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Minimizing sperm oxidative stress using nanotechnology for breeding programs in rams
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作者 Alejandro Jurado‑Campos Pedro Javier Soria‑Meneses +5 位作者 Maria Arenas‑Moreira Carlos Alonso‑Moreno Virginia Rodriguez‑Robledo Ana Josefa Soler Jose Julian Garde Maria del Rocio Fernandez‑Santos 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2395-2410,共16页
Background Artificial insemination(AI)is a routine breeding technology in animal reproduction.Nevertheless,the temperature-sensitive nature and short fertile lifespan of ram sperm samples hamper its use in AI.In this ... Background Artificial insemination(AI)is a routine breeding technology in animal reproduction.Nevertheless,the temperature-sensitive nature and short fertile lifespan of ram sperm samples hamper its use in AI.In this sense,nanotechnology is an interesting tool to improve sperm protection due to the development of nanomaterials for AI,which could be used as delivery vehicles.In this work,we explored the feasibility of vitamin E nanoemulsion(NE)for improving sperm quality during transport.Results With the aim of evaluating this proposal,ejaculates of 7 mature rams of Manchega breed were collected by artificial vagina and extended to 60×10^(6)spz/mL in AndromedR.Samples containing control and NE(12 mmol/L)with and without exogenous oxidative stress(100μmol/L Fe2+/ascorbate)were stored at 22 and 15℃and motility(CASA),viability(YO-PRO/PI),acrosomal integrity(PNA-FITC/PI),mitochondrial membrane potential(Mitotracker Deep Red 633),lipoperoxidation(C11 BODIPY 581/591),intracellular reactive oxygen species(ROS)production and DNA status(SCSAR)monitored during 96 h.Our results show that NE could be used to maintain ram spermatozoa during transport at 15 and 22℃for up to 96 h,with no appreciable loss of kinematic and physiological characteristics of freshly collected samples.Conclusions The storage of ram spermatozoa in liquid form for 2-5 d with vitamin E nanoemulsions may lead more flexibility to breeders in AI programs.In view of the potential and high versatility of these nanodevices,further studies are being carried out to assess the proposed sperm preservation medium on fertility after artificial insemination. 展开更多
关键词 Breeding technology NANOEMULSIONS NANOtechnology Sperm oxidative stress Vitamin E
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Development in oxide metallurgy for improving the weldability of high -strength low-alloy steel-Combined deoxidizers and microalloying elements
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作者 Tingting Li Jian Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1263-1284,共22页
The mechanisms of oxide metallurgy include inducing the formation of intragranular acicular ferrite(IAF)using micron-sized inclusions and restricting the growth of prior austenite grains(PAGs)by nanosized particles du... The mechanisms of oxide metallurgy include inducing the formation of intragranular acicular ferrite(IAF)using micron-sized inclusions and restricting the growth of prior austenite grains(PAGs)by nanosized particles during welding.The chaotically oriented IAF and refined PAGs inhibit crack initiation and propagation in the steel,resulting in high impact toughness.This work summarizes the com-bined effect of deoxidizers and alloying elements,with the aim to provide a new perspective for the research and practice related to im-proving the impact toughness of the heat affected zone(HAZ)during the high heat input welding.Ti complex deoxidation with other strong deoxidants,such as Mg,Ca,Zr,and rare earth metals(REMs),can improve the toughness of the heat-affected zone(HAZ)by re-fining PAGs or increasing IAF contents.However,it is difficult to identify the specific phase responsible for IAF nucleation because ef-fective inclusions formed by complex deoxidation are usually multiphase.Increasing alloying elements,such as C,Si,Al,Nb,or Cr,con-tents can impair HAZ toughness.A high C content typically increases the number of coarse carbides and decreases the potency of IAF formation.Si,Cr,or Al addition leads to the formation of undesirable microstructures.Nb reduces the high-temperature stability of the precipitates.Mo,V,and B can enhance HAZ toughness.Mo-containing precipitates present good thermal stability.VN or V(C,N)is ef-fective in promoting IAF nucleation due to its good coherent crystallographic relationship with ferrite.The formation of the B-depleted zone around the inclusion promotes IAF formation.The interactions between alloying elements are complex,and the effect of adding dif-ferent alloying elements remains to be evaluated.In the future,the interactions between various alloying elements and their effects on ox-ide metallurgy,as well as the calculation of the nucleation effects of effective inclusions using first principles calculations will become the focus of oxide metallurgy. 展开更多
关键词 oxide metallurgy technology heat affected zone high-strength low-alloy steel intragranular acicular ferrite microalloying element
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Research Progress on the Bismuth Containing Complex Oxide in Photocatalystic Technology
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作者 Miao Yingchun Yang Huiqiong +1 位作者 Li Fengxi Liang Yiwei 《Meteorological and Environmental Research》 CAS 2015年第5期33-37,共5页
The photocatalytic degradation on the bismuth containing complex oxide was revised in detail including the synthesis and classification of photocatalyts, and then the photocatalytic reaction, scavenger, and the mechan... The photocatalytic degradation on the bismuth containing complex oxide was revised in detail including the synthesis and classification of photocatalyts, and then the photocatalytic reaction, scavenger, and the mechanism of reaction. In particular, the perspectives of photocatalytic degradation on the bismuth containing oxide were analyzed in detail. 展开更多
关键词 Bismuth containing complex oxides Photocatalytic technology REVIEW China
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Study on Enzymatic Hydrolysis Technology and Antioxidant Activity of Glutinous Rice Glutinous Enzymatic Processes and Antioxidant Activity
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作者 Hongrui LI Jinshen MAI +1 位作者 Mingsheng XU Jun TAO 《Agricultural Biotechnology》 CAS 2013年第4期57-60,共4页
[ Objective] This study aimed to investigate enzymatic hydrolysis technology of glutinous rice and the oxidation resistance activity of the enzymatic hydrolysis solution. [ Method ] White glutinous rice was hydrolyzed... [ Objective] This study aimed to investigate enzymatic hydrolysis technology of glutinous rice and the oxidation resistance activity of the enzymatic hydrolysis solution. [ Method ] White glutinous rice was hydrolyzed using four kinds of proteases including neutral protease, alkaline protease, papain and trypsin. Using the scavenging rate of hydroxyl radical ( ·OH) as an indicator and appropriate protease as hydrolytic enzyme, the effects of protein substrate concentration, enzyme dosage, enzymatic hydrolysis temperature and initial pH on the abilities of proteases to scavenge hydroxyl radical from enzymatic hydrolysis solution of glutinous rice were investigated. Based on single-factor test, L9 (34) orthogonal experimental design was adopted, to determine the optimal enzymatic hydrolysis condi- tions leading to the highest oxidation resistance activity of enzymatic hydrolysis solution. [ Result] The optimized process parameters for enzymatic hydrolysis of glu- tinous rice protein with neutral protease were: protein substrate concentration of 2%, enzyme dosage of 24 000 U/g protein (protein meter), enzymatic hydrolysis temperature of 55 ℃, initial pH of 8.0, and enzymatic hydrolysis duration of 0.5 h; under these conditions, the hydroxyl radical scavenging rate could reach 56. 05% ; protein substrate concentration, enzyme dosage, enzymatic hydrolysis temperature and initial pH had extremely significant effects on the hydroxyl radical scavenging rate. In addition, the activities of antioxidant peptides in glutinous rice hydrolysates were well maintained within a temperature range of 60 - 100℃. [Condusion] The study produced theoretical feasibility reference for the production of functional base powder by spray drying. 展开更多
关键词 Glutinous rice Enzymatic hydrolysis technology Bioactive peptides Hydroxyl radical oxidation resistance
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Multifunctional silicon-based light emitting device in standard complementary metal oxide semiconductor technology 被引量:2
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作者 王伟 黄北举 +1 位作者 董赞 陈弘达 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期677-683,共7页
A three-terminal silicon-based light emitting device is proposed and fabricated in standard 0.35 μm complementary metal-oxide-semiconductor technology. This device is capable of versatile working modes: it can emit ... A three-terminal silicon-based light emitting device is proposed and fabricated in standard 0.35 μm complementary metal-oxide-semiconductor technology. This device is capable of versatile working modes: it can emit visible to near infra-red (NIR) light (the spectrum ranges from 500 nm to 1000 nm) in reverse bias avalanche breakdown mode with working voltage between 8.35 V-12 V and emit NIR light (the spectrum ranges from 900 nm to 1300 nm) in the forward injection mode with working voltage below 2 V. An apparent modulation effect on the light intensity from the polysilicon gate is observed in the forward injection mode. Furthermore, when the gate oxide is broken down, NIR light is emitted from the polysilicon/oxide/silicon structure. Optoelectronic characteristics of the device working in different modes are measured and compared. The mechanisms behind these different emissions are explored. 展开更多
关键词 optoelectronic integrated circuit complementary metal-oxide-semiconductor technology silicon-based light emitting device ELECTROLUMINESCENCE
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CALS-Technology for Synthesis of Oxide Nanomaterials in Low-Temperature Plasm
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作者 Bessarabov Arkadiy Kvasyuk Aleksey +1 位作者 Kochetygov Aleksey Ivanov Mark 《材料科学与工程(中英文A版)》 2011年第3X期374-379,共6页
关键词 低温等离子体 纳米材料 CALS 材料合成 技术普及 氧化物 血浆 质量管理系统
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A novel advanced oxidation process to degrade organic pollutants in wastewater:Microwave-activated persulfate oxidation 被引量:41
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作者 YANG Shiying WANG Ping +3 位作者 YANG Xin WEI Guang ZHANG Wenyi SHAN Liang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第9期1175-1180,共6页
This article, for the first time, provides a novel advanced oxidation process based on sulfate radical (SO^4·-) to degrade organic pollutants in wastewater: microwave (MW)-activated persulfate oxidation (AP... This article, for the first time, provides a novel advanced oxidation process based on sulfate radical (SO^4·-) to degrade organic pollutants in wastewater: microwave (MW)-activated persulfate oxidation (APO) with or without active carbon (AC). Azo dye acid Orange 7 (AO7) is used as a model compound to investigate the high reactivity of MW-APO. It is found that AO7 (up to 1000 mg/L) is completely decolorized within 5-7 min under an 800 W MW furnace assisted-APO. In the presence of chloride ion (up to 0.50 mol/L), the decolorization is still 100% completed, though delayed for about 1-2 min. Experiments are made to examine the enhancement by AC. It is exciting to find that the 100% decolorization of AO7 (500 mg/L) is achieved within 3 min by MW-APO using 1.0 g/L AC as catalyst, while the degradation efficiency maintains at 50% by MW energy without persulfate after about 5 min. Besides the destruction of visible light chromophore band of AO7 (484 nm), during MW-APO, two bands in the ultraviolet region (228 nm and 310 nm) are rapidly broken down. The removal of COD is about 83%-95% for 500 mg/L AO7. SO^4·- is identified with quenching studies using specific alcohols. Both SO^4·- and ·OH could degrade AO7, but SO^4·- plays the dominant role. In a word, MW-APO AC is a new catalytic combustion technology for destruction of organic contamination even for high concentration. 展开更多
关键词 microwave-activated persulfate oxidation active carbon sulfate radical advanced oxidation technology
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Development of catalytic combustion and CO_(2)capture and conversion technology 被引量:4
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作者 Zhibin Yang Ze Lei +5 位作者 Ben Ge Xingyu Xiong Yiqian Jin Kui Jiao Fanglin Chen Suping Peng 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第3期377-382,共6页
Changes are needed to improve the efficiency and lower the CO_(2)emissions of traditional coal-fired power generation,which is the main source of global CO_(2)emissions.The integrated gasification fuel cell(IGFC)proce... Changes are needed to improve the efficiency and lower the CO_(2)emissions of traditional coal-fired power generation,which is the main source of global CO_(2)emissions.The integrated gasification fuel cell(IGFC)process,which combines coal gasification and high-temperature fuel cells,was proposed in 2017 to improve the efficiency of coal-based power generation and reduce CO_(2)emissions.Supported by the National Key R&D Program of China,the IGFC for nearzero CO_(2)emissions program was enacted with the goal of achieving near-zero CO_(2)emissions based on(1)catalytic combustion of the flue gas from solid oxide fuel cell(SOFC)stacks and(2)CO_(2)conversion using solid oxide electrolysis cells(SOECs).In this work,we investigated a kW-level catalytic combustion burner and SOEC stack,evaluated the electrochemical performance of the SOEC stack in H2O electrolysis and H2O/CO_(2)co-electrolysis,and established a multiscale and multi-physical coupling simulation model of SOFCs and SOECs.The process developed in this work paves the way for the demonstration and deployment of IGFC technology in the future. 展开更多
关键词 Integrated gasification fuel cell(IGFC) Catalytic combustion technology Solid oxide electrolysis cells
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Photocatalytic Oxidation Property of LaFe_(1-y)Cu_yO_3 and Study on Positron Annihilation
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作者 杨秋华 崔津津 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期74-76,共3页
Pervoskite-type oxides LaFe_ 1-yCu_yO_3 was prepared by citrate method. Using a fluorescent Hg lamp as irradiator, the degradation experiments of acid red 3B were carried out in the suspension system of LaFe_ 1-yCu_yO... Pervoskite-type oxides LaFe_ 1-yCu_yO_3 was prepared by citrate method. Using a fluorescent Hg lamp as irradiator, the degradation experiments of acid red 3B were carried out in the suspension system of LaFe_ 1-yCu_yO_3. The results show that the doped oxides LaFe_ 1-yCu_yO_3 have good photocatalytic oxidation property. With the study of positron annihilation, its photocatalytic activity is mainly related with defect structures resulted by doping. 展开更多
关键词 pervoskite-type oxides acid red 3B photocatalytic degradation positron annihilation technology
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Advanced Treatment of Biologically Treated Chemical Comprehensive Wastewater by Nano-TiO2 Photocatalytic Oxidation
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作者 Zhai Jian Jiang Chunhua Chen Feng 《Meteorological and Environmental Research》 CAS 2018年第3期105-108,共4页
Nano-TiO2 photocatalytic oxidation was used to perform the advanced treatment of biologically treated chemical comprehensive wastewater. The effects of reaction time,nano-TiO2 dosage and initial p H of the wastewater ... Nano-TiO2 photocatalytic oxidation was used to perform the advanced treatment of biologically treated chemical comprehensive wastewater. The effects of reaction time,nano-TiO2 dosage and initial p H of the wastewater on the removal rate of COD were tested. The GC/MS and EEM techniques were used to qualitatively analyze organic compounds in the wastewater before and after treatment. The result showed that after the biologically treated chemical comprehensive wastewater was treated by nano-TiO2 photocatalytic oxidation under the conditions of reaction time 3 h,nano-TiO2 dosage 8 g/L,and pH 8. 0,the effluent COD was 61. 9 mg/L and its removal rate was 63. 8%. Additionally,the species of organic pollutants reduced from 12 to 6. Meanwhile,the content of humic-like and fulvic-like substances dropped dramatically. 展开更多
关键词 Biologically treated chemical comprehensive wastewater NANO-TIO2 Photocatalytic oxidation technology Advanced treatment GC-MS EEM
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The Technology of Green Chemistry and Its Function in Redox Response and: Environmentally Friendly Technology for Sustainable Development: Assessment of Recent Findings
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作者 Meselu Eskezia Ayalew Thevabakthi Siluvai Muthu Arul Jeevan 《Advances in Chemical Engineering and Science》 CAS 2022年第3期131-144,共14页
Sustainability is the ability to nurture or support a process for a long time without compromising the needs of future generations. Rather, sustainable chemistry is a term that refers to the production of chemical pro... Sustainability is the ability to nurture or support a process for a long time without compromising the needs of future generations. Rather, sustainable chemistry is a term that refers to the production of chemical products and processes that reduce or eliminate the use and production of hazardous substances. Green chemistry creates alternative technologies that are safer for human health and the environment to prevent further damage to human health and the environment, such as reducing the release of hazardous chemicals into the air, leading to reduced lung damage. Although sustainable and environmentally friendly technologies have evolved in other areas of science, their use in redox reactions and industry is still in its early stages. The current review aims to highlight the need for green chemistry as a sustainable chemistry and its principles and its application to produce environmentally friendly industrial products and to reduce or stop the production of harmful intermediates and products during its synthesis process. 展开更多
关键词 Atom Economy Green Chemistry Green technology oxidation Reduction
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Formation of Platinum (Pt) Nanocluster Coatings on K-OMS-2 Manganese Oxide Membranes by Reactive Spray Deposition Technique (RSDT) for Extended Stability during CO Oxidation
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作者 Hector F. Garces Justin Roller +5 位作者 Cecil K. King’ondu Saminda Dharmarathna Roger A. Ristau Rishabh Jain Radenka Maric Steven L. Suib 《Advances in Chemical Engineering and Science》 2014年第1期23-35,共13页
Nanocluster formation of a metallic platinum (Pt) coating, on manganese oxide inorganic membranes impregnated with multiwall carbon nanotubes (K-OMS-2/MWCNTs), applied by reactive spray deposition technology (RSDT) is... Nanocluster formation of a metallic platinum (Pt) coating, on manganese oxide inorganic membranes impregnated with multiwall carbon nanotubes (K-OMS-2/MWCNTs), applied by reactive spray deposition technology (RSDT) is discussed. RSDT applies thin films of Pt nanoclusters on the substrate;the thickness of the film can be easily controlled. The K-OMS-2/MWCNTs fibers were enclosed by the thin film of Pt. X-ray diffraction (XRD), scanning electron microscopy/X-ray energy dispersive spectroscopy (SEM/XEDS), focus ion beam/scanning electron microscopy (FIB/SEM), transmission electron microscopy (TEM), and X-ray 3D micro-tomography (MicroXCT) which have been used to characterize the resultant Pt/K-OMS-2/MWCNTs membrane. The non-destructive characterization technique (MicroXCT) resolves the Pt layer on the upper layer of the composite membrane and also shows that the membrane is composed of sheets superimposed into stacks. The nanostructured coating on the composite membrane material has been evaluated for carbon monoxide (CO) oxidation. The functionalized Pt/K-OMS-2/MWCNTs membranes show excellent conversion (100%) of CO to CO2 at a lower temperature 200℃ compared to the uncoated K-OMS-2/MWCNTs. Moreover, the Pt/K-OMS-2/MWCNTs membranes show outstanding stability, of more than 4 days, for CO oxidation at 200℃. 展开更多
关键词 Manganese oxide Membrane PT Nanostructures REACTIVE Spray DEPOSITION technology (RSDT) Film DEPOSITION X-Ray Tomography
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High Performance SLED Fabricated by Pulsed Anodic Oxidation
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作者 高欣 薄报学 +2 位作者 张晶 李辉 曲轶 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第1期47-51,共5页
InGaAs/AlGaAs MQW superluminescent LED(SLED) is fabricated by using pulsed anodic oxidation and molecular beam epitaxy(MBE).The power and spectral output characteristics of three kinds of device structures are investi... InGaAs/AlGaAs MQW superluminescent LED(SLED) is fabricated by using pulsed anodic oxidation and molecular beam epitaxy(MBE).The power and spectral output characteristics of three kinds of device structures are investigated.An output power above 10 mW with FWHM of 18 nm is demonstrated at a current of 150 mA. 展开更多
关键词 脉冲阳极氧化 高性能材料 超辐射发光二极管 ALGAAS 输出功率 分子束外延 MBE技术 多量子阱
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Research on Treatment Technology for the Industrial Wastewaters with High Concentrationin China
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作者 Sun Peishi Qian Biao +3 位作者 Hong Pinjie Harada Yoshiaki Yang Ying Hao Yukun 《工程科学(英文版)》 2005年第4期68-73,共6页
By using the introduced CWO technology and its 200 L/d plant, more than 10 kinds of industrial wastewaters with high concentration in China, such as the waste liquor of coking, the black liquor of paper making, the wa... By using the introduced CWO technology and its 200 L/d plant, more than 10 kinds of industrial wastewaters with high concentration in China, such as the waste liquor of coking, the black liquor of paper making, the waste mother liquor of bio-pharmacy and so on, were treated in this test research. The results showed that the CWO technology and its equipment had a good applicability for treating the industrial wastewaters with high concentration in China. One set of CWO-20 m^3/d industrial plant, as a demonstration engineering installation of CWO technology, was independently designed, made and operated in Kunming city. During the running test, the CWO-20 m^3/d plant displayed a favorable treatment capability for the bio-degradedly difficult industrial wastewaters with high concentration. For the treatment of the waste liquor from coking and the black liquor of paper making, more than 99% of CODcr and NH3-N in the wastewater could be removed. The CWO-20 m^3/d plant could be run continuously and stably. The treated wastewater could meet the discharge standard and the treatment process with CWO technology shown up a good economic advantage. 展开更多
关键词 高浓度工业废水 湿式催化氧化法 废水处理 化学需氧量
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多发伤患者早期肠道菌群及其代谢产物氧化三甲胺的变化
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作者 梁亚鹏 尹江涛 +4 位作者 苗振军 魏法星 苗健烨 李利毛 陈双伟 《临床与病理杂志》 CAS 2024年第3期381-389,共9页
目的:多发伤患者一旦并发脓毒症和多器官功能障碍综合征则预后不良。本研究通过观察多发伤患者早期肠道菌群及其代谢产物氧化三甲胺的变化,探讨多发伤患者并发脓毒症和多器官功能障碍综合征的可能机制。方法:选取2023年4月至9月江苏大... 目的:多发伤患者一旦并发脓毒症和多器官功能障碍综合征则预后不良。本研究通过观察多发伤患者早期肠道菌群及其代谢产物氧化三甲胺的变化,探讨多发伤患者并发脓毒症和多器官功能障碍综合征的可能机制。方法:选取2023年4月至9月江苏大学附属医院收治的符合纳入标准的多发伤患者25例作为多发伤组,选取同期本院体检中心符合纳入标准的健康志愿者25例作为对照组。收集多发伤组伤后1周左右的粪便标本和血浆标本,同期收集对照组体检当天的粪便标本和血浆标本。通过16S rRNA高通量测序技术检测粪便标本,分析多发伤组和对照组肠道菌群的差异。采用高效液相色谱-质谱串联技术检测血浆标本,分析多发伤组和对照组血浆氧化三甲胺水平的差异。结果:多发伤组和对照组的肠道菌群构成存在明显差异。在菌门水平上,多发伤组变形菌门的相对丰度明显高于对照组(P<0.05);厚壁菌门和拟杆菌门的相对丰度明显低于对照组(P<0.05)。在菌属水平上,多发伤组大肠埃希菌属、致病肠球菌属、梭菌属、考拉杆菌属的相对丰度均明显高于对照组(均P<0.05),普氏菌属、双歧杆菌属、瘤胃菌属、乳杆菌属、粪球菌属、布劳特菌属、丁酸弧菌属的相对丰度均明显低于对照组(均P<0.05)。多发伤组血浆氧化三甲胺水平明显高于对照组(P<0.05)。结论:与健康人群相比,多发伤患者早期肠道菌群已发生变化,专性厌氧菌相对丰度下降,兼性厌氧菌相对丰度上升,有益共生菌相对丰度减少,机会致病菌相对丰度增加,这可能与多发伤患者并发脓毒症有关。血浆氧化三甲胺的水平升高可能与肠道菌群的变化和多发伤患者并发多器官功能障碍综合征有关。 展开更多
关键词 多发伤 肠道菌群 氧化三甲胺 高通量测序技术
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冷却工艺、填充溶剂对钙钛氧化物的微观形貌及光催化性能的影响
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作者 程卫桃 李济 胡其国 《中国陶瓷》 CAS CSCD 北大核心 2024年第6期36-41,共6页
以钛酸正丁酯和无水氯化钙为原料,采用水热法制备了不同显微形貌的钙钛氧化物粉体。研究了冷却工艺与填充剂种类对钙钛氧化相结构、显微形貌和光催化特性的影响。结果表明:当无外加填充溶剂引入,采用不同冷却工艺均可获得具有片状结构的... 以钛酸正丁酯和无水氯化钙为原料,采用水热法制备了不同显微形貌的钙钛氧化物粉体。研究了冷却工艺与填充剂种类对钙钛氧化相结构、显微形貌和光催化特性的影响。结果表明:当无外加填充溶剂引入,采用不同冷却工艺均可获得具有片状结构的CaTi_(2)O_(4)(OH)_(2)纯相;当分别引入20 mL乙醇或水作为填充溶剂时,制备的粉体相结构和微观形貌在不同的冷却工艺下存在较大差异,粉体的相结构和微观形貌经历了从无定型相的针网状形貌过渡到由纳米纤维聚积夹杂少量块状CaTiO_(3)物相组成的形貌,以及完全由具有片状结构的CaTi_(2)O_(4)(OH)_(2)物相过渡到具有片状结构的CaTi_(2)O_(4)(OH)_(2)以及少量方块状CaTiO_(3)组成的物相。光催化性能显示,引入20 mL乙醇作为填充溶剂,采用缓冷工艺制备的粉体在紫外可见光3 h下对罗丹明B的光催化效率最佳。 展开更多
关键词 钙钛氧化物 冷却工艺 溶剂组成 光催化性能
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典型有机磷阻燃剂对蓝藻的Hormesis效应及机制探究
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作者 沈洪艳 彭煜祺 +4 位作者 杨雷 李燕 刘雪薇 孙昊宇 唐量 《安全与环境学报》 CAS CSCD 北大核心 2024年第2期809-818,共10页
为探究有机磷阻燃剂(Organophosphate Flame Retardants,OPFRs)对蓝藻的毒性效应,以铜绿微囊藻为蓝藻受试模型,测定典型OPFRs{烷基OPFRs磷酸三乙酯(Triethyl Phosphate,TEP)和氯代OPFRs磷酸三(2-氯乙基)酯[Tris(2-Chloroethyl)Phosphate... 为探究有机磷阻燃剂(Organophosphate Flame Retardants,OPFRs)对蓝藻的毒性效应,以铜绿微囊藻为蓝藻受试模型,测定典型OPFRs{烷基OPFRs磷酸三乙酯(Triethyl Phosphate,TEP)和氯代OPFRs磷酸三(2-氯乙基)酯[Tris(2-Chloroethyl)Phosphate,TCEP]}对蓝藻生长及光合色素、氧化应激、细胞膜疏水性等相关生理指标的影响。结果显示,TEP与TCEP均对铜绿微囊藻的生长产生了低质量浓度促进、高质量浓度抑制的Hormesis效应,促进生长的质量浓度分别为6.80×10^(-4)~1.53×10^(-1)mg/L和5.87×10^(-5)~1.54×10^(-1)mg/L。相关生理指标变化显示,低质量浓度OPFRs通过提高光合色素的合成及调控活性氧的适当增加可刺激蓝藻增殖;相反,高质量浓度OPFRs则阻碍光合作用,对藻细胞产生氧化胁迫,进而改变细胞膜疏水性致使细胞膜受损,最终导致蓝藻大量死亡。研究结果表明,OPFRs能引发蓝藻生长的Hormesis效应,且氯代OPFRs比烷基OPFRs具有更明显的生物效应,在一定暴露质量浓度内具有促进蓝藻水华形成的潜在环境风险。研究可为OPFRs水生毒性和相应的环境风险评价提供数据基础和理论依据。 展开更多
关键词 环境科学技术基础学科 有机磷阻燃剂 铜绿微囊藻 Hormesis效应 光合作用 氧化应激
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我国苯乙烯合成技术研究进展
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作者 谭捷 《石油化工技术与经济》 CAS 2024年第1期54-58,共5页
苯乙烯是一种重要的有机化工产品,广泛应用于合成树脂和合成橡胶等领域。文章介绍了我国CO_(2)氧化乙苯脱氢、苯乙炔选择性加氢、甲苯和甲醇侧链烷基化等合成苯乙烯技术的研究进展,并提出了今后的发展建议。
关键词 苯乙烯 催化剂 氧化脱氢 选择性加氢 侧链烷基化 合成技术 研究进展
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基于应用场景的未来技术识别 被引量:1
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作者 谢俊杰 孙希科 +2 位作者 王智琦 韩盟 陈悦 《情报杂志》 北大核心 2024年第5期97-105,共9页
[研究目的]未来技术作为传统产业的转型动力及未来产业的形成基础,从技术的应用及其产业化视角出发,进行未来技术的识别与预测,对我国布局未来产业、增强发展优势具有重要意义。[研究方法]从技术单元与技术方案出发,构建基于应用场景的... [研究目的]未来技术作为传统产业的转型动力及未来产业的形成基础,从技术的应用及其产业化视角出发,进行未来技术的识别与预测,对我国布局未来产业、增强发展优势具有重要意义。[研究方法]从技术单元与技术方案出发,构建基于应用场景的未来技术识别模型。首先,利用LDA主题模型对专利的用途进行主题聚类,识别技术的主要应用场景;其次,利用KeyBERT算法从专利的标题和新颖性文本中提取技术方案关键词,从技术方案的新颖性、关联性和重要性出发,筛选前沿技术方案;最后,定义产生前沿技术方案的技术单元为潜在未来技术,构建“技术影响力-技术生长力”坐标图,进行未来技术识别。[研究结论]以固体氧化物燃料电池领域为例进行实证研究,识别出13项未来技术,主要为SOFC批量化制造、可控性运行和实际化应用的技术,揭示了识别方法的有效性。 展开更多
关键词 应用场景 未来技术 技术识别 技术方案 专利文本 固体氧化物燃料电池 KeyBERT算法 LDA
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含过氧键化合物在土壤及地下水PAHs污染修复中的应用进展 被引量:1
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作者 韩跃鸣 代朝猛 +2 位作者 段艳平 刘曙光 张亚雷 《材料导报》 EI CAS CSCD 北大核心 2024年第6期248-254,共7页
土壤及地下水中多环芳烃(PAHs)污染的修复治理是当前亟需解决的问题,其中基于含过氧键化合物的高级氧化技术由于对土壤及地下水中PAHs具有高效的降解能力,在近年来受到越来越多的关注。本文重点总结了过氧化氢、过硫酸盐以及过氧乙酸在... 土壤及地下水中多环芳烃(PAHs)污染的修复治理是当前亟需解决的问题,其中基于含过氧键化合物的高级氧化技术由于对土壤及地下水中PAHs具有高效的降解能力,在近年来受到越来越多的关注。本文重点总结了过氧化氢、过硫酸盐以及过氧乙酸在土壤及地下水中PAHs污染修复方面的研究,从过氧键断裂产生自由基的角度讨论了其活化机制与降解机理,探究了过氧乙酸在土壤及地下水中PAHs污染修复中的应用前景,分析了影响修复效率的主要外部因素。总体来看,不同活化方式所产生的自由基种类有所不同,对PAHs污染的修复效果也有所差异,与此同时,土壤及地下水复杂环境因素对修复效果有着重要的影响。因此在未来的研究中应开发新型活化材料,提高修复效果并降低二次污染,同时需针对不同的土壤及地下水环境选择合适的活化方式,采用表面活性剂增强氧化剂的修复范围,在过氧乙酸修复PAHs污染方面开展更深入的研究。含过氧键化合物修复PAHs污染土壤及地下水是一个值得深入研究的领域,未来具有广阔的应用前景,本综述为此提供了理论基础。 展开更多
关键词 高级氧化技术(AOPs) 过氧键 多环芳烃(PAHs) 土壤及地下水
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