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Controllable preparation of particles with microfluidics 被引量:16
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作者 Guangsheng Luo Le Du Yujun Wang Yangcheng Lu Jianhong Xu 《Particuology》 SCIE EI CAS CSCD 2011年第6期545-558,共14页
This paper reviews recent development and achievements in controllable preparation of nanoparticles, micron spherical and non-spherical particles, using microfluidics. A variety of synthesis strategies are presented a... This paper reviews recent development and achievements in controllable preparation of nanoparticles, micron spherical and non-spherical particles, using microfluidics. A variety of synthesis strategies are presented and compared, including single-phase and multiphase microflows. The main structures of microfluidic devices and the fundamental principles of microflows for particle preparation are summarized and identified. The controllability of particle size, size distribution, crystal structure, morphology, physical and chemical properties, is examined in terms of the special features of microfluidic reactors. An outlook on opinions and predictions concerning the future development of powder technology with microfluidics is specially provided. 展开更多
关键词 Microfluidics Nanoparticles micron spherical particles micron non-spherical particles Preparation technology
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Transurethral dividing vaporesection for the treatment of large volume benign prostatic hyperplasia using 2 micron continuous wave laser 被引量:13
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作者 SUN Dong-chong YANG Yong WEI Zhi-tao HONG Bao-fa ZHANG Xu 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第17期2370-2374,共5页
Background The safety and efficiency of transurethral laser resection of the prostate to treat benign prostatic hyperplasia have been verified. However, this method does still not manage large volume prostates efficie... Background The safety and efficiency of transurethral laser resection of the prostate to treat benign prostatic hyperplasia have been verified. However, this method does still not manage large volume prostates efficiently. To tackle this problem, we have designed a method of "transurethral dividing vaporesection of prostate" using a 2 micron continuous wave laser. The aim of this study was to evaluate the safety and efficiency of this method in the management of large prostates (〉80 ml).Methods In this study, 45 cases of benign prostatic hyperplasia with a median prostatic volume of (123.7±26.7) ml (range, 80.2-159.8 ml) were treated by the same surgeon under epidural anesthesia. During the surgery, superapubic catheters were needed, and saline solution was used for irrigation. First, the prostate was divided longitudinally into several parts from the bladder neck to the prostatic apex, and then gradually incised transversely chip by chip. Intraoperative blood transfusion rate, postoperative complications, maximum urinary flow rate, International Prostate Symptom Score and quality of life scores were recorded for statistical analysis using SPSS 16.0 software.Results Intraoperatively, no transurethral resection syndrome was observed, and no blood transfusions were needed.The resected prostatic chips were easily flushed out of the bladder through the resectoscope sheath without the use of a morcellator. Median vaporesection time was (95.0±13.2) minutes (range, 75-120 minutes), and the median retrieved and removed prostatic tissue were (25.2±5.1) g (range, 15.5-34.7 g) and (75.4±16.4) g (range, 43.8-106.1 g), respectively. Median catheter time and hospital stay were (3.3±0.9) days (range, 3-5 days) and (4.8±1.8) days (range, 3-9 days), respectively. After a follow-up of 6 to 12 months, two patients had stress urinary incontinence and three had anterior urethral strictures. Satisfactory improvement was seen in maximum urinary flow rate, International Pro 展开更多
关键词 2 micron continuous wave laser VAPORESECTION benign prostatic hyperplasia
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微米/纳米雄黄微粒的制备及粒度测定 被引量:10
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作者 詹秀琴 郭立玮 +1 位作者 付廷明 袁红宇 《南京中医药大学学报》 CAS CSCD 2003年第1期24-25,共2页
目的 制备不同大小的雄黄颗粒并测定其粒径。方法 采用水飞、气流粉碎、细珠研磨和微射流 4种方法制备不同粒径的雄黄颗粒 ,并用激光粒度测试仪进行测定。结果 制得 4种微米、纳米级的雄黄颗粒。结论 通过采用新的制剂方法 ,可以得... 目的 制备不同大小的雄黄颗粒并测定其粒径。方法 采用水飞、气流粉碎、细珠研磨和微射流 4种方法制备不同粒径的雄黄颗粒 ,并用激光粒度测试仪进行测定。结果 制得 4种微米、纳米级的雄黄颗粒。结论 通过采用新的制剂方法 ,可以得到微米。 展开更多
关键词 制备 测定 雄黄 粒径 微米 纳米 中药
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微米、纳米SiC表面涂覆、改性的方法及研究现状 被引量:12
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作者 宿辉 曹茂盛 《电镀与精饰》 CAS 2005年第6期13-17,共5页
介绍了微米、纳米S iC表面涂覆、改性的实验方法,探讨了各种方法的特点。从微米、纳米S iC的三种不同形态入手,详细介绍了微米、纳米S iC的表面涂覆、改性的研究进展,并对微米、纳米S iC表面涂覆、改性技术给出了简要评价。
关键词 碳化硅 微米 纳米 涂覆 改性 化学镀
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无机分离膜及其在微米与亚微米级固液分离中的应用 被引量:14
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作者 赵宜江张艳 钟璟 徐南平 《现代化工》 CAS CSCD 2000年第1期22-26,共5页
无机膜分离装置过滤精度高,操作简便,占地面积小,在稀溶液的澄清过滤中有显著的优势,特别是无机膜优异的材料性能,使其在化学工业、石油化工、环保等行业的应用中具有独特优势。本文介绍了无机分离膜的特点、发展以及应用概况,对... 无机膜分离装置过滤精度高,操作简便,占地面积小,在稀溶液的澄清过滤中有显著的优势,特别是无机膜优异的材料性能,使其在化学工业、石油化工、环保等行业的应用中具有独特优势。本文介绍了无机分离膜的特点、发展以及应用概况,对无机分离膜在微米及亚微米级固液分离中的应用进行了概述。 展开更多
关键词 无机分离膜 微米 固液分离 膜分离 亚微米级
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植烟土壤物理特性及碳库对不同粒径生物质炭的动态响应 被引量:12
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作者 李佳轶 刘文 +6 位作者 任天宝 李亚森 王省伟 刘英杰 殷全玉 樊鹏飞 刘国顺 《中国土壤与肥料》 CAS CSCD 北大核心 2019年第2期14-23,共10页
为探究不同粒径生物炭对土壤物理化学特性以及土壤碳库的影响,在盆栽条件下,设置5个生物炭粒径施用水平:CK(不施生物炭)、T1(500~2 000μm)、T2(250~500μm)、T3(20~250μm)、T4(<20μm)。结果表明:(1)不同粒径生物炭均能显著降... 为探究不同粒径生物炭对土壤物理化学特性以及土壤碳库的影响,在盆栽条件下,设置5个生物炭粒径施用水平:CK(不施生物炭)、T1(500~2 000μm)、T2(250~500μm)、T3(20~250μm)、T4(<20μm)。结果表明:(1)不同粒径生物炭均能显著降低土壤容重,以T4降幅最大(4.13%)。(2)不同粒径生物炭均能显著提高田间持水量(WHC),提高幅度表现为T4>T3>T2>T1,但施生物炭处理间差异不显著。(3)施生物炭均能显著提升水稳性团聚体平均重量直径,以T4处理最高,但T4、T3、T2处理间差异不显著。(4)施用生物炭处理的土壤全碳、水溶性有机碳、易氧化态碳均显著高于CK,常规粒径生物炭在烤烟生育初期较不施生物炭显著增加了土壤微生物量碳(MBC)含量,后期则降低土壤MBC含量。小粒径生物炭较常规粒径生物炭T1在烤烟移栽45d后显著降低了土壤微生物量碳含量。(5)生物炭粒径越小,对土壤碳库管理指数的提升效果越好,T4对土壤碳库管理指数提升显著。综上所述,生物炭粒径越小对土壤容重、田间持水量及团粒结构的改良效果越优,同时,小粒径生物炭施用下土壤有机碳活性和碳库管理指数均优于常规粒径生物炭,更有利于提升地力和改善土壤质量。 展开更多
关键词 生物炭 粒径 微米 土壤物理 土壤碳库
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数控微米刨切试验台的设计与试验 被引量:11
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作者 张云鹤 刘烁 +2 位作者 马岩 杨春梅 刘旭东 《林产工业》 北大核心 2019年第1期30-34,共5页
为解决传统热磨法加工微米薄木片及木纤维中高能耗、工序复杂、加工成本高的缺点,现改变加工方法,采用顺纹纵向刨切木材的方式,研发了数控微米刨切试验台。试验台主要由机架、纵向进给机构总成、工件夹具、控制面板、刨切机构总成、升... 为解决传统热磨法加工微米薄木片及木纤维中高能耗、工序复杂、加工成本高的缺点,现改变加工方法,采用顺纹纵向刨切木材的方式,研发了数控微米刨切试验台。试验台主要由机架、纵向进给机构总成、工件夹具、控制面板、刨切机构总成、升降机构总成和限位机构组成,可对宽度为50 mm,长度为300~600 mm,高度为20~90 mm的木材工件进行纵向进给、切削量进给和刨切作业。笔者对试验台整机以及各机构进行设计,并通过ANSYSY对刀具进行强度校核。通过试验,确定刨切机构切削角δ取45°,刀刃伸出量h取0.05 mm,刀门宽度d取0.2 mm,刨得的木片平均厚度为18.7μm,最薄为15μm。最后通过显微镜观察发现经过刨切后的刀刃部分出现磨损,可通过表面改性提高刀具的耐磨性。 展开更多
关键词 刨切试验台 薄木片 微米 设计 试验
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Rapid degradation of hexachlorobenzene by micron Ag/Fe bimetal particles 被引量:9
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作者 Xiaoqin Nie Jianguo Liu +1 位作者 Xianwei Zeng Dongbei Yue 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第3期473-478,共6页
The feasibility of the rapid degradation of hexachlorobenzene (HCB) by micron-size silver (Ag)/iron (Fe) particles was investigated.Ag/Fe particles with different ratios (0,0.05%,0.09%,0.20%,and 0.45%) were pr... The feasibility of the rapid degradation of hexachlorobenzene (HCB) by micron-size silver (Ag)/iron (Fe) particles was investigated.Ag/Fe particles with different ratios (0,0.05%,0.09%,0.20%,and 0.45%) were prepared by electroless silver plating on 300 mesh Fe powder,and were used to degrade HCB at different pH values and temperatures.The dechlorination ability of Fe greatly increased with small Ag addition,whereas too much added Ag would cover the Fe surface and reduce the effective reaction surface,thereby decreasing the extent of dechlorination.The optimal Ag/Fe ratio was 0.09%.Tafel polarization curves showed that HCB was rapidly degraded at neutral or acidic pH,whereas low pH levels severely intensified H2 production,which consumed the reducing electrons needed for the HCB degradation.HCB degradation was more sensitive to temperature than pH.The rate constant of HCB dechlorination was 0.452 min-1 at 85℃,50 times higher than that at 31℃.HCB was degraded in a successive dechlorination pathway,yielding the main products 1,2,4,5-tetrachlorobenzene and 1,2,4-trichlorobenzene within 2 hr. 展开更多
关键词 dechlorination hexachlorobenzene silver-iron micron bimetallic particles chlorinated toxic organics
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高能混合炸药用铝粉的硅烷偶联剂表面改性研究 被引量:9
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作者 鲁彦玲 赵然 +1 位作者 高欣宝 杜仕国 《兵器装备工程学报》 CAS 2016年第6期57-60,共4页
为提高铝粉在混合炸药中的作用效能,用硅烷偶联剂对6μm铝粉分别与300 nm、50 nm两种纳米级粒径的铝粉级配混合试样进行了表面处理,对获得的粉体做了SEM、IR分析,结果表明:硅烷偶联剂在铝粉表面形成了一层硅烷偶联剂膜层,这层膜对单质... 为提高铝粉在混合炸药中的作用效能,用硅烷偶联剂对6μm铝粉分别与300 nm、50 nm两种纳米级粒径的铝粉级配混合试样进行了表面处理,对获得的粉体做了SEM、IR分析,结果表明:硅烷偶联剂在铝粉表面形成了一层硅烷偶联剂膜层,这层膜对单质铝氧化起保护作用,有利于保持活性铝含量,对提高铝粉在混合炸药中的作用具有积极的意义;微米级和纳米级铝粉混合并得到适当的表面处理,微米级颗粒可以作为纳米级颗粒良好分散的"载体",有效发挥纳米尺度颗粒的优势作用。 展开更多
关键词 铝粉 偶联剂 微米 纳米
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高Fe_3O_4含量微米尺寸磁性复合微球的合成及其在化学发光免疫检测中应用初探 被引量:5
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作者 徐雅雯 徐宏 +1 位作者 丁玮洁 古宏晨 《高分子学报》 SCIE CAS CSCD 北大核心 2010年第11期1340-1345,共6页
采用种子乳液聚合方法制得了微米尺度的高磁性物质含量的磁性复合微球.聚合体系中,以0.7~0.8μm的Fe3O4磁性聚集体细乳液作为种子,将苯乙烯,二乙烯基苯作为聚合单体加入到磁性聚集体细乳液中,对Fe3O4磁性聚集体进行溶胀后进行聚合.研... 采用种子乳液聚合方法制得了微米尺度的高磁性物质含量的磁性复合微球.聚合体系中,以0.7~0.8μm的Fe3O4磁性聚集体细乳液作为种子,将苯乙烯,二乙烯基苯作为聚合单体加入到磁性聚集体细乳液中,对Fe3O4磁性聚集体进行溶胀后进行聚合.研究了聚合过程中,溶胀时间对复合微球形貌和磁性物质含量的影响,获得系列形貌微球.通过透射电镜(TEM)、热重分析(TGA)、红外分析(FTIR)、振动样品磁强计(VSM)等表征手段对所制备的磁性聚合物微球进行分析表征.结果显示,所得到的磁性聚合物微球粒度为0.7~1μm,尺寸分布较均一,具有超顺磁性,磁性物质含量为29wt%~57wt%.然后又通过丙烯酸和苯乙烯共聚对微球表面羧基功能化后,得到了表面羧基密度为0.92mmol/g的微球,再将所制备的微球与生物分子偶联后(以hCG作为模式待检分子),在化学发光免疫检测上进行了初步的应用,取得到了较好的应用结果. 展开更多
关键词 磁性聚合物微球 高磁性物质含量 微米 羧基 形貌调控 生物应用
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微纳米级铁粉在水处理中的应用 被引量:7
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作者 罗驹华 张少明 《工业水处理》 CAS CSCD 北大核心 2008年第1期9-12,共4页
工业废水毒性强、难降解,既污染环境,又危害人体健康,其治理在全世界引起了强烈关注。微纳米级铁粉在水处理方面展现了优越的性能,具有广阔的应用前景。作者介绍了近年来微纳米级铁粉在不同水处理中的应用情况以及作用机理,并对其研究... 工业废水毒性强、难降解,既污染环境,又危害人体健康,其治理在全世界引起了强烈关注。微纳米级铁粉在水处理方面展现了优越的性能,具有广阔的应用前景。作者介绍了近年来微纳米级铁粉在不同水处理中的应用情况以及作用机理,并对其研究及应用前景做出了展望。 展开更多
关键词 铁粉 水处理 微米级 纳米级
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不同种类壳聚糖抗菌性能的比较 被引量:7
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作者 张惠珍 马国芳 +3 位作者 钱洪军 陈国伟 杨镪伟 刘俊杰 《河北师范大学学报(自然科学版)》 CAS 北大核心 2009年第1期74-77,共4页
采用固体培养基体外抑菌法,研究了市售壳聚糖、自制水溶性壳聚糖和微米化壳聚糖对大肠杆菌、枯草杆菌和变形杆菌生长的抑制作用.结果表明,改性产物的最低抑菌质量分数降低;水溶性壳聚糖对枯草杆菌的抑菌效果最佳,另2种壳聚糖对不同菌种... 采用固体培养基体外抑菌法,研究了市售壳聚糖、自制水溶性壳聚糖和微米化壳聚糖对大肠杆菌、枯草杆菌和变形杆菌生长的抑制作用.结果表明,改性产物的最低抑菌质量分数降低;水溶性壳聚糖对枯草杆菌的抑菌效果最佳,另2种壳聚糖对不同菌种的抑菌效果差别不大. 展开更多
关键词 水溶性壳聚糖 微米 细菌 抑菌活性
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3D direct writing and micro detonation of CL-20 based explosive ink containing O/W emulsion binder 被引量:6
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作者 Zhan-xiong Xie Chong-wei An +4 位作者 Bao-yun Ye Jia-qing Mu Chun-yan Li Min-jie Li Song-jin Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第8期1340-1348,共9页
The booming development of DIW technology present an unprecedented prospect in energetic materials field and has attracted great interest due to its relative simplicity and high flexibility of manufacturing.Herein,a n... The booming development of DIW technology present an unprecedented prospect in energetic materials field and has attracted great interest due to its relative simplicity and high flexibility of manufacturing.Herein,a novel CL-20 based explosive ink formulation have been developed successfully for MEMS initiation systems via DIW technology.We designed PVA/GAP into an oil-in-water(O/W)emulsion,in the way that the aqueous solution of PVA as water phase,the ethyl acetate solution of GAP as oil phase,the combination of Tween 80 and SDS as emulsifier,BPS as a curing agent of GAP.The ideal formulation with good shear-thinning rheology properties and clear gel point was prepared using only 10 wt%emulsion.The dual-cured network formed during the curing process made the printed sample have good mechanical properties.The printed samples had satisfactory molding effect without cracks or fractures,the crystal form of CL-20 not changed and the thermal stability have improved.Deposition of explosive inks via DIW in micro-scale grooves had excellent detonation performances,which critical detonation size was 1×0.045 mm,detonation velocity was 7129 m/s and when the corner reaching 150°can still detonated stably.This study may open new avenues for developing binder systems in explosive ink formulations. 展开更多
关键词 Direct writing Explosive ink Emulsion binder system CL-20 based energetic composites micron detonation
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Overdischarge-induced evolution of Cu dendrites and degradation of mechanical properties in lithium-ion batteries 被引量:3
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作者 Zixin Guo Siguo Yang +5 位作者 Wenyang Zhao Shenghui Wang Jiong Liu Zhichao Ma Hongwei Zhao Luquan Ren 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期497-506,I0014,共11页
The degradation of mechanical properties of overdischarge battery materials manifests as a significant effect on the energy density,safety,and cycle life of the batteries.However,establishing the correlation between d... The degradation of mechanical properties of overdischarge battery materials manifests as a significant effect on the energy density,safety,and cycle life of the batteries.However,establishing the correlation between depth of overdischarge and mechanical properties is still a significant challenge.Studying the correlation between depth of overdischarge and mechanical properties is of great significance to improving the energy density and the ability to resist abuse of the batteries.In this paper,the mechanical properties of the battery materials during the whole process of overdischarge from discharge to complete failure were studied.The effects of depth of overdischarge on the elastic modulus and hardness of the cathode of the battery,the tensile strength and the thermal shrinkage rate of the separator,and the performance of binder were investigated.The precipitation of Cu dendrites on the separator and cathode after dissolution of anode copper foil is a key factor affecting the performance of battery materials.The Cu dendrites attached to the cathode penetrate the separator,causing irreversible damage to the coating and base film of the separator,which leads to a sharp decline in the tensile strength,thermal shrinkage rate and other properties of the separator.In addition,the Cu dendrites wrapping the cathode active particles reduce the adhesion of the active particles binder.Meanwhile,the active particles are damaged,resulting in a significant decrease in the elastic modulus and hardness of the cathode. 展开更多
关键词 Overdischarge Cu dendrites Mechanical properties NANOINDENTATION micron scratch
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纳米材料的进步及应用
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作者 杨幼坤 徐军 +2 位作者 梁义田 梁蓓 俞小花 《铸造技术》 CAS 北大核心 2002年第6期397-399,共3页
简述国外和国内有关纳米材料的研究概况和所取得的成果 ,并分别介绍纳米磁性材料、纳米金属材料、纳米复合材料、纳米硬质合金材料及纳米航空材料等应用方面所取得的成果。
关键词 纳米材料 研究进展 磁性材料 金属材料 复合材料 航空材料 硬质合金
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不同温湿度条件下微米硼的氧化过程研究
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作者 何志成 吴建军 +7 位作者 杨述明 车碧轩 欧阳 李健 郑鹏 段炼 张宇 程玉强 《装备环境工程》 CAS 2024年第2期12-18,共7页
目的 探究不同温湿度条件下微米硼的氧化层结构特征。方法 利用高温水浴浸泡处理去除原料微米硼的表面氧化层,然后在恒温恒湿条件下对微米硼进行加速氧化,利用扫描电子显微镜、透射电子显微镜和X射线光电子能谱对加速氧化后硼颗粒的氧... 目的 探究不同温湿度条件下微米硼的氧化层结构特征。方法 利用高温水浴浸泡处理去除原料微米硼的表面氧化层,然后在恒温恒湿条件下对微米硼进行加速氧化,利用扫描电子显微镜、透射电子显微镜和X射线光电子能谱对加速氧化后硼颗粒的氧化层厚度及组成进行分析,总结表面氧化层结构及成分组成变化规律,揭示温湿度条件下微米硼的氧化机制。结果 微米硼经高温水浴浸泡处理后,表面氧化层去除率达到50%。随着加速氧化时间的延长,硼颗粒氧化层的厚度逐渐增大,由内向外硼颗粒表面可以用B-B_(x)O_(y)-B_(2)O_(3)三层结构来表示,B_(x)O_(y)总是伴随着B_(2)O_(3)同时出现的,且随着氧化反应的进行,颗粒表面B_(x)O_(y)的含量将超过B的含量。结论 不同温湿度条件下微米硼的氧化机制为O_(2)向B颗粒内部单向扩散的反应机制,B先与O_(2)反应,形成低氧化物B_(x)O_(y),B_(x)O_(y)进而与O_(2)反应生成B_(2)O_(3)。随着氧化层厚度的增加,O_(2)向B颗粒内部扩散的阻力增大,氧化反应速率随之降低。相比湿度的影响,温度的升高可显著加快硼表面氧化层的形成;温度一定时,湿度的增加可促进硼氧化层的形成。 展开更多
关键词 温度 湿度 微米 氧化层 推进剂 点火药
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微米级锂离子电池正极材料尖晶石LiMn_2O_4的合成及性能 被引量:4
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作者 吴晓梅 杨春生 +1 位作者 奚峻 吴益华 《复旦学报(自然科学版)》 CAS CSCD 北大核心 2004年第4期524-529,共6页
对微米级和常规固相反应方法制备的锂离子电池正极材料尖晶石LiMn2O4的结构和性能进行了比较,并采用扫描电子显微镜(SEM),X 射线衍射(XRD)及慢扫描循环伏安(SSCV)、交流阻抗(EIS)的电化学测试方法对材料进行了表征.结果表明微米级的尖晶... 对微米级和常规固相反应方法制备的锂离子电池正极材料尖晶石LiMn2O4的结构和性能进行了比较,并采用扫描电子显微镜(SEM),X 射线衍射(XRD)及慢扫描循环伏安(SSCV)、交流阻抗(EIS)的电化学测试方法对材料进行了表征.结果表明微米级的尖晶石LiMn2O4,颗粒均匀,晶体结晶性好;在10次慢扫描循环伏安曲线中,容量衰减相对较小;从材料的交流阻抗谱中可看出,随着循环的进行,靠近循环伏安峰电位附近的电荷转移电阻变化小. 展开更多
关键词 微米级锂离子电池 正极材料 尖晶石 LIMN2O4 合成 循环伏安
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Experimental Study on the Molten Salt at Micron Scale during the Melting Process
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作者 TIAN Ziqian LIAO Zhirong +3 位作者 XU Chao FANG Yongzhe JIANG Kaijun YUAN Mengdi 《Journal of Thermal Science》 SCIE EI CSCD 2024年第1期70-85,共16页
The investigation of the melting behaviors of the molten salt at micron scale during the melting process is critical for explaining the solid-liquid phase transition mechanism.In this paper,a novel experimental system... The investigation of the melting behaviors of the molten salt at micron scale during the melting process is critical for explaining the solid-liquid phase transition mechanism.In this paper,a novel experimental system and analysis method were proposed to study the melting process with three heating rates in the range of1-10℃/min of the solar salt at micron scale.The solid-liquid boundary morphology and phase transition kinetics of molten salt particles were focused on.Meanwhile,the correlations between liquid fraction,temperature and time under different heating rates were studied.The solid-liquid boundary morphology was depicted by the visualized experimental set-up,and the instantaneous liquid volume fraction during the non-isothermal phase transition was obtained.Then,the correlation between temperature and liquid volume fraction was proposed to reveal the evolution of the solid-liquid boundary with temperature at different heating rates.Furthermore,the non-isothermal phase transition kinetic equation was established by introducing a constant parameter(V_(a,b)),and more kinetic parameters such as 1g V_(a,b) and-lg V_(a,b)/b were studied.The results showed that the exponent b is not sensitive to the heating rate with a range of 3-5 for solar salt particles.However,the heating rate influences the value of V_(a,b) and presents a positive relationship.Besides,the non-isothermal phase transition kinetic equations at different heating rates in the range of 1-10℃/min can be quickly predicted by the proposed improved experimental test method.This study could fill the research insufficiency and provide significant guidance for future research on the solid-liquid transition mechanism of molten salts at micron scale. 展开更多
关键词 molten salt non-isothermal phase transition solid-liquid boundary morphology liquid volume fraction micron scale melting process
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Enhanced electrochemical performance of nanoscale single crystal NMC811 modification by coating LiNbO_(3)
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作者 Fengyu Zhang Yali Liang +6 位作者 Zhangran Ye Lei Deng Yunna Guo Ping Qiu Peng Jia Qiaobao Zhang Liqiang Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第5期514-518,共5页
Single crystallization is an important strategy to resolve intergranular cracks and unnecessary side reactions with electrolytes in layered transition metal oxide cathodes LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811).Due t... Single crystallization is an important strategy to resolve intergranular cracks and unnecessary side reactions with electrolytes in layered transition metal oxide cathodes LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811).Due to the limitations of high-temperature sintering and multi-step calcination,single crystal NMC811 generally shows irregular particles with a size of 2-3μm.However,the prolonged Li-ion diffusion pathway and the stress generated by the uneven de-/intercalation sluggish Li-ion diffusion kinetics,what is more,cause structural damage such as intragranular cracks.A slow Li extraction rate or particle size reduction will ameliorate the structural damage and improve the cycling stability.As the most promising cathodes for next-generation power batteries,NMC811 required fast charge performance and cycle stability.Particle size reduction appears to be the displacement option.Nanonization is an effective strategy to mitigate intragranular cracks of single crystal NMC811.However,the serious aggregation and increased specific surface area become new challenges.In this article,we synthesized monodisperse nanoscale single crystal NMC811 by molten salt method and modified the surface by LiNbO3 coating.The electrochemical performance shows that nanoscale single crystal NMC811 has faster kinetic and higher capacity retention,so the strategy of combining nanonization and surface coating is an alternative way to prepare high specific capacity and cycle stable single crystal NMC811. 展开更多
关键词 Ni-rich NMC811 Molten salt method Nanonization Surface coating micron cracks
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钻井液用抗高温阳离子乳化沥青的研制与性能评价 被引量:6
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作者 吴艳 王在明 +3 位作者 朱宽亮 李云峰 阚艳娜 李路宽 《断块油气田》 CAS 北大核心 2017年第5期719-722,共4页
针对冀东南堡中深层泥页岩地层微裂缝与层理发育、脆性强、易发生井壁失稳等问题,以阳离子乳化基质沥青、阳离子乳化特种沥青及耐高温弹性体乳液为原料,制备了一种抗高温阳离子乳化沥青封堵防塌剂。实验评价表明:抗高温阳离子乳化沥青... 针对冀东南堡中深层泥页岩地层微裂缝与层理发育、脆性强、易发生井壁失稳等问题,以阳离子乳化基质沥青、阳离子乳化特种沥青及耐高温弹性体乳液为原料,制备了一种抗高温阳离子乳化沥青封堵防塌剂。实验评价表明:抗高温阳离子乳化沥青能在井壁表面及裂缝内部吸附破乳,提升了泥饼质量,能使外泥饼光滑、致密,内泥饼有效封堵裂缝;与钻井液配伍性好,加量3%时,钻井液失水量减少47%,降滤失性较常用磺化沥青提高38%。抗高温阳离子乳化沥青可满足中深层高温、微米裂缝封堵需求。 展开更多
关键词 阳离子乳化沥青 封堵防塌剂 泥饼质量 降滤失 高温 微米
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