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Shugan Jieyu capsule effects on peripheral blood micro-124, micro- 132, and brain-derived neurotrophic factor in patients with mild to moderate depression
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作者 Xian Zhang Yang Liu +6 位作者 Hua-Fei Tang Feng Jiang Chun-Liang Chen Ting-Ting Wang Hui-Zhong Gu Qiang Zhao Rui Ma 《World Journal of Psychiatry》 SCIE 2024年第9期1354-1363,共10页
BACKGROUND To assess the effectiveness of Shugan Jieyu capsules on peripheral blood miR-124,miR-132,and brain-derived neurotrophic factor(BDNF)levels in patients with mild to moderate depression following coronary art... BACKGROUND To assess the effectiveness of Shugan Jieyu capsules on peripheral blood miR-124,miR-132,and brain-derived neurotrophic factor(BDNF)levels in patients with mild to moderate depression following coronary artery intervention[percuta-neous coronary intervention(PCI)]for coronary heart disease.Patients with mild-to-moderate depression of the liver-qi stagnation type after PCI for coronary heart disease at the 305th Hospital of the People’s Liberation Army were enrolled from June 2022 to November 2023 and randomly assigned to two groups:Experimental(treated with Shugan Jieyu capsules)and control(tr-eated with escitalopram oxalate tablets).This study compared the antidepressant effects of these treatments using 17-item Hamilton Rating Scale for Depression(HAMD-17)scores,metabolic equivalents,low-density lipoprotein cholesterol,BDNF,high-sensitivity C-reactive protein levels,miR-124 and miR-132 levels,distribution of immune-related lymphocyte subsets,and traditional Chinese me-dicine syndrome scores before and after 6 weeks of treatment.RESULTS No significant difference was observed in any index between the two groups before treatment(P>0.05).After treatment,the total efficacy rates were 93.33%and 90.00%in the experimental and control groups,respectively.Experimental group had significantly lower scores for the main and secondary syndromes compared to the control group(P<0.05).No significant difference was observed in the metabolic equivalents between the two groups be-fore and after treatment(P>0.05).The levels of low-density lipoprotein cholesterol,high-sensitivity C-reactive pro-tein,and miR-132 were significantly lower,whereas those of miR-124,BDNF,CD3+T lymphocytes,CD3+CD4+T helper lymphocytes,and CD3+CD4+/CD3+CD8+cells were significantly higher in the experimental group com-pared to the control group(P<0.05).The incidence of adverse reactions during experimental group was signi-ficantly lower than that in control group(P<0.05).CONCLUSION Shugan Jieyu capsules have good efficacy in patients with mild-to-moderate depression after PCI,and its me-chanism may contribute to the regulation of miR-124,miR-132,BDNF levels,and lymphoid immune cells. 展开更多
关键词 Shugan Jieyu capsule Coronary heart disease DEPRESSION Escitalopram oxalate tablet micro-124 micro-132 Brain-derived neurotrophic factor
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Impacts of Micro- and Nano-Plastics on Soil Properties and Plant Production in Agroecosystems: A Mini-Review
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作者 Dafeng Hui Faisal Hayat +1 位作者 Muhammad Salam Prabodh Illukpitiya 《Agricultural Sciences》 2024年第10期1089-1111,共23页
Micro- and nano-plastics (MNPs) are tiny plastic particles resulting from plastic product degradation. Soil MNPs have been identified as potential influential factors affecting various soil properties and crop biomass... Micro- and nano-plastics (MNPs) are tiny plastic particles resulting from plastic product degradation. Soil MNPs have been identified as potential influential factors affecting various soil properties and crop biomass productivity. This mini-review provides a synthesis of recent findings concerning their effects on soil physicochemical properties, microorganisms, organic carbon content, soil nutrients, greenhouse gas emissions, soil fauna, and their impacts on plant ecophysiology, growth, and production. The results indicate that MNPs may markedly impede soil aggregation ability, increase porosity, decrease soil bulk density, enhance water retention capacity, influence soil pH and electrical conductivity, and escalate soil water evaporation. Exposure to MNPs may predominantly induce changes in soil microbial composition, reducing the diversity and complexity of microbial communities and microbial activity while enhancing soil organic carbon stability, influencing soil nutrient dynamics, and stimulating organic carbon decomposition and denitrification processes, leading to elevated soil respiration and methane emissions, and potentially decreasing soil nitrous oxide emission. Additionally, MNPs may adversely affect soil fauna, diminish seed germination rates, promote plant root growth, yet impair plant photosynthetic efficacy and biomass productivity. These findings contribute to a better understanding of the impacts and mechanistic foundations of MNPs. Future research avenues are suggested to further explore the impacts and economic implications. 展开更多
关键词 Soil Property micro- and Nano-Plastics Crop Yield Soil Microorganism Soil Fauna Soil Greenhouse Gas Emissions
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Effect of Anion Surface Active Agent on the Preparation of SrTiO_3 Nano-Crystals 被引量:1
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作者 Qingli Ren Qiang Luo Quanxi Cao 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期603-604,共2页
SrTiO_3 nano-crystal samples with floccule or flake crystal morphology,which were indexed as a perovskite-type crystal structure based on the results of XRD and TEM,were successfully prepared by one-step liquid reacti... SrTiO_3 nano-crystal samples with floccule or flake crystal morphology,which were indexed as a perovskite-type crystal structure based on the results of XRD and TEM,were successfully prepared by one-step liquid reaction method.And the growth mechanism of the SrTiO_3 nano-crystals under the liquid condition with/without adding the surface active agent was investigated.It was found that adding the surface active agent contributes to the processing in which the ions gathering bodies transit to a more stable phase through the chemical reaction and form the flake SrTiO_3 nano-crystals. 展开更多
关键词 nano-crystals SRTIO3 anion surface active agent technology processing
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Up-conversion luminescence properties and energy transfer of Er^(3+)/Yb^(3+)co-doped oxyfluoride glass ceramic containing CaF_2 nano-crystals 被引量:1
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作者 马辰硕 焦清 +4 位作者 李龙基 周大成 杨正文 宋志国 邱建备 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第5期574-578,共5页
The Er^3+/yb^3+ co-doped transparent oxyfluoride glass-ceramics containing CaF2 nano-crystals were successfully prepared. After heat treatments, transmission electron microscopy (TEM) images showed that CaF2 nano-... The Er^3+/yb^3+ co-doped transparent oxyfluoride glass-ceramics containing CaF2 nano-crystals were successfully prepared. After heat treatments, transmission electron microscopy (TEM) images showed that CaF2 nano-crystals of 20-30 nm in diameter precipitated uniformly in the glass matrix. luminescence of Er^3+ at 540 nm and 658 nm was observed in Comparing with the host glass, high efficiency upconversion the glass ceramics under the excitation of 980 nm. Moreover, the size of the precipitated nano-crystals can be controlled by heat-treatment temperature and time. With the increase of the nano-crystal size, the intensity of the red emission increased more rapidly than that of the green emission. The energy transfer process of Er^3+ and Yb^3+ was convinced and the possible mechanism of Er^3+ up-conversion was discussed. 展开更多
关键词 nano-crystals up-conversion luminescence Er^3+/Yb^3+ co-doped glass ceramics
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Ultrafast Synthesis of Metal-Layered Hydroxides in a Dozen Seconds for High-Performance Aqueous Zn(Micro-)Battery 被引量:3
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作者 Xiangyang Li Fangshuai Chen +9 位作者 Bo Zhao Shaohua Zhang Xiaoyu Zheng Ying Wang Xuting Jin Chunlong Dai Jiaqi Wang Jing Xie Zhipan Zhang Yang Zhao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第3期16-31,共16页
Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly re... Efficient synthesis of transition metal hydroxides on conductive substrate is essential for enhancing their merits in industrialization of energy storage field.However,most of the synthetic routes at present mainly rely on traditional bottom-up method,which involves tedious steps,time-consuming treatments,or additional alkaline media,and is unfavorable for high-efficiency production.Herein,we present a facile,ultrafast and general avenue to synthesize transition metal hydroxides on carbon substrate within 13 s by Joule-heating method.With high reaction kinetics caused by the instantaneous high temperature,seven kinds of transition metal-layered hydroxides(TM-LDHs)are formed on carbon cloth.Therein,the fastest synthesis rate reaches~0.46 cm^(2)s^(-1).Density functional theory calculations further demonstrate the nucleation energy barriers and potential mechanism for the formation of metal-based hydroxides on carbon substrates.This efficient approach avoids the use of extra agents,multiple steps,and long production time and endows the LDHs@carbon cloth with outstanding flexibility and machinability,showing practical advantages in both common and micro-zinc ion-based energy storage devices.To prove its utility,as a cathode in rechargeable aqueous alkaline Zn(micro-)battery,the NiCo LDH@carbon cloth exhibits a high energy density,superior to most transition metal LDH materials reported so far. 展开更多
关键词 Ultrafast synthesis Thermal shock Metal-layered hydroxides Zn(micro-)battery
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In-situ hydrocarbon formation and accumulation mechanisms of micro- and nano-scale pore-fracture in Gulong shale, Songliao Basin, NE China 被引量:1
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作者 WANG Xiaojun CUI Baowen +5 位作者 FENG Zihui SHAO Hongmei HUO Qiuli ZHANG Bin GAO Bo ZENG Huasen 《Petroleum Exploration and Development》 SCIE 2023年第6期1269-1281,共13页
By conducting experimental analyses, including thermal pyrolysis, micro-/nano-CT, argon-ion polishing field emission scanning electron microscopy (FE-SEM), confocal laser scanning microscopy (CLSM), and two-dimensiona... By conducting experimental analyses, including thermal pyrolysis, micro-/nano-CT, argon-ion polishing field emission scanning electron microscopy (FE-SEM), confocal laser scanning microscopy (CLSM), and two-dimensional nuclear magnetic resonance (2D NMR), the Gulong shale oil in the Songliao Basin was investigated with respect to formation model, pore structure and accumulation mechanism. First, in the Gulong shale, there are a large number of pico-algae, nano-algae and dinoflagellates, which were formed in brackish water environment and constituted the hydrogen-rich oil source materials of shale. Second, most of the oil-generating materials of the Qingshankou Formation shale exist in the form of organo-clay complex. During organic matter thermal evolution, clay minerals had double effects of suppression and catalytic hydrogenation, which expanded shale oil window and increased light hydrocarbon yield. Third, the formation of storage space in the Gulong Shale was related to dissolution and hydrocarbon generation. With the diagenesis, micro-/nano-pores increased, pore diameter decreased and more bedding fractures appeared, which jointly gave rise to the unique reservoir with dual media (i.e. nano-scale pores and micro-scale bedding fractures) in the Gulong shale. Fourth, the micro-/nano-scale oil storage unit in the Gulong shale exhibits independent oil/gas occurrence phase, and shows that all-size pores contain oils, which occur in condensate state in micropores or in oil-gas two phase (or liquid) state in macropores/mesopores. The understanding about Gulong shale oil formation and accumulation mechanism has theoretical and practical significance for advancing continental shale oil exploration in China. 展开更多
关键词 micro- nano-scale oil storage unit hydrocarbon occurrence phase organo-clay complex in-situ hydrocarbon accumulation Gulong shale oil Cretaceous Qingshankou Formation Songliao Basin
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Fabrication and Characteristics of Nano-Floating Gate Memories with ZnO Nano-Crystals as Charge-Storage Layer
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作者 Lu Liu Yong Su +1 位作者 Jing-Ping Xu Yi-Xian Zhang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第6期102-105,共4页
Nano-floating gate memory devices with ZnO nano-crystals as charge storage layers are fabricated,and the influence of post-deposition annealing temperature and thickness of the ZnO layer are investigated.Atomic force ... Nano-floating gate memory devices with ZnO nano-crystals as charge storage layers are fabricated,and the influence of post-deposition annealing temperature and thickness of the ZnO layer are investigated.Atomic force microscopy and scanning electron microscopy reveal the morphology of discrete ZnO nano-crystals.For capacitance-voltage measurements,it is found that the memory device with 1.5 nm ZnO and annealed at 700℃shows a larger memory window of 4.3 V(at±6 V)and better retention characteristics than memoriy devices with2.5 nm ZnO or annealed at other temperatures.These results indicate that the nano-floating gate memory with ZnO nano-crystals can obtain good trade-off memory properties. 展开更多
关键词 ZNO Fabrication and Characteristics of Nano-Floating Gate Memories with ZnO nano-crystals as Charge-Storage Layer
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Storage Characteristics of Nano-Crystal Si Devices Using Different Measurements for MOS Capacitors
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作者 李蔚 张志刚 +3 位作者 梁仁荣 何洋 王柳笛 朱钧 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第8期1169-1172,共4页
The storage characteristics of nano-crystal Si (NC-Si) devices,especially for MOS capacitors,are studied by cross sectional transmission electron microscopy (TEM) and capacitance-voltage (C-V) measurement under ... The storage characteristics of nano-crystal Si (NC-Si) devices,especially for MOS capacitors,are studied by cross sectional transmission electron microscopy (TEM) and capacitance-voltage (C-V) measurement under different conditions,including programming and erasing at different temperatures and gate voltages,as well as using +/-bias-temperature (BT) measurements.Physical mechanisms such as carrier trapping,interface state filling,and temperature related deterioration are revealed.The experimental results demonstrate that the degradation of the program window and threshold voltage (VT) shift at high temperature,large voltage sweep range,and bias applied to sweep voltage is strongly related to the type of majority carriers. 展开更多
关键词 nano-crystAL STORAGE MEASUREMENT
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MICRO-Ⅱ网络数据采集方案 被引量:2
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作者 周海涛 许凤鸣 《烟草科技》 EI CAS 2002年第9期33-35,共3页
从工厂底层自动化及信息集成技术角度 ,详细介绍了GD公司MICRO Ⅱ控制系统的特点及其网络结构 ,提出了实现MICRO Ⅱ系统网络数据采集的 2种解决方案的可行性。通过对MICRO Ⅱ数据采集的实现 ,完全可以改变GDX1/X2包装机组目前的“信息... 从工厂底层自动化及信息集成技术角度 ,详细介绍了GD公司MICRO Ⅱ控制系统的特点及其网络结构 ,提出了实现MICRO Ⅱ系统网络数据采集的 2种解决方案的可行性。通过对MICRO Ⅱ数据采集的实现 ,完全可以改变GDX1/X2包装机组目前的“信息孤岛”状态。 展开更多
关键词 micro-Ⅱ系统 数据采集 卷烟厂 信息集成系统 网络结构
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Osteoblast Behavior on Hierarchical Micro-/Nano-Structured Titanium Surface 被引量:7
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作者 Weiyan Meng Yanmin Zhou Yanjing Zhang Qing Cai Liming Yang Jinghui Zhao Chunyan Li 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第3期234-241,共8页
In the present work, osteoblast behavior on a hierarchical micro-/nano-structured titanium surface was investigated. A hi- erarchical hybrid micro-/nano-structured titanium surface topography was produced via Electrol... In the present work, osteoblast behavior on a hierarchical micro-/nano-structured titanium surface was investigated. A hi- erarchical hybrid micro-/nano-structured titanium surface topography was produced via Electrolytic Etching (EE). MG-63 cells were cultured on disks for 2 h to 7 days. The osteoblast response to the hierarchical hybrid micro-/nano-structured titanium surface was evaluated through the osteoblast cell morphology, attachment and proliferation. For comparison, MG-63 cells were also cultured on Sandblasted and Acid-etched (SEA) as well as Machined (M) surfaces respectively. The results show signifi- cant differences in the adhesion rates and proliferation levels of MG-63 cells on EE, SLA, and M surfaces. Both adhesion rate and proliferation level on EE surface are higher than those on SLA and M surfaces. Therefore, we may expect that, comparing with SLA and M surfaces, bone growth on EE surface could be accelerated and bone formation could be promoted at an early stage, which could be applied in the clinical practices for immediate and early-stage loadings. 展开更多
关键词 dental implant OSTEOBLAST hierarchical micro-/nano-structure surface treatment electrolytic etching
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Macro-and Micro-Properties of Two Natural Marine Clays in China 被引量:6
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作者 蒋明镜 彭立才 +2 位作者 朱合华 林奕禧 黄良机 《China Ocean Engineering》 SCIE EI 2009年第2期329-344,共16页
In this paper,macro-and micro-properties of natural marine clay in two different and representative regions of China are investigated in detail.In addition to in-situ tests,soil samples are collected by use of Shelby ... In this paper,macro-and micro-properties of natural marine clay in two different and representative regions of China are investigated in detail.In addition to in-situ tests,soil samples are collected by use of Shelby tubes for laboratory examination in Shanghai and Zhuhai respectively,two coastal cities in China.In the laboratory tests,macro-properties such as consolidation characteristics and undrained shear strength are measured.Moreover,X-ray diffraction test,scanning electron microscope test,and mercury intrusion test are carried out for the investigation of their micro-properties including clay minerals and microstructure.The study shows that:(1)both clays are Holocene series formations,classified as either normal or underconsolidated soils.The initial gradient of the stress-strain curves shows their increase with increasing consolidation pressure;however,the Shanghai and the Zhuhai clays are both structural soils with the latter shown to be more structured than the former.As a result,the Zhuhai clay shows strain softening behavior at low confining pressures,but strain hardening at high pressures.In contrast,the Shanghai clay mainly manifests strain-hardening.(2)An activity ranges from 0.75 to 1.30 for the Shanghai marine clay and from 0.5 to 0.85 for the Zhuhai marine clay.The main clay mineral is illite in the Shanghai clay and kaolinite in the Zhuhai clay.The Zhuhai clay is mainly characterized by a flocculated structure,while the typical Shanghai clay shows a dispersed structure.The porous structure of the Shanghai clay is characterized mainly by large and medium-sized pores,while the Zhuhai clay porous structure is mainly featured by small and medium-sized pores.The differences in their macro-and micro-properties can be attributed to different sedimentation environments. 展开更多
关键词 marine clay macro- and micro- properties comparison MICROSTRUCTURE
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Modified Scherrer Equation to Estimate More Accurately Nano-Crystallite Size Using XRD 被引量:41
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作者 Ahmad Monshi Mohammad Reza Foroughi Mohammad Reza Monshi 《World Journal of Nano Science and Engineering》 2012年第3期154-160,共7页
Scherrer Equation, L=Kλ/β.cosθ, was developed in 1918, to calculate the nano crystallite size (L) by XRD radiation of wavelength λ (nm) from measuring full width at half maximum of peaks (β) in radian located at ... Scherrer Equation, L=Kλ/β.cosθ, was developed in 1918, to calculate the nano crystallite size (L) by XRD radiation of wavelength λ (nm) from measuring full width at half maximum of peaks (β) in radian located at any 2θ in the pattern. Shape factor of K can be 0.62 - 2.08 and is usually taken as about 0.89. But, if all of the peaks of a pattern are going to give a similar value of L, then β.cosθ must be identical. This means that for a typical 5nm crystallite size and λ Cukα1 = 0.15405 nm the peak at 2θ = 170° must be more than ten times wide with respect to the peak at 2θ = 10°, which is never observed. The purpose of modified Scherrer equation given in this paper is to provide a new approach to the kind of using Scherrer equation, so that a least squares technique can be applied to minimize the sources of errors. Modified Scherrer equation plots lnβ against ln(1/cosθ) and obtains the intercept of a least squares line regression, ln=Kλ/L, from which a single value of L is obtained through all of the available peaks. This novel technique is used for a natural Hydroxyapatite (HA) of bovine bone fired at 600°C, 700°C, 900°C and 1100°C from which nano crystallite sizes of 22.8, 35.5, 37.3 and 38.1 nm were respectively obtained and 900°C was selected for biomaterials purposes. These results show that modified Scherrer equation method is promising in nano materials applications and can distinguish between 37.3 and 38.1 nm by using the data from all of the available peaks. 展开更多
关键词 X-Ray DIFFRACTION nano-crystAL Scherrer EQUATION HYDROXYAPATITE
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Femtosecond Laser Thermal Accumulation-Triggered Micro-/Nanostructures with Patternable and Controllable Wettability Towards Liquid Manipulating 被引量:5
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作者 Kai Yin Lingxiao Wang +4 位作者 Qinwen Deng Qiaoqiao Huang Jie Jiang Guoqiang Li Jun He 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第6期206-218,共13页
Versatile liquid manipulating surfaces combining patternable and controllable wettability have recently motivated considerable attention owing to their significant advantages in droplet-solid impacting behaviors,micro... Versatile liquid manipulating surfaces combining patternable and controllable wettability have recently motivated considerable attention owing to their significant advantages in droplet-solid impacting behaviors,microdroplet self-removal,and liquid–liquid interface reaction applications.However,developing a facile and efficient method to fabricate these versatile surfaces remains an enormous challenge.In this paper,a strategy for the fabrication of liquid manipulating surfaces with patternable and controllable wettability on Polyimide(PI)film based on femtosecond laser thermal accumulation engineering is proposed.Because of its controllable micro-/nanostructures and chemical composition through adjusting the local thermal accumulation,the wettability of PI film can be tuned from superhydrophilicity(~3.6°)to superhydrophobicity(~151.6°).Furthermore,three diverse surfaces with patternable and heterogeneous wettability were constructed and various applications were successfully realized,including water transport,droplet arrays,and liquid wells.This work may provide a facile strategy for achieving patternable and controllable wettability efficiently and developing multifunctional liquid steering surfaces. 展开更多
关键词 WETTABILITY Femtosecond laser micro-/nanostructures Thermal accumulation Liquid manipulating
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Micro- and nanoporous materials capable of absorbing solvents and oils reversibly: the state of the art 被引量:5
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作者 Javier S. Acevedo Cortez Boris I. Kharisov +1 位作者 Thelma E. Serrano Quezada Tomas C. Hernandez Garcia 《Petroleum Science》 SCIE CAS CSCD 2017年第1期84-104,共21页
Treatment of petroleum spills and organic solvent pollution in general is an important issue; several techniques are under development to remove oil from water. The use of absorbents is one of the most common techniqu... Treatment of petroleum spills and organic solvent pollution in general is an important issue; several techniques are under development to remove oil from water. The use of absorbents is one of the most common techniques to tackle this problem. These absorbents can be classified based on their characteristics of recyclability into irreversible and reversible ones. In this review, we discuss the application of several materials as oil absorbents, according to their classification and characteristics such as hydrophobicity, surface area and oil absorption capacity. Also, the fabrication methods for some materials are presented and analyzed. 展开更多
关键词 Oil spills - Composites REVERSIBILITY Aerogels - Natural absorbents micro- and nanoporousmaterials
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A METHOD OF PREPARING SPHERICAL NANO-CRYSTAL CELLULOSE WITH MIXED CRYSTALLINE FORMS OF CELLULOSE Ⅰ AND Ⅱ 被引量:12
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作者 Xiao-fang Li En-yong Ding +1 位作者 Guo-kang Li Laboratory of Cellulose and Lignocellulosics Chemistry, Guangzhou Institute of Chemistry, Chinese Academy of Sciences, Guangzhou 510650 China College of Material Science and Engineering South China University of Technology, Guangzhou 510641, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2001年第3期291-296,共6页
A new kind of nano-crysta cellulose (NCC) prepared from natural cotton fiber has been obtained by the method ofacid hydrolysis. Compared to most other nanophase materials that derive from inorganic materials, our prod... A new kind of nano-crysta cellulose (NCC) prepared from natural cotton fiber has been obtained by the method ofacid hydrolysis. Compared to most other nanophase materials that derive from inorganic materials, our products are preparedfrom natural cotton fibers. The products are of spherical shape with mixed crystal forms of cellulose I and II. The preparationconditions determine the properties of the products. Prior treatment is a critical procedure. The properties of the products arealso strongly affected by such conditions as the kinds of acids used, the ratio of the acid mixture, the acid concentration, theultrasonic agitation time and hydrolysis temperature. The number average molecular weight of NCC is determined by gelpermeation chromatography (GPC). The particle size and shape were determined by transmission electron microscopy(TEM). X-ray diffraction was used to detect the crystallinity and average crystallite size of the panicle. 展开更多
关键词 Spherical nano-crystal cellulose Mixed crystal forms of cellulose and Ultrasonic agitation
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Krypton ion irradiation-induced amorphization and nano-crystal formation in pyrochlore Lu_2Ti_2O_7 at room temperature 被引量:1
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作者 谢秋荣 张建 +2 位作者 尹东明 郭奇勋 李宁 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期426-430,共5页
Polycrystalline pyrochlore Lu2Ti2O7 pellets are irradiated with 600-keV Kr^3+ions up to a fluence of 1.45 ×10^16Kr^3+/cm^2. Irradiation induced structural modifications are examined by using grazing incidence x... Polycrystalline pyrochlore Lu2Ti2O7 pellets are irradiated with 600-keV Kr^3+ions up to a fluence of 1.45 ×10^16Kr^3+/cm^2. Irradiation induced structural modifications are examined by using grazing incidence x-ray diffraction(GIXRD) and cross-sectional transmission electron microscopy(TEM). The GIXRD reveals that amorphous fraction increases with the increase of fluences up to 2 × 10^15Kr^3+/cm^2, and the results are explained with a direct-impact model.However, when the irradiation fluence is higher than 2 × 10^15Kr^3+/cm^2, the amorphous fraction reaches a saturation of-80%. Further TEM observations imply that nano-crystal is formed with a diameter of -10 nm within the irradiation layer at a fluence of 4 × 10^15Kr^3+/cm^2. No full amorphization is achieved even at the highest fluence of 1.45 × 10^16Kr^3+/cm^2(-36 displacement per atom). The high irradiation resistance of pyrochlore Lu2Ti2O7 at higher fluence is explained on the basis of enhanced radiation tolerance of nano-crystal structure. 展开更多
关键词 radiation damage amorphization nano-crystals ceramics
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Preparation and Mechanical Properties of Micro- and Nano-sized SiC/Fluoroelastomer Composites 被引量:1
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作者 率志君 刘志刚 +5 位作者 WANG Donghua ZHOU Pan LI Wanyou QIAO Yingjie LIU Ruiliang ZHOU Shi 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第4期658-663,共6页
Microand nano-sized SiC/fluoroelastomer (FKM) composites were prepared by a mechanical mixing method. These composites were first characterized by a rotorless rheometer. Then the effects of micro- and nano-sized SiC... Microand nano-sized SiC/fluoroelastomer (FKM) composites were prepared by a mechanical mixing method. These composites were first characterized by a rotorless rheometer. Then the effects of micro- and nano-sized SiC on hardness, static and dynamic mechanical properties of the composites were investigated. The increasing amount of the SiC filler increased the curing efficiency of the biphenyl curing system, which was evident from the rheometric properties of the resulting composites. The tensile properties of composite increased with the increasing of micro- and nano-sized SiC content. When the micro- and nano-sized SiC content was higher than 20 phr, the composites showed almost unchanged tensile properties. The increasing of the tensile property was mainly attributed to the well dispersed micro- and nano-sized SiC particles characterized by SEM images. Compared to pure FKM, the composites exhibited a higher glass transition temperature and lower tan peak value. 展开更多
关键词 fluoroelastomer (FKM) micro- and nano-sized SiC composites mechanical properties
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Characteristic Investigation of Nano-Crystal Hydrogen Storage Alloys
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作者 Xiao Fangming Huang Lili +3 位作者 Tang Renheng Lu Qiyun Peng Neng Wang Ying 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第z1期232-234,共3页
A Ml (NiCoMnA1)5 hydrogen storage alloys was prepared by double-roller rapid quenching.Its microstructure, electrochemically and kinetic characteristic were studied.A uniform crystal phase with CaCu5 structure could b... A Ml (NiCoMnA1)5 hydrogen storage alloys was prepared by double-roller rapid quenching.Its microstructure, electrochemically and kinetic characteristic were studied.A uniform crystal phase with CaCu5 structure could be detected by XRD analyses, whose average grain size is 30 ~ 50 nm and the ratio of c/a of nano-crystal hydrogen storage alloy is larger.The hydrogen absorption/desertion p - C isotherms of alloy show that its fiat-performance is perfect and the magnetic stagnant effect is very little.An simulate cell is used for electrochemical measurement.Electrode is 10C, the capacity decreasing rate via the 450 cycles at 7C is less than 20%. 展开更多
关键词 nano-crystAL hydrogen storage alloys electrochemically characteristic
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Micro-configuration Observation of Porous Bioceramic for Sliding on Intestinal Mucus Film
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作者 王欣宇 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第B12期210-213,共4页
The microstructure of the prepared porous bioceramic material, including surface porosity and apparent contact area with the artificial mucus film are computed and analyzed. The surface micro-configurations of the p... The microstructure of the prepared porous bioceramic material, including surface porosity and apparent contact area with the artificial mucus film are computed and analyzed. The surface micro-configurations of the porous material before and after sliding on the mucus film are observed in 2 D and 3 D by digital microsco py, We describe how much mucus enters and stays within different pares, and how the porous material with rough/ porous surface contacts with the mucus film ( elastic surfucel gel ) . The presented results illustrate that the material with different porous structure can lead to different mucus suction, surface scraping and changes of contact area and condition during sliding, which will be active for high friction of robotic endoscope with the intestinal wall for intestinal locomotion. 展开更多
关键词 micro- configuration SLIDING porous surface
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The Transmission Modes and Losses of the Poled Nano-crystal and Polymer Composite PbTiO_3 / PEK-c Thin-film Waveguides
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作者 任诠 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第1期66-69,共4页
Composite thin films of PbTiO3 nano-crystals and high transparency polymer polyetherketone (PEK-c) for application of non-linear optical devices were prepared by spin coating. The size of PbTiO3 nano-crystals was es... Composite thin films of PbTiO3 nano-crystals and high transparency polymer polyetherketone (PEK-c) for application of non-linear optical devices were prepared by spin coating. The size of PbTiO3 nano-crystals was estimated to be 30-40 nm using a transmission electron microscope. The refractive index and the mode propagation losses at 633 nm were measured using the prism coupling technique and improved photographic technique respectively. They were found to be 1.6545 and 2.00 dB cm^-1 (fundamental mode),respectively. Moreover, it is observed that this loss is increased at higher mode indices. 展开更多
关键词 optical properties nano-crystals thin-film waveguides mode propagation losses
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