoirs. 展开更多
关键词 SPONTANEOUS IMBIBITION NOVEL chemical agent Water FLOODING TIGHT SANDS
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Comparative Study on the Efficacies of 11 Chemical Agents against Taro Soft Rot Caused by Pectobacterium aroidearum 被引量:2
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作者 Dongkun Wang Xiuting Ji +8 位作者 Huaixu Zhan Chengpeng Zheng Hao Zong Xiaolei Tan Xiuchun Du Weimin Wang Jingjing Wu Fenglong Wang Xiaoqiang Wang 《Plant Diseases and Pests》 CAS 2021年第2期21-23,26,共4页
[Objective]The paper was to screen the effective agents for effectively controlling the occurrence and prevalence of taro soft rot.[Method]The fungicidal effects of 11 fungicides on taro soft rot were determined by in... [Objective]The paper was to screen the effective agents for effectively controlling the occurrence and prevalence of taro soft rot.[Method]The fungicidal effects of 11 fungicides on taro soft rot were determined by inhibition zone method.[Result]0.3%Tetramycin,25%bromothalonil,3%Zhongshengmycin and 30%zinc thiazole had better antifungal effect on Pectobacterium aroidearum at recommended concentration.The indoor toxicity of four fungicides showed that the EC50 of 0.3%tetramycin AS was the smallest of 0.6μg/mL,indicating that tetramycin had the largest toxicity and the best inhibitory effect against P.aroidearum;followed by 25%bromothalonil EC and 3%Zhongshengmycin WP,with the EC_(50) of 2.57 and 97.72μg/mL,respectively;the inhibitory effect of 30%zinc thiazole SC against P.aroidearum was the poorest.[Conclusion]The study provides a reference for screening out new and efficient chemical agents against taro soft rot. 展开更多
关键词 Taro soft rot Pectobacterium aroidearum EFFICACY EC_(50) chemical agents
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Study on scattering properties of tissues with hyperosmotic chemical agents
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作者 ZHOU Fujun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第3期250-255,共6页
Optical properties of biological tissue are variable due to the changes of micro-structures and scattering constituents after hyperosmotic chemical agents permeates into tissue. The changes of optical properties of bi... Optical properties of biological tissue are variable due to the changes of micro-structures and scattering constituents after hyperosmotic chemical agents permeates into tissue. The changes of optical properties of biological tissue are due to the refractive indices matching between the scatterers with high refractive index and the ground substances, which reduce scattering of tissue. The main reasons are that permeated semipermeable chemical agents with higher refractive index than the ground substances of tissue makes the refractive index of ground substances of tissue higher by the enhancement of the permeated concentration. We studied on the collimated transmittance changes of light penetrating biological tissue after the hyperosmotic chemical agents administrates with different concentration. 展开更多
关键词 optical properties osmotic action chemical agents
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Motility and Functional State of the Membrane of Caprine Capacitated Spermatozoa under Different Chemical Agents
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作者 A. Soberano Martínez J. Herrera Camacho J. C. Segura Correa 《Open Journal of Veterinary Medicine》 2012年第3期98-103,共6页
The objective of this study was to test the use of a commercial extender (Triladyl) as a diluent in caprine semen refrigerated at 15℃, using caffeine (CF), heparin (HP), synthetic oviductal fluid (SOF) andtriladyl (T... The objective of this study was to test the use of a commercial extender (Triladyl) as a diluent in caprine semen refrigerated at 15℃, using caffeine (CF), heparin (HP), synthetic oviductal fluid (SOF) andtriladyl (TRY) as capacitating chemical agents at different times. Twenty ejaculates of caprine semen were collected using an artificial vagina. The ejaculates were diluted and refrigerated by three days. Evaluated the progressive motility (PM) and the functional state of the sperm plasma membrane trough fluorescent CTC staining, counting 200 spermatic cells (non-capacitated spermatozoa NCS, capacitated CS and reacting spermatozoa REA) of caprine in two capacitating agents: CAF and HEP;one culture medium:SOF and a commercial extender: TRY at 60, 120, 180 and 240 min of incubation, during 24, 48 and 72 hs. PM was high under TRY, and CS was high under the HEP treatment. TRY could be an alternative to capacitate caprine spermatozoa, keeping PM for a longer time than HEP or CAF. 展开更多
关键词 SPERMATOZOA CAPACITATION CAPRINE chemical agents
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Laboratory investigation into the use of soundless chemical demolitions agents for the breakage of hard rock
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作者 Kelly‑Meriam Habib Isaac Vennes Hani Mitri 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第5期71-80,共10页
The method of drilling and blasting with explosives is widely used in rock fragmentation applications in the mining industry for mine development and ore production.However,the use of explosives is associated with rig... The method of drilling and blasting with explosives is widely used in rock fragmentation applications in the mining industry for mine development and ore production.However,the use of explosives is associated with rigorous safety and environmental constraints as blasting creates toxic fumes,ground vibrations,and dust.This study is focused on the use of Soundless Chemical Demolition Agents(SCDA)as a more environmentally friendly method for rock breakage and a potential replacement of explosives.In this paper,the results of a series of experimental tests are reported to identify the efect of SCDA on hard rock breakage under no load and under uniaxial loading conditions.Stanstead granite prismatic specimens of 152.4 mm(6″)×152.4–203.2 mm(6–8″)×406.4 mm(16″)are used to test the infuence of borehole size on the time to fracturing with SCDA borehole size of 25.4 mm(1″),31.75 mm(1.25″)and 38.1 mm(1.5″).It is shown that the fracturing time decreases with increasing borehole size.It is also shown that specimens subjected to uniaxial compression of 5 MPa fracture as early as 7 h after SCDA mixing.A borehole spacing to borehole diameter ratio of 12.8 to 14.6 is suggested for practical applications. 展开更多
关键词 Explosive-free Hard rock fragmentation Soundless chemical demolition agents Uniaxial loading
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A prototype portable instrument employing micro-preconcentrator and FBAR sensor for the detection of chemical warfare agents
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作者 Xu Yan Hemi Qu +2 位作者 Ye Chang Wei Pang Xuexin Duan 《Nanotechnology and Precision Engineering》 CAS CSCD 2022年第1期43-48,共6页
The presence of chemical warfare agents(CWAs)in the environment is a serious threat to human safety,but there are many problems with the currently available detection methods for CWAs.For example,gas chromatography–m... The presence of chemical warfare agents(CWAs)in the environment is a serious threat to human safety,but there are many problems with the currently available detection methods for CWAs.For example,gas chromatography–mass spectrometry cannot be used for in-field detection owing to the rather large size of the equipment required,while commercial sensors have the disadvantages of low sensitivity and poor selectivity.Here,we develop a portable gas sensing instrument for CWA detection that consists of a MEMSfabricated micro-preconcentrator(μPC)and a film bulk acoustic resonator(FBAR)gas sensor.The μPC is coated with a nanoporous metal–organic framework material to enrich the target,while the FBAR provides rapid detection without the need for extra carrier gas.Dimethyl methylphosphonate(DMMP),a simulant of the chemical warfare agent sarin,is used to test the performance of the instrument.Experimental results show that the μPC provides effective sample pretreatment,while the FBAR gas sensor has good sensitivity to DMMP vapor.The combination of μPC and FBAR in one instrument gives full play to their respective advantages,reducing the limit of detection of the analyte.Moreover,both the μPC and the FBAR are fabricated using a CMOS-compatible approach,and the prototype instrument is compact in size with high portability and thus has potential for application to in-field detection of CWAs. 展开更多
关键词 Micro-preconcentrator Film bulk acoustic resonator chemical warfare agent Microelectromechanical system
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Detection and Analysis of Chemical Agents in Sun-proof Products
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作者 Ma Ying Zhao Li +4 位作者 Li Zexiaqiong Nie Peng Liao Haiwei Liu Dan Qiu Hongyan 《China Detergent & Cosmetics》 2020年第4期40-43,共4页
15 chemical sunscreen agents in 220 batches of sun-proof products were tested,and the test results were checked with the product labels and approvals,and the problems found were compared and analyzed.There were some i... 15 chemical sunscreen agents in 220 batches of sun-proof products were tested,and the test results were checked with the product labels and approvals,and the problems found were compared and analyzed.There were some inconsistencies among the actual ingredients,labeling ingredients and approval ingredients in the sun-proof products on the market,and the problem of insufficient input of raw materials was prominent.The supervision of this kind of products should be strengthened so as to reduce the safety risk of consumers using this kind of products. 展开更多
关键词 sun-proof products chemical sunscreen agents DETECTION ANALYSIS
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Programmed cell death, antioxidant response and oxidative stress in wheat f lag leaves induced by chemical hybridization agent SQ-1 被引量:9
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作者 WANG Shu-ping ZHANG Gai-sheng +7 位作者 SONG Qi-lu ZHANG Ying-xin LI Ying GUO Jia-lin CHEN Zheng NIU Na MA Shou-cai WANG Jun-wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第1期76-86,共11页
Male sterility induced by a chemical hybridization agent (CHA) is an important tool for utilizing crop heterosis. Leaves, especially the flag leaves, as CHA initial recipients play a decisive role in inducing male s... Male sterility induced by a chemical hybridization agent (CHA) is an important tool for utilizing crop heterosis. Leaves, especially the flag leaves, as CHA initial recipients play a decisive role in inducing male sterility. To investigate effects of different treatment times of CHA-SQ-1 used, morphological, biochemical and physiological responses of wheat flag leaves were detected in thistudy. CHA induced programmed cell death (PCD) as shown in terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) and DNA laddering analysis. In the early phase, CHA-SQ-1 trig- gered organelle changes arid PCD in wheat leaves accompanied by excess production of reactive oxygen species (O2- and H202) and down-regulation of the activities of superoxide dismutase (SOD), catalase (CAT) and guaiacol peroxidase (POD). Meanwhile, leaf cell DNAs showed ladder-like patterns on agarose gel, indicating that CHA-SQ-1 led to the activation of the responsible endonuclease. The oxidative stress assays showed that lipid peroxidation was strongly activated and photosynthesis was obviously inhibited in SQ-l-induced leaves. However, CHA contents in wheat leaves gradually reduced along with the time CHA-SQ-1 applied. Young flags returned to an oxidative/antioxidative balance and ultimately developed into mature green leaves. These results provide explanation of the relations between PCD and anther abortion and practical application of CHA for hybrid breeding. 展开更多
关键词 wheat flag leaf chemical hybridization agent SQ-1 programmed cell death antioxidant response oxidative stress
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Decomposition kinetics of dimethyl methylphospate(chemical agent simulant) by supercritical water oxidation 被引量:2
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作者 Bambang VERIANSYAH Jae-Duck KIM Youn-Woo LEE 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第1期13-16,共4页
Supercritical water oxidation (SCWO) has been drawing much attention due to effectively destroy a large variety of high-risk wastes resulting from munitions demilitarization and complex industrial chemical. An impor... Supercritical water oxidation (SCWO) has been drawing much attention due to effectively destroy a large variety of high-risk wastes resulting from munitions demilitarization and complex industrial chemical. An important design consideration in the development of supercritical water oxidation is the information of decomposition rate. In this paper, the decomposition rate of dimethyl methylphosphonate(DMMP), which is similar to the nerve agent VX and GB(Sarin) in its structure, was investigated under SCWO conditions. The experiments were performed in an isothermal tubular reactor with a H2O2 as an oxidant. The reaction temperatures were ranged from 398 to 633℃ at a fixed pressure of 24 MPa. The conversion of DMMP was monitored by analyzing total organic carbon (TOC) on the liquid effluent samples. It is found that the oxidative decomposition of DMMP proceeded rapidly and a high TOC decomposition up to 99.99% was obtained within 11 s at 555℃. On the basis of data derived from experiments, a global kinetic equation for the decomposition of DMMP was developed. The model predictions agreed well with the experimental data. 展开更多
关键词 supercritical water oxidation kinetics chemical agent DMMP
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Effect of Top Slag Basicity on Quality of Steel Treated by Exothermic Agent SiFe and SiCaBa during Chemical Heating 被引量:1
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作者 WANG Hai-chuan ZHOU Yun +2 位作者 WANG Shi-jun YUE Ke-xiang DONG Yuan-chi 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2002年第1期12-15,共4页
The effect of top slag basicity on quality of steel treated with SiFe and SiCaBa alloy as exothermic agent in chemical heating was studied.These experiments were carried out in MoSi_2 laboratory furnace with 0.2 kg mo... The effect of top slag basicity on quality of steel treated with SiFe and SiCaBa alloy as exothermic agent in chemical heating was studied.These experiments were carried out in MoSi_2 laboratory furnace with 0.2 kg molten steel for equilibrium test and 2 kg molten steel for simulation test respectively.These results showed that the adjusting basicity of top slag with CaO is effective to prevent rephosphorization and resulphurization,and it is possible to dephosphorize and desulphurize and remove the inclusions from molten steel when basicity R of the top slag is adjusted to 2.0 — 3.10,and SiCaBa alloy is better than SiFe alloy in this relation. 展开更多
关键词 chemical heating top slag BASICITY SiFe SiCaBa exothermic agent
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Surface Decontamination of Chemical Agent Surrogates Using an Atmospheric Pressure Air Flow Plasma Jet 被引量:2
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作者 李战国 李颖 +1 位作者 曹鹏 赵红杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第7期696-701,共6页
An atmospheric pressure dielectric barrier discharge (DBD) plasma jet generator using air flow as the feedstock gas was applied to decontaminate the chemical agent surrogates on the surface of aluminum, stainless st... An atmospheric pressure dielectric barrier discharge (DBD) plasma jet generator using air flow as the feedstock gas was applied to decontaminate the chemical agent surrogates on the surface of aluminum, stainless steel or iron plate painted with alkyd or PVC. The experi- mental results of material decontamination show that the residual chemical agent on the material is lower than the permissible value of the National Military Standard of China. In order to test the corrosion effect of the plasma jet on different material surfaces in the decontamination pro-cess, corrosion tests for the materials of polymethyl methacrylate, neoprene, polyvinyl chloride (PVC), polyethylene (PE), phenolic resin, iron plate painted with alkyd, stainless steel, aluminum, etc. were carried out, and relevant parameters were examined, including etiolation index, chroma- tism, loss of gloss, corrosion form, etc. The results show that the plasma jet is slightly corrosive for part of the materials, but their performances are not affected. A portable calculator, computer display, mainboard, circuit board of radiogram, and a hygrometer could work normally after being treated by the plasma jet. 展开更多
关键词 surface decontamination chemical agents atmospheric pressure plasma jet dielectric barrier discharge (DBD) air flow dischargeDAF'~. co ~
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Chemicals Used in Polymeric Material Coated Waste Paper Composites
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作者 Zübeyde Bülbül Birol Üner 《Journal of Materials Science and Chemical Engineering》 2023年第5期1-10,共10页
In this research, at different quantities as fillers, Boric Acid, Calcite (CaCO<sub>3</sub>), SPT (Sodium Perborate Tetrahydrate) and as coupling matters, 3%, MAPE (Maleic Anhydride Grafted Polyethylene), ... In this research, at different quantities as fillers, Boric Acid, Calcite (CaCO<sub>3</sub>), SPT (Sodium Perborate Tetrahydrate) and as coupling matters, 3%, MAPE (Maleic Anhydride Grafted Polyethylene), Titanate and Silanyl (Vinyltriethoxysilane) were added waste paper. Composite boards were pressed and cut in 1 × 30 × 30 cm. In order to identify some properties of the produced boards, experimental works were applied according to the standards. In conclusion, bending stress reduced with filler materials and chemicals was reduced even more than the bending stress except for some experimental groups. In addition, it was observed that the coupling chemicals increased the bending strength and modulus of elasticity compared to the fillers. 展开更多
关键词 Matching chemicals Paper Composites Filling Materials POLYMERS Coupling agents Paper Fibers
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Effect of Shrinkage Reducing Agent and Steel Fiber on the Fluidity and Cracking Performance of Ultra-High Performance Concrete
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作者 Yong Wan Li Li +4 位作者 Jiaxin Zou Hucheng Xiao Mengdi Zhu Ying Su Jin Yang 《Fluid Dynamics & Materials Processing》 EI 2024年第9期1941-1956,共16页
Due to the low water-cement ratio of ultra-high-performance concrete(UHPC),fluidity and shrinkage cracking are key aspects determining the performance and durability of this type of concrete.In this study,the effects ... Due to the low water-cement ratio of ultra-high-performance concrete(UHPC),fluidity and shrinkage cracking are key aspects determining the performance and durability of this type of concrete.In this study,the effects of different types of cementitious materials,chemical shrinkage-reducing agents(SRA)and steel fiber(SF)were assessed.Compared with M2-UHPC and M3-UHPC,M1-UHPC was found to have better fluidity and shrinkage cracking performance.Moreover,different SRA incorporation methods,dosage and different SF types and aspect ratios were implemented.The incorporation of SRA and SF led to a decrease in the fluidity of UHPC.SRA internal content of 1%(NSRA-1%),SRA external content of 1%(WSRA-1%),STS-0.22 and STE-0.7 decreased the fluidity of UHPC by 3.3%,8.3%,9.2%and 25%,respectively.However,SRA and SF improved the UHPC shrinkage cracking performance.NSRA-1%and STE-0.7 reduced the shrinkage value of UHPC by 40%and 60%,respectively,and increased the crack resistance by 338%and 175%,respectively.In addition,the addition of SF was observed to make the microstructure of UHPC more compact,and the compressive strength and flexural strength of 28 d were increased by 26.9%and 19.9%,respectively. 展开更多
关键词 Ultra-high performance concrete chemical shrinkage reducing agent steel fiber shrinkage cracking repair and reinforcement
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Chemical Reaction Between Polyvinyl Alcohol and Titanate Coupling Agent with X-Ray Photoelectron Spectroscopy
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作者 李北星 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2003年第2期71-74,共4页
The chemical reaction between polyvinyl alcohol (PVA) and tri(dioctylpyrophosphoryloxy) isopropyl titanate (NDZ-201) was studied using X-ray photoelectron spectroscopy (XPS).The results show that some C-OH functional ... The chemical reaction between polyvinyl alcohol (PVA) and tri(dioctylpyrophosphoryloxy) isopropyl titanate (NDZ-201) was studied using X-ray photoelectron spectroscopy (XPS).The results show that some C-OH functional groups of PVA react with the titanate coupling agent to form C PVA-O-Ti-O-C PVA bond.The cross-linking of the PVA chains occurs through the formation of C PVA-O-Ti-O-C PVA bonds and produces a three dimensional hydrophobic polymer network.Accordingly,the mechanism is proposed that the titanate coupling agent improves the moisture sensitivity of high alumina cement/polyvinyl alcohol (HAC/PVA) based macro defect free (MDF) composite material. 展开更多
关键词 PVA titanate coupling agent chemical bond moisture sensitivity MECHANISM
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Effect of Boschniakia rossica on expression of GSTP,p53 and p21^(ras)proteins in early stage of chemical hepatocarcinogenesis and its anti-inflammatory activities in rats 被引量:33
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作者 Zong Zhu Yin Hai Ling Jin Xue Zhe Yin Tian Zhu Li Ji Shu Quan Zeng Nan Jin Institute for Cancer Research,Yanbian University College of Medicine,Yanji 133000,Jilin Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第6期812-818,共7页
AIM To investigate the effect of Boschniakiarossica(BR)extract on expression of GST-P,p53 and p21<sup>ras</sup>proteins in early stage of chemicalhepatocarcinogenesis in rats and its anti-inflammatory ac... AIM To investigate the effect of Boschniakiarossica(BR)extract on expression of GST-P,p53 and p21<sup>ras</sup>proteins in early stage of chemicalhepatocarcinogenesis in rats and its anti-inflammatory activities.METHODS The expression of tumor marker-placental form glutathione S-transferase(GST-P),p53 and p21<sup>ras</sup>proteins were investigated byimmunohistochemical techniques and ABCmethod.Anti-inflammatory activities of BR werestudied by xylene and croton oil-induced mouseear edema,carrageenin,histamine and hotscald-induced rat pow edema,adjuvant-inducedrat arthritis and cotton pellet-induced mousegranuloma formation methods.RESULTS The 500 mg/kg of BR-H<sub>2</sub>O extractfractionated from BR-Methanol extract hadinhibitory effect on the formation of DEN-inducedGST-P-positive foci in rat liver(GST-P stainingwas 78% positive in DEN+AAF group vs 20%positive in DEN+AAF+BR group,P【0.05)andthe expression of mutant p53 and p21<sup>ras</sup>proteinwas lower than that of hepatic preneoplasticlesions(33% and 22% positive respectively inDEN+AAF group vs negative in DEN+AAF+BRgroup).Both CH<sub>2</sub>Cl<sub>2</sub> and H<sub>2</sub>O extracts from BRhad anti-inflamatory effect in xylene and crotonoil-induced mouse ear edema(inhibitory rateswere 26%-29% and 35%-59%,respectively). BR-H<sub>2</sub>O extract exhibited inhibitory effect incarrageenin,histamine and hot scald-inducedhind paw edema and adjuvant-induced arthritis inrats and cotton pellet-induced granulomaformation in mice.CONCLUSION BR extract exhibited inhibitory effect on formation of preneoplastic hepatic foci in early stage of rat chemical hepato-carcinogenesis. Both CH<sub>2</sub>CI<sub>2</sub> and H<sub>2</sub>O extracts from BR exerted anti-inflammatory effect in rats and mice. 展开更多
关键词 Boschniakia rossica liver neoplasms/chemically induced GLUTATHIONE TRANSFERASES protein P53 immunohistochemistry anti-inflammatory agents RATS
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Different oxidation routes for lattice oxygen recovery of double-perovskite type oxides LaSrFeCoO6 as oxygen carriers for chemical looping steam methane reforming 被引量:3
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作者 Kun Zhao Yang Shen +5 位作者 Zhen Huang Fang He Guoqiang Wei Anqing Zheng Haibin Li Zengli Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第3期501-509,共9页
Double-perovskite type oxide LaSrFeCoO(LSFCO) was used as oxygen carrier for chemical looping steam methane reforming(CL-SMR) due to its unique structure and reactivity. Two different oxidation routes,steam-oxidat... Double-perovskite type oxide LaSrFeCoO(LSFCO) was used as oxygen carrier for chemical looping steam methane reforming(CL-SMR) due to its unique structure and reactivity. Two different oxidation routes,steam-oxidation and steam-air-stepwise-oxidation, were applied to investigate the recovery behaviors of the lattice oxygen in the oxygen carrier. The characterizations of the oxide were determined by X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), hydrogen temperature-programmed reduction(H-TPR) and scanning electron microscopy(SEM). The fresh sample LSFCO exhibits a monocrystalline perovskite structure with cubic symmetry and high crystallinity, except for a little impurity phase due to the antisite defect of Fe/Co disorder. The deconvolution distribution of XPS patterns indicated that Co,and Fe are predominantly in an oxidized state(Feand Fe) and(Coand Co), while O 1s exists at three species of lattice oxygen, chemisorbed oxygen and physical adsorbed oxygen. The double perovskite structure and chemical composition recover to the original state after the steam and air oxidation, while the Co ion cannot incorporate into the double perovskite structure and thus form the CoO just via individual steam oxidation. In comparison to the two different oxidation routes, the sample obtained by steam-oxidation exhibits even higher CHconversion, CO and Hselectivity and stronger hydrogen generation capacity. 展开更多
关键词 DOUBLE-PEROVSKITE chemical looping Lattice oxygen Oxidizing agent Redox
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Protection of armoured vehicles against chemical, biological and radiological contamination 被引量:1
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作者 Adam Wisniewski Jacek Pirszel 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第2期384-392,共9页
The article presents problems related to mechanical protection of vehicles with different add-on armours against chemical,biological and radiological contamination.This applies to vehicles with additional passive,reac... The article presents problems related to mechanical protection of vehicles with different add-on armours against chemical,biological and radiological contamination.This applies to vehicles with additional passive,reactive and hybrid protection in the form of cassettes against piercing with anti-tank projectiles,piercing with their kinetic energy of impact,and as a result of chemical energy of shaped charges as well as explosively formed projectiles.It has been shown how increased ballistic protection of these vehicles at the same time reduces their decontaminability in various places of the vehicle due to the increased additional surface of the vehicle with cassettes.Prevention of contamination of these cassettes has been presented as a way of reducing hard to reach surface for decontamination and a method of insulating construction elements(stands),fixing these cassettes to the vehicle,from the environment to prevent contact with contaminated liquids and dusts.The selection of appropriate materials is shown,which may affect the improvement of the decontamination efficiency of the vehicle with such cassettes.This applies to the use of materials with low absorption of chemical warfare agents,which prevent the accumulation of large amounts of these agents on contaminated surfaces and improve the effectiveness of decontamination.It also shows how to ensure better access of the disinfectant to as much of the vehicle surface as possible,covered with cassettes that have been contaminated.It shows how a vehicle,in particular with such cassettes,can provide protection against radar detection when Radar Absorbent Material is used on vehicle cassettes. 展开更多
关键词 Protection of ERA CBR defence chemical warfare agents Vehicle decontamination Radar absorbent material Additive manufacturing
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