期刊文献+
共找到131,811篇文章
< 1 2 250 >
每页显示 20 50 100
榴辉岩中传统地质温压计新解:来自PT视剖面图的证据 被引量:41
1
作者 魏春景 苏香丽 +1 位作者 娄玉行 李艳娟 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第9期2078-2088,共11页
石榴石-单斜辉石(GC)温度计和石榴石-单斜辉石-多硅白云母(GCP)压力计是确定榴辉岩形成温压条件的最常用方法,二者主要依据石榴石、绿辉石和多硅白云母中相组分之间的交换和转换变质反应。依据MORB成分计算的PT视剖面图表明,在不同榴辉... 石榴石-单斜辉石(GC)温度计和石榴石-单斜辉石-多硅白云母(GCP)压力计是确定榴辉岩形成温压条件的最常用方法,二者主要依据石榴石、绿辉石和多硅白云母中相组分之间的交换和转换变质反应。依据MORB成分计算的PT视剖面图表明,在不同榴辉岩矿物组合中,控制3个矿物相成分变化的相组分之间的变质反应不同。在低温含绿泥石、滑石和蓝闪石榴辉岩组合中,石榴石和绿辉石的镁含量主要受到含水矿物脱水反应的控制,并都随温度升高而升高,二者之间的铁镁交换反应并不起主要作用。因此,在自然界含有蓝闪石等含水矿物的低温榴辉岩中,由于绿辉石相对富镁而常常导致GC温度计结果偏低。在含有硬柱石的高压-超高压榴辉岩中,石榴石中的钙含量受到硬柱石的控制,随着压力升高或温度降低,硬柱石含量增加,使石榴石中钙降低,此时石榴石-绿辉石-多硅白云母之间的转换反应对石榴石成分的影响会很微弱,由于石榴石相对贫钙而导致GCP压力计结果偏低。在含有蓝晶石的中温高压-超高压榴辉岩中,矿物成分的变化受到石榴石-绿辉石之间的铁镁交换反应和石榴石-绿辉石-多硅白云母-蓝晶石-石英/柯石英之间的一系列转换反应控制,因此,GC和GCP温压计都能给出相对合理的结果。在低压普通角闪石榴辉岩中,石榴石和绿辉石中的镁含量主要反应压力变化,有时并不指示变质作用温度。在含有蓝闪石等含水矿物的低温榴辉岩中,Thermocalc程序中的平均温压(avPT)方法可以给出比较合适的温度,但压力结果与GCP压力计一样也会偏低一些。在蓝闪石和绿帘石等含水矿物消失后的中温蓝晶石榴辉岩中,avPT方法难以给出合理的PT信息。相对来说,视剖面图方法能够给出最多的PT信息,是目前确定变质岩PT条件的最好方法。 展开更多
关键词 超高压榴辉岩 地质温压计 剖面图 证据 conventional interpretation 石榴石 绿辉石 多硅白云母 含水矿物 反应 transfer exchange reactions results PT conditions 压力计 温度 蓝闪石 GCP 方法
下载PDF
Interfacial mechanisms of heterogeneous Fenton reactions catalyzed by iron-based materials: A review 被引量:39
2
作者 Jie He Xiaofang Yang +1 位作者 Bin Men Dongsheng Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第1期97-109,共13页
The heterogeneous Fenton reaction can generate highly reactive hydroxyl radicals(·OH)from reactions between recyclable solid catalysts and H2O2 at acidic or even circumneutral pH.Hence,it can effectively oxidiz... The heterogeneous Fenton reaction can generate highly reactive hydroxyl radicals(·OH)from reactions between recyclable solid catalysts and H2O2 at acidic or even circumneutral pH.Hence,it can effectively oxidize refractory organics in water or soils and has become a promising environmentally friendly treatment technology.Due to the complex reaction system,the mechanism behind heterogeneous Fenton reactions remains unresolved but fascinating,and is crucial for understanding Fenton chemistry and the development and application of efficient heterogeneous Fenton technologies.Iron-based materials usually possess high catalytic activity,low cost,negligible toxicity and easy recovery,and are a superior type of heterogeneous Fenton catalysts.Therefore,this article reviews the fundamental but important interfacial mechanisms of heterogeneous Fenton reactions catalyzed by iron-based materials..OH,hydroperoxyl radicals/superoxide anions(HO2./O2^-.)and high-valent iron are the three main types of reactive oxygen species(ROS),with different oxidation reactivity and selectivity.Based on the mechanisms of ROS generation,the interfacial mechanisms of heterogeneous Fenton systems can be classified as the homogeneous Fenton mechanism induced by surface-leached iron,the heterogeneous catalysis mechanism,and the heterogeneous reaction-induced homogeneous mechanism.Different heterogeneous Fenton systems catalyzed by characteristic iron-based materials are comprehensively reviewed.Finally,related future research directions are also suggested. 展开更多
关键词 Heterogeneous Fenton reactions ROS interfacial mechanisms iron-based materials
原文传递
Remimazolam benzenesulfonate anesthesia effectiveness in cardiac surgery patients under general anesthesia 被引量:32
3
作者 Fang Tang Jian-Min Yi +5 位作者 Hong-Yan Gong Zi-Yun Lu Jie Chen Bei Fang Chen Chen Zhi-Yi Liu 《World Journal of Clinical Cases》 SCIE 2021年第34期10595-10603,共9页
BACKGROUND Sedation with propofol injections is associated with a risk of addiction,but remimazolam benzenesulfonate is a comparable anesthetic with a short elimination half-life and independence from cell P450 enzyme... BACKGROUND Sedation with propofol injections is associated with a risk of addiction,but remimazolam benzenesulfonate is a comparable anesthetic with a short elimination half-life and independence from cell P450 enzyme metabolism.Compared to remimazolam,remimazolam benzenesulfonate has a faster effect,is more quickly metabolized,produces inactive metabolites and has weak drug interactions.Thus,remimazolam benzenesulfonate has good effectiveness and safety for diagnostic and operational sedation.AIM To investigate the clinical value of remimazolam benzenesulfonate in cardiac surgery patients under general anesthesia.METHODS A total of 80 patients who underwent surgery in the Department of Cardiothoracic Surgery from August 2020 to April 2021 were included in the study.Using a random number table,patients were divided into two anesthesia induction groups of 40 patients each:remimazolam(0.3 mg/kg remimazolam benzenesulfonate)and propofol(1.5 mg/kg propofol).Hemodynamic parameters,inflammatory stress response indices,respiratory function indices,perioperative indices and adverse reactions in the two groups were monitored over time for comparison.RESULTS At pre-anesthesia induction,the remimazolam and propofol groups did not differ regarding heart rate,mean arterial pressure,cardiac index or volume per wave index.After endotracheal intubation and when the sternum was cut off,mean arterial pressure and volume per wave index were significantly higher in the remimazolam group than in the propofol group(P<0.05).After endotracheal intubation,the oxygenation index and the respiratory index did not differ between the groups.After endotracheal intubation and when the sternum was cut off,the oxygenation index values were significantly higher in the remimazolam group than in the propofol group(P<0.05).Serum interleukin-6 and tumor necrosis factor-αlevels 12 h after surgery were significantly higher than before surgery in both groups(P<0.05).The observation indices were re-examined 2 h after surgery,and the epinephrine,cortisol 展开更多
关键词 ANESTHESIA Thoracic surgery Cardiac surgery Cardiopulmonary bypass HEMODYNAMICS PROPOFOL Drug-related side effects Adverse reactions
下载PDF
强化臭氧化在处理有机废水中的典型反应与应用 被引量:19
4
作者 曲久辉 《环境科学》 EI CAS CSSCI CSCD 北大核心 1997年第3期77-79,82,共4页
采用O3与其它物理化学过程联用的强化方法,可以显著提高臭氧化处理废水的功能与效率,降低臭氧消耗。
关键词 强化臭氧化 有机废水 处理 反应 应用 废水处理
下载PDF
Comparison of the effect and safety of Kuntai capsule and hormone replacement therapy in patients with perimenopausal syndrome:a systematic review and Meta-analysis 被引量:30
5
作者 Du Xiaoqin Xu Lin +4 位作者 Wang Lijun Heng Mingli Bu Huaien Hao Yu Tian Jinhui 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2017年第3期279-285,共7页
OBJECTIVE: To assess the effectiveness and safety of Kuntai capsule and hormone replacement therapy in treatment of perimenopausal syndrome.METHODS: Articles were retrieved from the databases Cochrane Database of Syst... OBJECTIVE: To assess the effectiveness and safety of Kuntai capsule and hormone replacement therapy in treatment of perimenopausal syndrome.METHODS: Articles were retrieved from the databases Cochrane Database of Systematic Reviews,Pub Med, Chinese National Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang Database. Only randomized controlled trials were included; 15 trials involving1243 patients were identified from January 2005 to April 2015. A systemic review and Meta-analysis of publications was performed. The review was limit-ed to randomized controlled trials that compared Kuntai capsule and hormone replacement therapy to treat perimenopausal syndrome for at least 3months. The primary outcome assessed was the treatment efficacy at 3 months, including effective rate of Kupperman menopausal scores, Kupperman menopausal scores, and blood estradiol(E2) or blood follicle stimulating hormone(FSH) levels.Other outcomes assessed were safety or adverse events, such as gastrointestinal complaints, breast distending pain, or vaginal bleeding.RESULTS: Kupperman menopausal scores showed no significant difference in effective rate [odds ratio(OR): 1.05, 95% confidence intervals(CI): 0.71 to1.55] and changes in FSH level [mean difference(MD): 2.14, 95% CI:-2.36 to 6.65]. There was a significant statistical difference in Kupperman menopausal scores(MD:-1.14, 95% CI:-2.03 to-0.25)and changes in E2level(MD:-16.41, 95% CI:-18.83to-13.69). There were fewer adverse events in the Kuntai capsule group than in the hormone replacement therapy group(OR: = 0.35, 95% CI: 0.25 to0.48, P < 0.01).CONCLUSION: Compared with hormone replacement therapy, Kuntai capsule can improve perimenopausal symptoms and blood E2 levels, and reduce the incidence of adverse events. 展开更多
关键词 Hormone replacement therapy Peri-menopause POSTMENOPAUSE Drug.related side ef-fects and adverse reactions Randomized con-trolled trial Review
原文传递
Kinetics in Mg-based hydrogen storage materials:Enhancement and mechanism 被引量:23
6
作者 Qun Luo Jianding Li +3 位作者 Bo Li Bin Liu Huaiyu Shao Qian Li 《Journal of Magnesium and Alloys》 SCIE EI CAS 2019年第1期58-71,共14页
Mg-based materials have been intensively studied for hydrogen storage applications due to their high energy density up to 2600 Wh/kg or 3700 Wh/L.However,the Mg-based materials with poor kinetics and the necessity for... Mg-based materials have been intensively studied for hydrogen storage applications due to their high energy density up to 2600 Wh/kg or 3700 Wh/L.However,the Mg-based materials with poor kinetics and the necessity for a high temperature to achieve 0.1 MPa hydrogen equilibrium pressure limit the applications in the onboard storage in Fuel cell vehicles(FCVs).Over the past decades,many methods have been applied to improve the hydriding/dehydriding(H/D)kinetics of Mg/MgH 2 by forming amorphous or nanosized particles,adding catalysts and employing external energy field,etc.However,which method is more effective and the intrinsic mechanism they work are widely differing versions.The hydrogenation and dehydrogenation behaviors of Mg-based alloys analyzing by kinetic models is an efficient way to reveal the H/D kinetic mechanism.However,some recently proposed models with physical meaning and simple analysis method are not known intimately by researchers.Therefore,this review focuses on the enhancement method of kinetics in Mg-based hydrogen storage materials and introduces the new kinetic models. 展开更多
关键词 Magnesium alloys Hydrogen storage materials Hydriding/dehydriding reactions KINETICS
下载PDF
Landscape of DILI-related adverse drug reaction in China Mainland 被引量:23
7
作者 Jiabo Wang Haibo Song +13 位作者 Feilin Ge Peng Xiong Jing Jing Tingting He Yuming Guo Zhuo Shi Chao Zhou Zixin Han Yanzhong Han Ming Niu Zhaofang Bai Guangbin Luo Chuanyong Shen Xiaohe Xiao 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2022年第12期4424-4431,共8页
Drug-induced liver injury(DILI)is a type of bizarre adverse drug reaction(ADR)damaging liver(L-ADR)which may lead to substantial hospitalizations and mortality.Due to the general low incidence,detection of L-ADR remai... Drug-induced liver injury(DILI)is a type of bizarre adverse drug reaction(ADR)damaging liver(L-ADR)which may lead to substantial hospitalizations and mortality.Due to the general low incidence,detection of L-ADR remains an unsolved public health challenge.Therefore,we used the data of 6.673 million of ADR reports from January 1st,2012 to December 31st,2016 in China National ADR Monitoring System to establish a new database of L-ADR reports for future investigation.Results showed that totally 114,357 ADR reports were retrieved by keywords searching of liver-related injuries from the original heterogeneous system.By cleaning and standardizing the data fields by the dictionary of synonyms and English translation,we resulted 94,593 ADR records reported to liver injury and then created a new database ready for computer mining.The reporting status of L-ADR showed a persistent 1.62-fold change over the past five years.The national population-adjusted reporting numbers of L-ADR manifested an upward trend with age increasing and more evident in men.The annual reporting rate of L-ADR in age group over 80 years old strikingly exceeded the annual DILI incidence rate in general population,despite known underreporting situation in spontaneous ADR reporting system.The percentage of herbal and traditional medicines(H/TM)L-ADR reports in the whole number was 4.5%,while 80.60%of the H/TM reports were new findings.There was great geographical disparity of reported agents,i.e.more cardiovascular and antineoplastic agents were reported in higher socio-demographic index(SDI)regions and more antimicrobials,especially antitubercular agents,were reported in lower SDI regions.In conclusion,this study presented a large-scale,unbiased,unified,and computer-minable L-ADR database for further investigation.Age-,sex-and SDI-related risks of L-ADR incidence warrant to emphasize the precise pharmacovigilance policies within China or other regions in the world. 展开更多
关键词 Adverse drug reactions Drug-induced liver injury Spontaneous reporting system Database Socio-demographic index PHARMACOEPIDEMIOLOGY PHARMACOVIGILANCE Geographical disparity
原文传递
An updated overview on the development of new photosensitizers for anticancer photodynamic therapy 被引量:23
8
作者 Juan Zhang Chengshi Jiang +3 位作者 Joao Paulo Figueiró Longo Ricardo Bentes Azevedo Hua Zhang Luis Alexandre Muehlmann 《Acta Pharmaceutica Sinica B》 SCIE CSCD 2018年第2期137-146,共10页
Photodynamic therapy(PDT), based on the photoactivation of photosensitizers(PSs), has become a well-studied therapy for cancer. Photofrin~?, belonging to the first generation of PS, is still widely used for the treatm... Photodynamic therapy(PDT), based on the photoactivation of photosensitizers(PSs), has become a well-studied therapy for cancer. Photofrin~?, belonging to the first generation of PS, is still widely used for the treatment of different kinds of cancers; however, it has several drawbacks that significantly limit its general clinical use. Consequently, there has been extensive research on the design of PS molecules with optimized pharmaceutical properties, with aiming of overcoming the disadvantages of traditional PS, such as poor chemical purity, long half-life, excessive accumulation into the skin, and low attenuation coefficients. The rational design of novel PS with desirable properties has attracted considerable research in the pharmaceutical field. This review presents an overview on the classical photosensitizers and the most significant recent advances in the development of PS with regard to their potential application in oncology. 展开更多
关键词 ANTI-CANCER PHOTOSENSITIZERS Photodynamic therapy Photochemical reactions ONCOLOGY BODIPY
原文传递
二茂铁酰基衍生物的研究进展 被引量:17
9
作者 时蕾 贾学顺 王玉炉 《合成化学》 CAS CSCD 1998年第2期137-149,共13页
综述了近年来二茂铁酰基衍生物如二茂铁甲醛、二茂铁酮和二茂铁甲酸的合成及反应的研究进展,简要介绍了它在生物学、医学和电化学等领域的应用。参考文献73篇。
关键词 二茂铁 酰基衍生物 合成 应用
下载PDF
聚糖-木质素钻井液处理剂作用效能评价 被引量:22
10
作者 陈刚 张洁 +1 位作者 张黎 杨乃旺 《油田化学》 CAS CSCD 北大核心 2011年第1期4-8,共5页
通过木质素磺酸钙LS与甲醛、伯/仲胺的Mannich反应制备了一系列木质素磺酸钙Mannich碱LM,再与杂聚糖SJ反应制备出系列聚糖-木质素SL。利用红外光谱对其进行结构表征,室内考察了SL作为钻井液处理剂对水基钻井液的黏度、切动力和滤失量等... 通过木质素磺酸钙LS与甲醛、伯/仲胺的Mannich反应制备了一系列木质素磺酸钙Mannich碱LM,再与杂聚糖SJ反应制备出系列聚糖-木质素SL。利用红外光谱对其进行结构表征,室内考察了SL作为钻井液处理剂对水基钻井液的黏度、切动力和滤失量等性能的影响。结果表明,常温下多数聚糖-木质素在水基钻井液中具有增黏作用和弱的降滤失作用,在高温热处理(180℃×24小时)后,对钻井液大多有一定的稀释作用,塑性黏度都比较适中,可明显改善塑性黏度和动塑比,且具有一定的降滤失作用。与基浆相比,SL水不溶物处理的钻井液的塑性黏度PV、切动力YP、表观黏度AV、静动力G均有所增加,但明显低于SL水溶物处理的钻井液的相应指标;与LS、SJ钻井液相比,SL水不溶物处理的钻井液,动塑比显著提高,滤失量小于SL水溶物处理的钻井液,降滤失性能优良,其中水不溶物SL1-2(合成原料中的胺为二甲胺)处理钻井液的降滤失性效果最好,高温处理后滤失量仅为12.7 mL。 展开更多
关键词 木质素 聚糖 反应 钻井液处理剂
下载PDF
Porous CuO nanowires as the anode of rechargeable Na-ion batteries 被引量:22
11
作者 Lijiang Wang Kai Zhang Zhe Hu Wenchao Duan Fangyi Cheng Jun Chen 《Nano Research》 SCIE EI CAS CSCD 2014年第2期199-208,共10页
We report the preparation of porous CuO nanowires that are composed of nanoparticles (-50 nm) via a simple decomposition of a Cu(OH)2 precursor and their application as the anode materials of rechargeable Na-ion b... We report the preparation of porous CuO nanowires that are composed of nanoparticles (-50 nm) via a simple decomposition of a Cu(OH)2 precursor and their application as the anode materials of rechargeable Na-ion batteries. The as-prepared porous CuO nanowires exhibit a Brunauer-Emmett-Teller (BET) surface area of 13.05 m^2.g^-1, which is six times larger than that of bulk CuO (2.16 m^2.g^-1). The anode of porous CuO nanowires showed discharge capacities of 640 mA.h.g^-1 in the first cycle and 303 mA.h.g^-1 after 50 cycles at 50 mA.g^-1 The high capacity is attributed to porous nanostructure which facilitates fast Na-intercalation kinetics. The mechanism of electrochemical Na-storage based on conversion reactions has been studied through cyclic voltammetry, X-ray diffraction (XRD), Raman spectroscopy, and high resolution transmission electron microscopy (HRTEM). It is demonstrated that in the discharge process, Na+ions first insert into CuO to form a CuⅡ1-x CuⅠ x O1-x/2solid and a Na2O matrix then CuⅡ1-xCu Ⅰ xO1-x/2 reacts with Na+ to produce Cu2O, and finally Cu2O decompose into Cu nanoparticles enclosed in a Na2O matrix. During the charge process, Cu nanopartides are first oxidized to generate Cu2O and then converted back to CuO. This result contributes to the design and mechanistic analysis of high-performance anodes for rechargeable Na-ion batteries. 展开更多
关键词 porous CuO nanowires anode materialelectrochemicalconversion reactions Na-ion batteries
原文传递
M@MIL-100(Fe) (M = Au, Pd, Pt) nanocomposites fabricated by a facile photodeposition process: Efficient visible-light photocatalysts for redox reactions in water 被引量:21
12
作者 Ruowen Liang Fenfen Jing Lijuan Shen Na Qin Ling Wu 《Nano Research》 SCIE EI CAS CSCD 2015年第10期3237-3249,共13页
Proper design and preparation of high-performance and stable dual functional photocatalytic materials remains a significant objective of research. In this work, highly dispersed noble-metal nanoparticles (Au, Pd, Pt... Proper design and preparation of high-performance and stable dual functional photocatalytic materials remains a significant objective of research. In this work, highly dispersed noble-metal nanoparticles (Au, Pd, Pt) were immobilized on MIL-100(Fe) (denoted M@MIL-100(Fe)) using a facile room-temperature photodeposition technique. The resulting M@MIL-100(Fe) (M = Au, Pd, and Pt) nanocomposites exhibited enhanced photoactivities toward photocatalytic degradation of methyl orange (MO) and reduction of heavy-metal Cr(VI) ions under visible-light irradiation (A ≥ 420 nm) compared with blank-MIL-100(Fe). Combining these results with photoelectrochemical analyses revealed that noble-metal deposition can effectively improve the charge-separation efficiency of MIL-100(Fe) under visible-light irradiation. This phenomenon in turn leads to the enhancement of visible-light-driven photoactivity of M@MIL-100(Fe) toward photocatalytic redox reactions. In particular, the Pt@MIL-100(Fe) with an average Pt particle size of 2 nm exhibited remarkably enhanced photoactivities compared with those of M@MIL-100(Fe) (M = Au and Pd), which can be attributed to the integrative effect of the enhanced light absorption intensity and more efficient separation of the photogenerated charge carrier. In addition, possible photocatalytic reaction mechanisms are also proposed. 展开更多
关键词 MIL-100(Fe) PHOTODEPOSITION noble metal redox reactions
原文传递
腐殖酸—金属离子反应动力学特征与稳态指标的探讨 被引量:17
13
作者 魏世强 李光林 +1 位作者 sterberg R 王定勇 《土壤学报》 CAS CSCD 北大核心 2003年第4期554-561,共8页
采用经改良的电位滴定法研究了腐殖酸与质子和钙离子反应的动力学特征 ,在恒温和连续通氩气保持严格无氧条件下 ,用标准酸将腐殖酸从中性滴定至pH2 6左右 ,在每一滴定点的反应动力学可分为快反应和慢反应两个阶段。各阶段体系的氧化还... 采用经改良的电位滴定法研究了腐殖酸与质子和钙离子反应的动力学特征 ,在恒温和连续通氩气保持严格无氧条件下 ,用标准酸将腐殖酸从中性滴定至pH2 6左右 ,在每一滴定点的反应动力学可分为快反应和慢反应两个阶段。各阶段体系的氧化还原电位 (ER)和玻璃电极电位 (EG)的变化可用松弛动力学方程Y =Y0 EXP(-t/τ)描述。在一定条件下 ,在慢反应阶段可观察到明显的震荡反应 ,表明腐殖酸体系为非平衡体系。腐殖酸与钙离子的反应是受扩散控制的慢反应过程。反应达到稳态后 ,ER 和EG 呈线形依托关系 ,其斜率ΔER/ΔpH(4 5 3± 1mV/pH)随腐殖酸和支持电解质不同变异甚小 ,可作为腐殖酸—金属离子反应的稳态指标。据此研究了腐殖酸的质子反应特征 ,获得了重现性很好的试验结果。表明供试腐殖酸存在HA、H2 A、H3A和HA2 四种类型配位基团 ,其表观解离常数 (pK)分别为 5 79~ 5 82、3 77~3 84、1 64~ 1 71和 2 75~ 2 79。 展开更多
关键词 腐殖酸-金属离子 反应动力学 特征特性 稳态指标 地球 生态环境 天然有机物
下载PDF
Fluorine-containing oxidizers for metal fuels in energetic formulations 被引量:19
14
作者 Siva Kumar Valluri Mirko Schoenitz Edward Dreizin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2019年第1期1-22,共22页
Fluorine containing oxidizers, primarily polymers, are extensively used in pyrotechnic compositions.Fluorinated oxidizers are less explored for metalized propellants and explosives despite a potential advantage of sub... Fluorine containing oxidizers, primarily polymers, are extensively used in pyrotechnic compositions.Fluorinated oxidizers are less explored for metalized propellants and explosives despite a potential advantage of substantial heat release combined with gaseous combustion products. This review summarizes different types of fluorinated oxidizers used in energetic formulations or of potential interest for such systems, including gases, polymers, and inorganic compounds. Types of energetic formulations employing metals and fluoropolymers are discussed in more detail, including methods used to prepare composites and resulting salient features of the obtained materials. Laboratory experiments characterizing such materials, in particular, electron microscopy and thermal analysis, are discussed, showing characteristic morphologies and reaction sequences observed in different metal-fluorinated oxidizer composites. Striking similarities are noted in reaction sequences for diverse compositions hinting at possible similarities in the respective reaction mechanisms. Experiments probing ignition and combustion of metal-fluorinated oxidizer composites in laboratory conditions are also reviewed, including impact, flash heating and shock ignition. Finally, some practical performance tests for energetic formulations are described following by a brief discussion of the reaction mechanisms expected to govern ignition and combustion in various metal-fluorinated oxidizer composites. The conclusions are combined with recommendation for future research in the area of reactive metal-fluorinated oxidizer composites. 展开更多
关键词 REACTIVE materials COMPOSITES Redox reactions PYROTECHNICS Propellants Explosives
下载PDF
Inflammatory response and neuronal necrosis in rats with cerebral ischemia 被引量:19
15
作者 Lingfeng Wu Kunnan Zhang +3 位作者 Guozhu Hu Haiyu Yang Chen Xie Xiaomu Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第19期1753-1762,共10页
In the middle cerebral artery occlusion model of ischemic injury, inflammation primarily occurs in the infarct and peripheral zones. In the ischemic zone, neurons undergo necrosis and apoptosis, and a large number of ... In the middle cerebral artery occlusion model of ischemic injury, inflammation primarily occurs in the infarct and peripheral zones. In the ischemic zone, neurons undergo necrosis and apoptosis, and a large number of reactive microglia are present. In the present study, we investigated the pathological changes in a rat model of middle cerebral artery occlusion. Neuronal necrosis appeared 12 hours after middle cerebral artery occlusion, and the peak of neuronal apoptosis ap- peared 4 to 6 days after middle cerebral artery occlusion. Inflammatory cytokines and microglia play a role in damage and repair after middle cerebral artery occlusion. Serum intercellular cell adhesion molecule-1 levels were positively correlated with the permeability of the blood-brain barrier. These findings indicate that intercellular cell adhesion molecule-1 may be involved in blood-brain barrier injury, microglial activation, and neuronal apoptosis. Inhibiting blood-brain barrier leakage may alleviate neuronal injury following ischemia, 展开更多
关键词 nerve regeneration middle cerebral artery occlusion inflammatory reactions intercellularcell adhesion molecule-I neurons blood-brain barrier MICROGLIA NSFC grant neural regeneration
下载PDF
Thermodynamics and kinetics of hydriding and dehydriding reactions in Mg-based hydrogen storage materials 被引量:20
16
作者 Qian Li Yangfan Lu +10 位作者 Qun Luo Xiaohua Yang Yan Yang Jun Tan Zhihua Dong Jie Dang Jianbo Li Yuan Chen Bin Jiang Shuhui Sun Fusheng Pan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2021年第6期1922-1941,共20页
Mg-based materials are one of the most promising hydrogen storage candidates due to their high hydrogen storage capacity,environmental benignity,and high Clarke number characteristics.However,the limited thermodynamic... Mg-based materials are one of the most promising hydrogen storage candidates due to their high hydrogen storage capacity,environmental benignity,and high Clarke number characteristics.However,the limited thermodynamics and kinetic properties pose major challenges for their engineering applications.Herein,we review the recent progress in improving their thermodynamics and kinetics,with an emphasis on the models and the influence of various parameters in the calculated models.Subsequently,the impact of alloying,composite,and nanocrystallization on both thermodynamics and dynamics are discussed in detail.In particular,the correlation between various modification strategies and the hydrogen capacity,dehydrogenation enthalpy and temperature,hydriding/dehydriding rates are summarized.In addition,the mechanism of hydrogen storage processes of Mg-based materials is discussed from the aspect of classical kinetic theories and microscope hydrogen transferring behavior.This review concludes with an outlook on the remaining challenge issues and prospects. 展开更多
关键词 Magnesium-based hydrogen storage materials Hydriding/dehydriding reactions THERMODYNAMICS Kinetic models Analysis methods
下载PDF
Aerosol effects on ozone concentrations in Beijing:A model sensitivity study 被引量:18
17
作者 Jun Xu Yuanhang Zhang +1 位作者 Shaoqing Zheng Youjiang He 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第4期645-656,共12页
Most previous O3 simulations were based only on gaseous phase photochemistry. However, some aerosol-related processes, namely, heterogeneous reactions occurring on the aerosol surface and photolysis rate alternated by... Most previous O3 simulations were based only on gaseous phase photochemistry. However, some aerosol-related processes, namely, heterogeneous reactions occurring on the aerosol surface and photolysis rate alternated by aerosol radiative influence, may affect O3 photochemistry under high aerosol loads. A three-dimensional air quality model, Models-3/Community Multi-scale Air Quality-Model of Aerosol Dynamics, Reaction, Ionization, and Dissolution, was employed to simulate the effects of the above-mentioned processes on O3 formation under typical high O3 episodes in Beijing during summer. Five heterogeneous reactions, i.e., NO2, NO3, N2O5, HO2, and O3, were individually investigated to elucidate their effects on O3 formation. The results showed that the heterogeneous reactions significantly affected O3 formation in the urban plume. NO2 heterogeneous reaction increased O3 to 90 ppb, while HO2 heterogeneous reaction decreased O3 to 33 ppb. In addition, O3 heterogeneous loss decreased O3 to 31 ppb. The effects of NO2, NO3, and N2O5 heterogeneous reactions showed opposite O3 concentration changes between the urban and extra-urban areas because of the response of the reactions to the two types of O3 formation regimes. When the aerosol radiative influence was included, the photolysis rate decreased and O3 decreased significantly to 73 ppbO3. The two aerosol-related processes should be considered in the study of O3 formation because high aerosol concentration is a ubiquitous phenomenon that affects the urbanand regional air quality in China. 展开更多
关键词 AEROSOL heterogeneous reactions OZONE radiative influence
原文传递
CO_(2) utilization: Developments in conversion processes 被引量:19
18
作者 Erdogan Alper Ozge Yuksel 《Petroleum》 2017年第1期109-126,共18页
Carbon dioxide capture,utilization and storage(CCUS)eincluding conversion to valuable chemicals-is a challenging contemporary issue having multi-facets.The prospect to utilize carbon dioxide(CO_(2))as a feedstock for ... Carbon dioxide capture,utilization and storage(CCUS)eincluding conversion to valuable chemicals-is a challenging contemporary issue having multi-facets.The prospect to utilize carbon dioxide(CO_(2))as a feedstock for synthetic applications in chemical and fuel industries-through carboxylation and reduction reactions-is the subject of this review.Current statute of the heterogeneously catalyzed hydrogenation,as well as the photocatalytic and electrocatalytic activations of conversion of CO_(2) to value-added chemicals is overviewed.Envisaging CO_(2) as a viable alternative to natural gas and oil as carbon resource for the chemical supply chain,three stages of development;namely,(i)existing mature technologies(such as urea production),(ii)emerging technologies(such as formic acid or other single carbon(C1)chemicals manufacture)and(iii)innovative explorations(such as electrocatalytic ethylene production)have been identified and highlighted.A unique aspect of this review is the exploitations of reactions of CO2 ewhich stems from existing petrochemical plants-with the commodity petrochemicals(such as,methanol,ethylene and ethylene oxide)produced at the same or nearby complex in order to obtain value-added products while contributing also to CO_(2) fixation simultaneously.Exemplifying worldwide ethylene oxide facilities,it is recognized that they produce about 3 million tons of CO2 annually.Such a CO_(2) resource,which is already separated in pure form as a requirement of the process,should best be converted to a value-added chemical there avoiding current practice of discharging to the atmosphere.The potential utilization of CO_(2),captured at power plants,should also been taken into consideration for sustainability.This CO_(2) source,which is potentially a raw material for the chemical industry,will be available at sufficient quality and at gigantic quantity upon realization of on-going tangible capture projects.Products resulting from carboxylation reactions are obvious conversions.In addition,provided that enough s 展开更多
关键词 Carbon capture and conversion CARBOXYLATION Catalysis C1-chemicals CO_(2)utilization COPOLYMERIZATION Dream reactions ELECTROCATALYSIS Photocatalysis Polymerization Reduction
原文传递
网箱养殖大黄鱼对颜色和光强的行为反应 被引量:16
19
作者 方金 宋利明 +2 位作者 蔡厚才 张禹 叶鹏 《上海水产大学学报》 CSCD 北大核心 2007年第3期269-274,共6页
2005年3月19日-2005年5月22日在浙江省平阳县南麂岛开发有限公司所属的南麂岛综合育苗场进行实地测量以及试验,通过用绿色、白色、红色、黄色、蓝色共5种颜色的光,并且以100 lx、200 lx、300 lx、400 lx、500 lx共5档照度作为刺激源,同... 2005年3月19日-2005年5月22日在浙江省平阳县南麂岛开发有限公司所属的南麂岛综合育苗场进行实地测量以及试验,通过用绿色、白色、红色、黄色、蓝色共5种颜色的光,并且以100 lx、200 lx、300 lx、400 lx、500 lx共5档照度作为刺激源,同时还用7种颜色的网片(黑色、蓝色、绿色、橙色、白色、青绿色、红色)作为刺激源,把实验水池按照离光源的不同距离共分为4个区域,观测大黄鱼对各种刺激的反应。结果表明:大黄鱼对于不同颜色网片的反应有极显著性差异(P<0.01),大黄鱼穿过蓝色网片、绿色网片的比例分别为64.97%、52.68%,比其它颜色网片的比例高。在对各颜色光及不同光源照度的反应实验中,5种颜色对大黄鱼的分布无显著性(P>0.05)影响,4个区域对大黄鱼的分布有极显著性(P<0.01)影响。大黄鱼趋于照度较高区域(0.5-500 lx)比趋于照度较低区域(0-0.5 lx)有显著性差异(P<0.05)。发现在照度较高的区域内,大黄鱼对光源照度为300 lx的蓝光或200 lx的绿光有一定的正趋向性。 展开更多
关键词 网箱养殖 大黄鱼 颜色 光强度 行为反应
下载PDF
Interfacial parasitic reactions of zinc anodes in zinc ion batteries:Underestimated corrosion and hydrogen evolution reactions and their suppression strategies 被引量:18
20
作者 Aruuhan Bayaguud Yanpeng Fu Changbao Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第1期246-262,I0007,共18页
Featured with high power density,improved safety and low-cost,rechargeable aqueous zinc-ion batteries(ZIBs) have been revived as possible candidates for sustainable energy storage systems in recent years.However,the c... Featured with high power density,improved safety and low-cost,rechargeable aqueous zinc-ion batteries(ZIBs) have been revived as possible candidates for sustainable energy storage systems in recent years.However,the challenges inherent in zinc(Zn) anode,namely dendrite formation and interfacial parasitic reactions,have greatly impeded their practical application.Whereas the critical issue of dendrite formation has attracted widespread concern,the parasitic reactions of Zn anodes with mildly acidic electrolytes have received very little attentions.Considering that the low Zn reversibility that stems from interfacial parasitic reactions is the major obstacle to the commercialization of ZIBs,thorough understanding of these side reactions and the development of correlative inhibition strategies are significant.Therefore,in this review,the brief fundamentals of corrosion and hydrogen evolution reactions at Zn surface is presented.In addition,recent advances and research efforts addressing detrimental side reactions are reviewed from the perspective of electrode design,electrode-electrolyte interfacial engineering and electrolyte modification.To facilitate the future researches on this aspect,perspectives and suggestions for relevant investigations are provided lastly. 展开更多
关键词 Zinc anodes Mildly acidic electrolytes Side reactions Coulombic efficiency Corrosions HER
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部