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江苏省稻麦轮作系统产量和CH_(4)、N_(2)O排放对施氮的响应
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作者 马寅正 乔云发 +2 位作者 唐煜杰 吴钥 苗淑杰 《生态与农村环境学报》 北大核心 2026年第1期27-40,共14页
为探究江苏省稻麦轮作系统CH_(4)以及N_(2)O排放与氮肥用量之间的定量关系以及最佳施肥方案,基于多水平定量施氮试验对稻麦轮作种植模式N_(2)O以及CH_(4)排放和施氮的关系进行精确估算,构建稻麦轮作系统碳足迹(CF)与生态经济净收益(NEEB... 为探究江苏省稻麦轮作系统CH_(4)以及N_(2)O排放与氮肥用量之间的定量关系以及最佳施肥方案,基于多水平定量施氮试验对稻麦轮作种植模式N_(2)O以及CH_(4)排放和施氮的关系进行精确估算,构建稻麦轮作系统碳足迹(CF)与生态经济净收益(NEEB)模型,并提出施肥优化方案。田间试验于2022年11月至2023年10月进行,为稻麦轮作体系。麦季试验设置6个施氮水平处理,分别为N0(0 kg·hm^(-2))、N180(180 kg·hm^(-2))、N240(240 kg·hm^(-2))、N270(270 kg·hm^(-2))、N300(300 kg·hm^(-2))和N360(360 kg·hm^(-2))。稻季试验设置5个施氮水平处理,分别为N0(0 kg·hm^(-2))、N180(180 kg·hm^(-2))、N240(240 kg·hm^(-2))、N300(300 kg·hm^(-2))和N360(360 kg·hm^(-2)),同一施氮水平试验均在同一小区进行轮作。采用静态箱/气相色谱法连续监测农田中CH_(4)和N_(2)O排放量,并综合稻麦产量和全球增温潜势(GWP)对温室气体排放强度(GHGI)进行分析。结果表明,稻麦轮作系统N_(2)O排放随着施氮水平的提高而显著增加,N_(2)O的排放和施氮水平呈指数关系。甲烷排放随氮肥水平提高呈现先降低再升高的趋势,甲烷排放量和施氮水平的最佳拟合方程为一元三次函数,这表明适宜的施氮水平可以减少CH_(4)排放。在整个稻麦轮作周期内,随着施氮量的增加,N_(2)O对GWP的贡献率逐步提升,CH_(4)的贡献率进一步下降,各氮肥处理稻季CH_(4)排放对GWP的贡献率始终占主导地位。因此,在稻麦轮作系统温室气体减排的研究中应该重点关注稻季CH_(4)排放。综合稻麦产量与全球增温潜势,协同构建碳足迹与生态经济净收益模型,分析表明267~283 kg·hm^(-2)的施氮量为最优施肥方案。 展开更多
关键词 稻麦轮作系统 施氮 CH_(4)排放 N_(2)o排放 碳足迹 生态经济效益
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基于Meta分析的氮肥施用对我国粮田N_(2)O和CH_(4)排放影响研究
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作者 韩莹 张思源 +2 位作者 刘宇 闫秋艳 闫双堆 《核农学报》 北大核心 2026年第2期394-403,I0001-I0004,共14页
为探明氮肥对我国粮田氧化亚氮(N_(2)O)和甲烷(CH_(4))排放的影响,采用Meta分析方法,以粮食作物(小麦、玉米、水稻)主产区为研究对象,比较氮肥施用后不同气候条件、土壤基本理化性质、氮肥管理等因素对土壤N_(2)O、CH_(4)排放及全球增... 为探明氮肥对我国粮田氧化亚氮(N_(2)O)和甲烷(CH_(4))排放的影响,采用Meta分析方法,以粮食作物(小麦、玉米、水稻)主产区为研究对象,比较氮肥施用后不同气候条件、土壤基本理化性质、氮肥管理等因素对土壤N_(2)O、CH_(4)排放及全球增温潜势(GWP)和温室气体排放强度(GHGI)的影响。结果表明,相较于温带和亚热带气候区,在暖温带气候区施用氮肥后的土壤N_(2)O累积排放量、GWP和GHGI增幅最大。自然环境因素中,年均温对土壤N_(2)O累积排放量和GWP影响较大,年降雨量和年日照时数则分别对土壤CH_(4)累积排放量和GHGI影响较大。土壤全氮含量为0.9~1.5 g·kg^(-1)时的土壤N_(2)O累积排放量较高,>1.5 g·kg^(-1)时的CH_(4)累积排放量较高。N_(2)O、CH_(4)累积排放量及GWP和GHGI均在土壤有机质含量15~30 g·kg^(-1)时较高。土壤pH值增加促进温室气体排放。施氮量对土壤N_(2)O累积排放量有显著(P<0.05)正效应。氮肥基肥+追肥施用较一次性基施能有效减少气体排放,且氮肥+生物炭处理的GWP和GHGI增幅均低于秸秆还田和有机肥处理。施用缓控释氮肥比常规化肥产生更少的温室气体。综上所述,在我国种植主要粮食作物时,优化氮肥运筹,即基肥+追肥(基追比5∶5~0∶10,基肥<追肥)、氮肥+生物炭或施用缓控释氮肥均可较常规施用化肥氮有效减少土壤温室气体排放,降低排放强度。本研究结果对我国粮田氮肥的科学施用及温室气体减排具有重要意义。 展开更多
关键词 META分析 氮肥 氧化亚氮(N_(2)o) 甲烷(CH_(4)) 温室气体排放强度(GHGI)
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CuFe_2O_4/TiO_2复合光催化剂在模拟太阳光下对大肠杆菌杀灭作用的研究 被引量:2
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作者 张丽 黄可龙 +1 位作者 陈浩 阎建辉 《矿冶工程》 CAS CSCD 北大核心 2011年第2期101-105,共5页
采用溶胶-凝胶法制备了纳米CuFe2O4,然后与TiO2固相烧结成复合光催化剂,并通过TEM,XRD和UV-visDRS对复合光催化剂进行了表征,表明样品由粒径约为80 nm的粒子组成,晶体结构均匀。以大肠杆菌为研究对象,考察了复合光催化剂在模拟太阳光(15... 采用溶胶-凝胶法制备了纳米CuFe2O4,然后与TiO2固相烧结成复合光催化剂,并通过TEM,XRD和UV-visDRS对复合光催化剂进行了表征,表明样品由粒径约为80 nm的粒子组成,晶体结构均匀。以大肠杆菌为研究对象,考察了复合光催化剂在模拟太阳光(150 W氙灯,λ=200~900 nm)照射下的杀菌性能。结果表明:复合光催化剂比单一光催化剂杀菌效果好,在最佳条件下,模拟太阳光照射30 min后,CuFe2O4/TiO2复合光催化剂的杀菌率分别为单纯CuFe2O4和TiO2杀菌率的1.71倍和1.13倍。复合光催化剂杀菌性能受CuFe2O4与TiO2质量比及固相合成时焙烧温度的影响,当TiO2质量分数为80%、焙烧温度为600℃时,所制得的复合光催化剂处理大肠杆菌,在模拟太阳光照射30 min后,细菌的存活率仅为3.2%,而单纯CuFe2O4和TiO2光催化剂在最佳条件下杀菌30 min后细菌存活率分别为43.3%和14.2%。同样条件下在黑暗中使用催化剂或在光照下不用催化剂时细菌存活率分别为97.0%,93.2%。 展开更多
关键词 光催化剂 二氧化钛 大肠杆菌 cufe2o4/tio2 光催化杀菌
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Terpinen-4-ol suppresses proliferation and motility of cutaneoussquamous cell carcinoma cells by enhancing calpain-2 expression 被引量:1
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作者 DONGYUN RONG YUSHEN SU +3 位作者 ZHIRUI ZENG YAN YANG HONGUAN LU YU CAO 《Oncology Research》 2025年第3期605-616,共12页
Background:Terpinen-4-ol(T4O),a key constituent of tea tree essential oil and various aromatic plants,has shown promising antiproliferative and pro-apoptotic effects in melanoma and other cancer types.However,its effi... Background:Terpinen-4-ol(T4O),a key constituent of tea tree essential oil and various aromatic plants,has shown promising antiproliferative and pro-apoptotic effects in melanoma and other cancer types.However,its efficacy against cutaneous squamous cell carcinoma(cSCC)remains unclear.Thus,in this study,we investigated the in vivo and in vitro effects of T4O on cSCC cell lines and preliminarily explored its impacting pathways.Methods:Using CCK8 and assay colony formation,we assessed the viability of cSCC A431,SCL-1,and COLO-16 cells treated with T40 at varying concentrations(0,1,2,and 4μM).Flow cytometry was employed to evaluate T4O’s effect on cSCC cell’s cycle progression and apoptosis induction.Additionally,western blotting was utilized to examine the expression intensities of N-cadherin and E-cadherin,two indicative markers of the epithelial-mesenchymal transition(EMT)pathway.T4O’s in vivo effect on inhibiting tumor progression was evaluated on an established xenograft tumor model.Then,the molecular mechanisms of T4O’s antitumor effect were explored by an integrated genome-wide transcriptomics and proteomics study on cSCC A431c cells.Finally,calpain-2’s potential mediator role in T4O’s anti-tumor mechanism was investigated in calpain-2 knockdown cell lines prepared via siRNA transfection.Result:It’s demonstrated that T4O treatment inhibited cSCC proliferation,clonogenicity,migration,and invasion while inducing apoptosis and suppressing the EMT pathway.T4O administration also inhibited cSCC tumorigenesis in the xenograft tumor model.RNA-sequencing and iTRAQ analysis detected significant upregulation of calpain-2 expression in T4O-treated cSCC cells.Western blotting confirmed that T4O significantly increased calpain-2 expression and promoted proteolytic cleavage ofβ-catenin and caspase-12,two calpain-2 target proteins.Importantly,siRNA-mediated calpain-2 knockdown relieved T4O’s suppressive effect on cSCC cell proliferation and motility.Mechanistically,T4O upregulates calpain-2 expression and promotes the cleavage ofβ-catenin and caspase-12,with siRNA-mediated calpain-2 knockdown mitigating T4O’s suppressive effects.Conclusion:These findings suggest that T4O’s antitumor activity in cSCC is mediated through the upregulation of calpain-2 expression and subsequent modulation ofβ-catenin and caspase-12. 展开更多
关键词 Cutaneous squamous cell carcinoma(cSCC) Terpinen-4-ol(T4o) Calpain-2(CAPN2) Mouse xenograft Apoptosis
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Preparation of(NH_(4))_(2)V_(6)O_(16)·1.5H_(2)O nanoribbons and their application in aqueous ammonium-ion batteries
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作者 Lin XING Wei ZHOU +4 位作者 Kai-xiong XIANG Wei-na DENG Liang CHEN Hai ZHU Han CHEN 《Transactions of Nonferrous Metals Society of China》 2025年第4期1292-1305,共14页
To construct high-performance aqueous ammonium-ion full batteries,(NH_(4))_(2)V_(6)O_(16)·1.5H_(2)O(NVO)nanoribbon cathodes were prepared by pH-regulated hydrothermal synthesis.Anodes were prepared by growing the... To construct high-performance aqueous ammonium-ion full batteries,(NH_(4))_(2)V_(6)O_(16)·1.5H_(2)O(NVO)nanoribbon cathodes were prepared by pH-regulated hydrothermal synthesis.Anodes were prepared by growing the active material polyaniline(PANI)on carbon cloth.The assembled NVO//PANI full cells exhibit a reversible capacity of 109.5 mA·h/g at a current density of 1.0 A/g and a high energy density of 23 W·h/kg.The ammonium-ion intercalation/extraction mechanism is primarily governed by the pseudocapacitance behavior.These results indicate that NVO is a potential candidate as a cathode material for aqueous ammonium-ion batteries. 展开更多
关键词 (NH_(4))_(2)V_(6)o_(16)·1.5H_(2)o cathode ammonium-ion battery carbon cloth electrochemical performance
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Exceptional degradation of organic pollutant through piezoelectric photocatalysis and peroxymonosulfate activation in the designed Bi_(4)O_(5)Br_(2)/BCZT S-scheme heterojunction
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作者 Feng Huang Wen-Lin Wang +5 位作者 Gang Li Muhammad Humayun Qian Yu Yan Wang Chun-Dong Wang Jing Wang 《Rare Metals》 2025年第6期3981-3994,共14页
Peroxymonosulfate(PMS)is commonly used in advanced oxidation processes to degrade organic pollutants in wastewater.In this work,to obtain better PMS activation efficiency,Bi_(4)O_(5)Br_(2)/BCZT(BBT)piezoelectric photo... Peroxymonosulfate(PMS)is commonly used in advanced oxidation processes to degrade organic pollutants in wastewater.In this work,to obtain better PMS activation efficiency,Bi_(4)O_(5)Br_(2)/BCZT(BBT)piezoelectric photocatalyst was designed.Abundant active radicals produced by BBT under visible light irradiation and ultrasonic vibration were used to activate PMS,thereby achieving rapid degradation of high concentration pollutants.With the introduction of BCZT,the catalyst has a strong internal electric field and three-dimensional lamellar structure,which promotes the separation and transfer of electrons and holes.It is worth noting that under optimal reaction conditions,the degradation rate of ARB reached 93%by BBT15 within 10 min.The catalytic experiment combined with the piezoelectric performance test results revealed the key role of piezoelectric photocatalytic reaction in PMS activation.This provides an important prospect for PMS to effectively deal with the degradation of high concentrations of organic pollutants. 展开更多
关键词 Piezoelectric photocatalysis PMS Sscheme heterojunction Bi4o Br2 Internal electric field
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Synthesis of Porous MgAl_(2)O_(4)Fibers by Solid-state Reaction
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作者 WANG Xinyue XU Qing +4 位作者 ZHU Xinxin ZHOU Ruiqi DUAN Hongjuan ZHANG Haijun LI Shaoping 《China's Refractories》 2025年第4期26-30,共5页
Chemical vapor deposition is the predominant method to prepare MgAl_(2)O_(4)fibers.However,it faces several challenges,including exorbitantly high reaction temperatures,substantial production costs,and relatively low ... Chemical vapor deposition is the predominant method to prepare MgAl_(2)O_(4)fibers.However,it faces several challenges,including exorbitantly high reaction temperatures,substantial production costs,and relatively low yields.In this study,porous MgAl_(2)O_(4)fibers were fabricated through a solid-state reaction method,utilizing MgSO_(4)·5Mg(OH)_(2)·3H_(2)O whiskers as templates,mixed with either aluminum sol orα-Al_(2)O_(3)micropowder.The impact of various parameters on the synthesis of porous MgAl_(2)O_(4)fibres was systematically investigated,including the heat treatment temperature(1000,1100 and 1300℃),the holding time(3 and 10 h)and the aluminum source(aluminum sol orα-Al_(2)O_(3)micropowder).The results reveal that:(1)in comparison with fibers synthesized usingα-Al_(2)O_(3)as the aluminum source,those prepared with aluminum sol exhibit a significantly higher generation amount of MgAl_(2)O_(4);(2)as the heat treatment temperature increases,Al_(2)O_(3)gradually reacts with MgO,continuously increasing the formation amount of porous MgAl_(2)O_(4)with small and uniformly distributed nanopores,and the synthesized porous MgAl_(2)O_(4)fibres have small and uniform nanopores;(3)the optimal synthesis process involves using aluminum sol as the aluminum source and firing at 1300℃ for 3 h. 展开更多
关键词 MgSo_(4)·5Mg(oH)_(2)·3H_(2)o whiskers aluminum sol MgAl_(2)o_(4) porous fibers solid-state reaction method
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Mechanistic insights into sulfation-induced deactivation of CoMn_(2)O_(4)/CeTiO_(x) catalyst under low-temperature SCR conditions
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作者 Ning Luo Fengyu Gao +5 位作者 Chengzhi Wang Honghong Yi Shunzheng Zhao Yuansong Zhou Shangfeng Du Xiaolong Tang 《Chinese Journal of Catalysis》 2025年第10期70-86,共17页
The problem of water and sulfur poisoning in flue gas atmosphere remains a significant obstacle for low-temperature deNO_(x) catalysts.This study investigated the sulfation mechanism of the CoMn_(2)O_(4)/CeTiO_(x)(CMC... The problem of water and sulfur poisoning in flue gas atmosphere remains a significant obstacle for low-temperature deNO_(x) catalysts.This study investigated the sulfation mechanism of the CoMn_(2)O_(4)/CeTiO_(x)(CMCT)catalyst during the selective catalytic reduction of NO_(x) with NH3 under conditions containing H2O and SO_(2) at 150℃.Employing a comprehensive suite of time-resolved analysis and characterization techniques,the evolution of sulfate species was systematically categorized into three stages:initial rapid surface sulfate accumulation,the transformation of surface sulfates to bulk metal sulfates,and partial sulfates decomposition after the removal of H2O and SO_(2).These findings indicate that bulk metal sulfates irreversibly deactivate the catalyst by distorting active component lattices and consuming oxygen vacancies,whereas surface sulfates(including ammonium sulfates and surface-coordinated metal sulfates)cause reversible performance loss through decomposition.Furthermore,the competitive adsorption of H2O and SO_(2) significantly influences the catalytic efficiency,with H2O suppressing SO_(2) adsorption while simultaneously enhancing the formation of Brönsted acid sites.This research underscores the critical role of sulfate dynamics on catalyst performance,revealing the enhanced SO_(2) resistance of the Eley-Rideal mechanism facilitated by the Ce-Ti support relative to the Langmuir-Hinshelwood pathway.Collectively,the study unravels the complex interplay of sulfate dynamics influencing catalyst performance and provides potential approaches to mitigate deactivation in demanding atmospheric conditions. 展开更多
关键词 Selective catalytic reduction with NH3 CoMn_(2)o_(4)/Cetio_(x) H2o and So_(2)resistance Surface sulfate Bulk sulfate
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CuFe2O4@GO nanocomposite as an effective and recoverable catalyst of peroxymonosulfate activation for degradation of aqueous dye pollutants 被引量:11
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作者 Xiaoman Lei Menghan You +6 位作者 Fei Pan Min Liu Peng Yang Dongsheng Xia Qiang Li Yanting Wang Jie Fu 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第12期2216-2220,共5页
Recently,heterogeneous activation of peroxymonosulfate(PMS) to oxidatively degrade organic pollutants has been a hotspot.In the present work,copper ferrite-graphite oxide hybrid(CuFe2 O4@GO)was prepared and used as ca... Recently,heterogeneous activation of peroxymonosulfate(PMS) to oxidatively degrade organic pollutants has been a hotspot.In the present work,copper ferrite-graphite oxide hybrid(CuFe2 O4@GO)was prepared and used as catalyst to activate PMS for degradation of methylene blue(MB) in aqueous solution.A high degradation efficiency(93.3%) was achieved at the experimental conditions of20 mg/L MB,200 mg/L CuFe2 O4@GO,0.8 mmol/L PMS,and 25℃temperature.Moreover,CuFe2 O4@GO showed an excellent reusability and stability.The effects of various operational parameters including pollutant type,solution pH,catalyst dosage,PMS dosage,pollutant concentration,temperature,natural organic matter(NOM),and inorganic anions on the catalytic degradation process were comprehensively investigated and elucidated.The further mechanistic study revealed the Cu(Ⅱ)/Cu(Ⅰ) redox couple on CuFe2 O4@GO played the dominant role in PMS activation,where both hydroxyl and sulfate radicals were generated and proceeded the degradation of pollutants.In general,CuFe2 O4@GO is a promising heterocatalyst for PMS-based advanced oxidation processes(AOPs) in wastewater treatment. 展开更多
关键词 cufe2o4@Go PERoXYMoNoSULFATE Methylene blue Sulfate radical Advanced oxidation processes
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Comparing dark-and photo-Fenton-like degradation of emerging pollutant over photo-switchable Bi2WO6/CuFe2O4: Investigation on dominant reactive oxidation species 被引量:2
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作者 Jingjing Jiang Jiaying Gao +6 位作者 Shu Niu Xingyue Wang Tianren Li Shengda Liu Yanhong Lin Tengfeng Xie Shuangshi Dong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第8期147-160,共14页
The extensive use of tetracycline hydrochloride(TCH)poses a threat to human health and the aquatic environment.Here,magnetic p-n Bi2WO6/CuFe2O4 catalyst was fabricated to efficiently remove TCH.The obtained Bi2WO6/CuF... The extensive use of tetracycline hydrochloride(TCH)poses a threat to human health and the aquatic environment.Here,magnetic p-n Bi2WO6/CuFe2O4 catalyst was fabricated to efficiently remove TCH.The obtained Bi2WO6/CuFe2O4 exhibited 92.1%TCH degradation efficiency and 50.7%and 35.1%mineralization performance for TCH and raw secondary effluent from a wastewater treatment plant in a photo-Fenton-like system,respectively.The remarkable performance was attributed to the fact that photogenerated electrons accelerated the Fe(III)/Fe(II)and Cu(II)/Cu(I)conversion for the Fenton-like reaction between Fe(II)/Cu(I)and H2O2,thereby generating abundant·OH for pollutant oxidation.Various environmental factors including H2O2 concentration,initial pH,catalyst dosage,TCH concentration and inorganic ions were explored.The reactive oxidation species(ROS)quenching results and electron spin resonance(ESR)spectra confirmed that·O2-and·OH were responsible for the dark and photo-Fenton-like systems,respectively.The degradation mechanisms and pathways of TCH were proposed,and the toxicity of products was evaluated.This work contributes a highly efficient and environmentally friendly catalyst and provides a clear mechanistic explanation for the removal of antibiotic pollutants in environmental remediation. 展开更多
关键词 Magnetic Bi2Wo6/cufe2o4 Tetracycline hydrochloride DEGRADAtioN Reactive oxidation species Toxicity assessment
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基于中药超分子探究甘草配伍石膏与CaSO_(4)·2H_(2)O的汤剂相态、物质形态和晶型状态差异 被引量:4
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作者 张瑶芝 皮雯敏 +5 位作者 谭心如 徐冉 王旭 许明阳 黄雪梅 王鹏龙 《中国中药杂志》 北大核心 2025年第2期412-420,共9页
以甘草-石膏药对为研究对象,运用中药超分子化学研究矿物药石膏与其主要成分CaSO_(4)·2H_(2)O分别配伍植物药甘草的差异性,以初步探讨临床配伍应用石膏的科学内涵。采用马尔文粒度仪、扫描电子显微镜、电导率仪观察并测定石膏、CaS... 以甘草-石膏药对为研究对象,运用中药超分子化学研究矿物药石膏与其主要成分CaSO_(4)·2H_(2)O分别配伍植物药甘草的差异性,以初步探讨临床配伍应用石膏的科学内涵。采用马尔文粒度仪、扫描电子显微镜、电导率仪观察并测定石膏、CaSO_(4)·2H_(2)O及二者分别与甘草共煎后水煎液的微观形貌、粒径、电导率等物理指标;运用电感耦合等离子体发射光谱仪检测甘草-石膏、甘草-CaSO_(4)·2H_(2)O中的无机金属元素,采用等温滴定量热仪量化石膏、CaSO_(4)·2H_(2)O与甘草间的相互作用,利用傅里叶变换红外光谱仪分析甘草-石膏、甘草-CaSO_(4)·2H_(2)O的特征吸收峰变化,结合X-射线衍射仪测定2种配伍组合的晶体结构、物相组成;进一步以甘草酸代替甘草,分别与石膏、CaSO_(4)·2H_(2)O的药材/水煎液冻干粉进行共煎,以XRD结果进行验证分析。结果表明CaSO_(4)·2H_(2)O虽为石膏主要成分,但二者单煎液以及与甘草的共煎液存在明显不同,具体表现在:①CaSO_(4)·2H_(2)O与石膏药材的微观形貌均为无定形纤维状,但二者单煎液的粒径、电导率差异明显;②电镜下,甘草-CaSO_(4)·2H_(2)O的形貌不规则,甘草-石膏的形貌呈均匀纳米级颗粒;③甘草-CaSO_(4)·2H_(2)O、甘草-石膏的粒径和电导率等结果差别较大,且较单煎结果趋势不一致;④甘草-石膏较甘草-CaSO_(4)·2H_(2)O间的分子结合能力、官能团结构变化程度更强;⑤CaSO_(4)·2H_(2)O与石膏单煎液冻干粉的晶型差别明显,且二者与甘草共煎液的冻干粉晶型也明显不同。引起上述差异的原因是石膏具有较CaSO_(4)·2H_(2)O更丰富的微量元素,甘草酸代替甘草分别与石膏和CaSO_(4)·2H_(2)O的共煎物XRD结果进一步证明了石膏中微量元素对中药超分子形成的重要性,该研究初步揭示配伍矿物药石膏与CaSO_(4)·2H_(2)O对汤剂相态、物质形态和晶型状态的影响,为中医临床合理使用石膏提供依据。 展开更多
关键词 矿物药 石膏 甘草 CaSo_(42H_(2)o 微量元素 中药超分子
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TiSiW_(12)O_(40)/TiO_2催化合成肉桂酸系列酯 被引量:44
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作者 杨水金 余协卿 +1 位作者 梁永光 孙聚堂 《石油化工》 CAS CSCD 北大核心 2003年第3期230-233,共4页
以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,对以乙醇、正丙醇、正丁醇、正戊醇和肉桂酸为原料合成肉桂酸系列酯的反应条件进行了研究。实验表明,TiSiW12O40/TiO2是合成肉桂酸系列酯的良好催化剂,较系统地研究了醇酸摩尔比、催化剂用... 以固载杂多酸盐TiSiW12O40/TiO2为多相催化剂,对以乙醇、正丙醇、正丁醇、正戊醇和肉桂酸为原料合成肉桂酸系列酯的反应条件进行了研究。实验表明,TiSiW12O40/TiO2是合成肉桂酸系列酯的良好催化剂,较系统地研究了醇酸摩尔比、催化剂用量、反应时间诸因素对酯收率的影响。最佳反应条件为n(醇)/n(酸)=4/1或9/1,催化剂用量为反应物料总量的2 0%,反应时间为1 5~3 0h。上述条件下,肉桂酸乙酯的产率为58 7%,肉桂酸正丙酯的产率为62 0%,肉桂酸正丁酯的产率为81 2%,肉桂酸正戊酯的产率为93 3%。 展开更多
关键词 酯化反应 催化剂 TISIW12o40/tio2 催化合成 肉桂酸系列酯
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SO_4^(2-)/TiO_2-SiO_2固体超强酸的结构及其光催化性能 被引量:18
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作者 苏文悦 陈亦琳 +1 位作者 付贤智 魏可镁 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2002年第7期1398-1400,共3页
A series of SO 2- 4/TiO 2 SiO 2 catalysts with different mass fractions of SiO 2 were prepared by sol gel method. The effect of adding SiO 2 on the crystal structure, specific surface area, oxygen adsorption, and acid... A series of SO 2- 4/TiO 2 SiO 2 catalysts with different mass fractions of SiO 2 were prepared by sol gel method. The effect of adding SiO 2 on the crystal structure, specific surface area, oxygen adsorption, and acidity of SO 2- 4/TiO 2 catalyst and its photocatalytic property for degradation of bromomethane was studied. The results showed that the specific surface area and amount of oxygen adsorption of catalyst were increased by addition of SiO 2, leading to the obvious increase on photocatalytic activity of SO 2- 4/TiO 2 SiO 2 catalysts and mineralization ratio of bromomethane. Comparing with SO 2- 4/TiO 2, the acidic strength and anti moisture ability of SO 2- 4/TiO 2 SiO 2 catalyst were decreased. 展开更多
关键词 结构 光催化性能 固体超强酸 So4^2-/tio2-Sio2 二氧化钛 二氧化硅 硫酸
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磁性纳米TiO_2/SiO_2/Fe_3O_4光催化剂的制备及表征 被引量:43
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作者 廖振华 陈建军 +2 位作者 姚可夫 赵方辉 李荣先 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2004年第4期749-754,共6页
以纳米Fe3O4磁粉为核心,采用溶胶-凝胶法制备了TiO2/SiO2/Fe3O4复合光催化剂。用XRD、TEM及元素分析对其结构和表面形貌进行了表征。以具有偶氮染料结构的甲基橙水溶液为目标反应物,评价其光催化活性。结果表明,所制TiO2/SiO2/Fe3O4样... 以纳米Fe3O4磁粉为核心,采用溶胶-凝胶法制备了TiO2/SiO2/Fe3O4复合光催化剂。用XRD、TEM及元素分析对其结构和表面形貌进行了表征。以具有偶氮染料结构的甲基橙水溶液为目标反应物,评价其光催化活性。结果表明,所制TiO2/SiO2/Fe3O4样品为双层包覆型结构,SiO2为中间层,最外层是锐钛矿型的TiO2。该复合光催化剂对甲基橙溶液有较高的光催化活性,并具有可利用其磁性回收重用的特点,应用前景广泛。 展开更多
关键词 tio2/Sio2/Fe3o4 包覆 磁性 光催化
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TiSiW_(12)O_(40)/TiO_2催化合成氯乙酸异戊酯 被引量:17
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作者 杨水金 余协卿 +1 位作者 梁永光 朱贵军 《稀有金属》 EI CAS CSCD 北大核心 2002年第4期262-265,共4页
以固载杂多酸盐TiSiW12 O40 /TiO2 为多相催化剂 ,通过氯乙酸和异戊醇反应合成了氯乙酸异戊酯 ,并探讨了TiSiW12 O40 /TiO2 对酯化反应的催化活性 ,较系统地研究了醇酸物质的量比、催化剂用量、反应时间诸因素对产率的影响。实验表明 :T... 以固载杂多酸盐TiSiW12 O40 /TiO2 为多相催化剂 ,通过氯乙酸和异戊醇反应合成了氯乙酸异戊酯 ,并探讨了TiSiW12 O40 /TiO2 对酯化反应的催化活性 ,较系统地研究了醇酸物质的量比、催化剂用量、反应时间诸因素对产率的影响。实验表明 :TiSiW12 O40 /TiO2 具有良好的催化活性 ,醇酸物质的量比为 1.4∶1,催化剂用量为反应物料总量的 1.5 % ,反应时间 1.5h ,反应温度 98~ 12 6℃时 ,酯收率可达 92 .78%。 展开更多
关键词 TISIW12o40/tio2 氯乙酸异戊酯 催化 酯化反应
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TiSiW_(12)O_(40)/TiO_2催化合成乙酸异戊酯的研究 被引量:49
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作者 杨水金 肖继 梁永光 《化学试剂》 CAS CSCD 北大核心 2002年第2期107-108,121,共3页
以固载杂多酸盐 Ti Si W1 2 O4 0 /Ti O2 为多相催化剂 ,通过乙酸和异戊醇反应合成了乙酸异戊酯 ,并探讨了诸因素对产率的影响。结果表明 :Ti Si W1 2 O4 0 /Ti O2 具有良好的催化活性 ,醇酸摩尔比为 1.2∶ 1,催化剂用量为反应物料总量... 以固载杂多酸盐 Ti Si W1 2 O4 0 /Ti O2 为多相催化剂 ,通过乙酸和异戊醇反应合成了乙酸异戊酯 ,并探讨了诸因素对产率的影响。结果表明 :Ti Si W1 2 O4 0 /Ti O2 具有良好的催化活性 ,醇酸摩尔比为 1.2∶ 1,催化剂用量为反应物料总量的1.0 % ,反应时间 1.5 h,反应温度 110~ 12 2℃ ,产率可达 96 .3% 展开更多
关键词 TISIW12o40/tio2 催化合成 乙酸异戊酯 酯化反应 催化剂 因载杂多酸 二氧化钛
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SO_4^(2-4)/TiO_2固体超强酸催化合成冰片的研究 被引量:7
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作者 陈慧宗 刘显亮 +2 位作者 徐景士 刘永根 杨义文 《江西师范大学学报(自然科学版)》 CAS 2002年第4期363-365,共3页
研究了SO2-4/TiO2固体超强酸催化α-蒎烯酯化-皂化法合成冰片.冰片产率大于45%,正龙脑含量>97%,酯化反应条件:催化剂用量为α-蒎烯质量的1%,90~110℃,7h;皂化反应条件:80℃,3h.
关键词 合成 Α-蒎烯 So4^2-/tio2 固体超强酸催化剂 冰片 酯化-皂化法 龙脑 氯乙酸
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TiSiW_(12)O_(40)/TiO_2催化合成丙酸异戊酯 被引量:17
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作者 余新武 赖国松 +1 位作者 王建 孙丽 《化学研究与应用》 CAS CSCD 北大核心 2002年第4期423-424,445,共3页
Synthetic method of solid superacid TiSiW 12 O 40 /TiO 2 was described.The synthesis of iso amyl propionate catalyzed by TiSiW 12 O 40 /TiO 2 has been studied and the factors influencing on the yield is discussed.It s... Synthetic method of solid superacid TiSiW 12 O 40 /TiO 2 was described.The synthesis of iso amyl propionate catalyzed by TiSiW 12 O 40 /TiO 2 has been studied and the factors influencing on the yield is discussed.It shows that it’s an excellent catalyst,the yield of the iso amyl propionate can be over 77% when the molar ratio of iso amyl alcohol and propionic acid is 1.2,the quality of TiSiW 12 O 40 /TiO 2 is equal to 1.5% feed stock,the reaction time is 80min and the reaction temperature is about 103~107℃. 展开更多
关键词 TISIW12o40/tio2 催化合成 丙酸异戊酯 钨酸硅钛 二氧化钛 杂多酸盐 负载型催化剂
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SO_4^(2-)/TiO_2固体酸的红外和拉曼光谱研究 被引量:18
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作者 苏文悦 付贤智 魏可镁 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2000年第6期840-841,共2页
用IR、Raman光谱研究了SO2 -4 /TiO2 固体酸在不同烧结温度下的结构、晶相转变和表面酸中心。结果表明 ,SO2 -4 与TiO2 表面的结合为螯合式双配结构。当烧结温度小于 5 0 0℃时 ,SO2 -4 /TiO2 样品具有较高的结构稳定性 ,晶相结构以锐... 用IR、Raman光谱研究了SO2 -4 /TiO2 固体酸在不同烧结温度下的结构、晶相转变和表面酸中心。结果表明 ,SO2 -4 与TiO2 表面的结合为螯合式双配结构。当烧结温度小于 5 0 0℃时 ,SO2 -4 /TiO2 样品具有较高的结构稳定性 ,晶相结构以锐钛矿为主 ,表面B酸位数目约是L酸位数目的 2倍。当烧结温度大于5 0 0℃时 ,随着烧结温度的升高 ,表面结合的SO2 4 逐渐流失 ,晶相从锐钛矿转变为金红石 ,表面B酸位减少并消失。 展开更多
关键词 So^2-4/tio2固体酸 结构 催化剂 红外光谱
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磁性吸附材料CuFe_2O_4吸附砷的性能 被引量:35
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作者 武荣成 曲久辉 吴成强 《环境科学》 EI CAS CSCD 北大核心 2003年第5期60-64,共5页
根据Cu(Ⅱ )和Fe(Ⅲ )都对砷有较强的亲和性 ,制备了同时含有Cu(Ⅱ )和Fe(Ⅲ )的、可用磁分离方法进行分离回收的磁性吸附材料CuFe2 O4 ,并对其进行了表征及吸附砷的性能研究 .结果表明 ,该吸附剂对砷的吸附能力与溶液 pH有关 ,在弱酸... 根据Cu(Ⅱ )和Fe(Ⅲ )都对砷有较强的亲和性 ,制备了同时含有Cu(Ⅱ )和Fe(Ⅲ )的、可用磁分离方法进行分离回收的磁性吸附材料CuFe2 O4 ,并对其进行了表征及吸附砷的性能研究 .结果表明 ,该吸附剂对砷的吸附能力与溶液 pH有关 ,在弱酸性及中性条件下 ,吸附砷的能力最强 ,而对As(V)的吸附能力比对As(Ⅲ )更强些 ,在平衡浓度为 1 0 μg/L时 ,其吸附容量可达 1 0mg/ g左右 ,可以很容易地将水中浓度为 1~ 2 0mg/L的As(V)降到1 0 μg/L以下 .实验考察了几种无机阴离子对吸附砷的影响 ,表明较高浓度 (砷浓度的 2 0倍 )的硫酸盐对As(Ⅲ )和As(Ⅴ )的吸附均有一定影响 ,盐酸盐及磷酸盐则影响不明显 ;负载的As(V)可较容易地用 0 1mol/LNaOH洗脱下来 ,使吸附剂再生 ,而As(Ⅲ )则难以洗脱 ,这与 2种价态砷的吸附机理不同有关 . 展开更多
关键词 cufe2o4 磁性吸附剂 磁分离
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