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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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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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细胞分裂素信号调控植物雌配子体发育的研究进展
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作者 马苏卓 苏涵 +4 位作者 刘开创 黄幼梅 柴梦楠 秦源 蔡汉阳 《福建农林大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期153-158,共6页
雌配子体发育是被子植物有性生殖过程的重要阶段,它的顺利进行是保证植物完成整个生命周期的前提。细胞分裂素是植物自身合成的一类重要激素,广泛参与植物生长发育等一系列生命过程。在综述细胞分裂素代谢、信号感知和转导的基础上,重... 雌配子体发育是被子植物有性生殖过程的重要阶段,它的顺利进行是保证植物完成整个生命周期的前提。细胞分裂素是植物自身合成的一类重要激素,广泛参与植物生长发育等一系列生命过程。在综述细胞分裂素代谢、信号感知和转导的基础上,重点介绍细胞分裂素信号在植物雌配子体发育过程中的功能,旨在从细胞分裂素角度揭示植物雌性生殖发育机理,为提高农作物产量及其遗传改良研究提供理论依据。 展开更多
关键词 细胞分裂素信号 雌配子体发育 大孢子发生 雌配子体发生
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蕙兰雌雄配子和胚的发育
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作者 李亚敏 刘志雄 《东北林业大学学报》 CAS CSCD 北大核心 2024年第9期19-24,共6页
以蕙兰(Cymbidium faberi Rolfe)‘郑孝荷’和‘新极品’为试验材料,结合石蜡切片和植物显微技术对蕙兰雌雄配子体和胚的发育过程进行观察。结果表明:①蕙兰花药4室,小孢子母细胞减数分裂过程中的胞质分裂为连续型,小孢子四分体呈四面... 以蕙兰(Cymbidium faberi Rolfe)‘郑孝荷’和‘新极品’为试验材料,结合石蜡切片和植物显微技术对蕙兰雌雄配子体和胚的发育过程进行观察。结果表明:①蕙兰花药4室,小孢子母细胞减数分裂过程中的胞质分裂为连续型,小孢子四分体呈四面体型或左右对称型。小孢子四分体在同一个胼胝质内完成有丝分裂形成成熟的2-细胞型四合花粉。②蕙兰开花当天,仅部分胚珠珠心组织分化形成孢原细胞,授粉成功后才能刺激大孢子母细胞形成和胚囊的进一步发育,授粉60 d发育成8核7细胞成熟胚囊。蕙兰胚囊的发育类型属葱型(双孢型),倒生薄珠心胚珠,双层珠被。③受精后,蕙兰的合子通过橫向分裂形成基细胞和顶细胞,基细胞和顶细胞均参与了胚体的形成,至授粉96 d,胚发育成熟。蕙兰胚的发育类型属紫菀型,成熟的蕙兰种子无胚乳。 展开更多
关键词 蕙兰 小孢子发生 雄配子体发育 大孢子发生 雌配子体发育 胚的发育
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湖北黄精大小孢子发生及雌雄配子体发育
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作者 李华荣 周财 +3 位作者 魏薇 何夫 王业红 陈发菊 《西北植物学报》 CAS CSCD 北大核心 2024年第5期813-823,共11页
【目的】研究湖北黄精花部形态结构特征和大小孢子发生及雌雄配子体发育过程,以丰富黄精属植物的生殖生物学理论,为进一步开展湖北黄精的品种选育提供依据。【方法】以不同发育时期的湖北黄精花芽为试验材料,用显微观察法观察花部形态... 【目的】研究湖北黄精花部形态结构特征和大小孢子发生及雌雄配子体发育过程,以丰富黄精属植物的生殖生物学理论,为进一步开展湖北黄精的品种选育提供依据。【方法】以不同发育时期的湖北黄精花芽为试验材料,用显微观察法观察花部形态结构特征,石蜡切片技术对单花雌雄蕊进行切片观察。【结果】湖北黄精的花被为白色或淡黄绿色,花被筒近喉部稍缢缩;具6枚雄蕊,花丝下端与花被合生,花药开裂方式为纵裂;雌蕊子房上位,3心皮,花柱与子房等长。湖北黄精花药壁由4层细胞组成,成熟的绒毡层具多核,绒毡层发育类型为分泌型;小孢子母细胞减数分裂为连续型,四分体呈左右对称型排列,成熟花粉粒为2-细胞型;存在小孢子发育不同步的现象。雌蕊胚珠具双珠被、厚珠心;四分体呈直线型排列,胚囊发育类型为蓼型;存在双胚囊胚珠现象。在雄蕊的花药壁和雌蕊的子房壁都观察到有束状草酸钙针晶。【结论】湖北黄精雌雄蕊具有较原始的发育特征,虽然在发育过程中都存在异常现象,但雄蕊最终能形成正常的雄配子体,雌蕊低频率的双胚囊现象对总体受精结果影响很小。湖北黄精杂交育种可以选择花药开裂前一时期的花粉,花药壁和子房壁观察到的束状草酸钙针晶无法作为湖北黄精物种鉴定的依据。 展开更多
关键词 湖北黄精 大小孢子发生 雌雄配子体
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穴居植物湖南报春苣苔大小孢子发生及雌雄配子体发育研究
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作者 陈灵灵 李帅杰 +3 位作者 邹雅 吴尧晶 许海霞 蔡秀珍 《中国野生植物资源》 CSCD 2024年第4期39-44,共6页
目的:湖南报春苣苔(Primulina hunanensis)为我国特有的极具观赏价值的岩溶洞穴野生植物,具耐荫、耐贫瘠等特性,但其自然分布范围狭窄、野生种群规模小。胚胎发育是植物生活史中的关键环节,研究湖南报春苣苔的胚胎发育特征,为苦苣苔科(G... 目的:湖南报春苣苔(Primulina hunanensis)为我国特有的极具观赏价值的岩溶洞穴野生植物,具耐荫、耐贫瘠等特性,但其自然分布范围狭窄、野生种群规模小。胚胎发育是植物生活史中的关键环节,研究湖南报春苣苔的胚胎发育特征,为苦苣苔科(Gesneriaceae)植物的栽培育种提供新思路。方法:以湖南报春苣苔为材料,运用经典石蜡切片技术,对大、小孢子发生及雌、雄配子体发育过程进行解剖学观察。结果:湖南报春苣苔花药4室,花药壁由外到内依次为表皮、药室内壁、中层和腺质型绒毡层;小孢子母细胞减数分裂时的胞质分裂为同时型,四分体偶为交叉(十字)形,多为四面体形,花粉为二细胞型;倒生胚珠,单珠被,薄珠心,胚囊发育方式为蓼型。湖南报春苣苔花粉粒发育不同步,存在花粉败育、雌雄配子体异熟现象。结论:研究为报春苣苔属(Primulina)植物积累了基础的胚胎学资料,对于揭示苦苣苔科植物生殖机制及改良植物繁殖育种方式具有重要意义。 展开更多
关键词 湖南报春苣苔 大孢子发生 小孢子发生 雌配子体 雄配子体
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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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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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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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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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墨西哥落羽杉×落羽杉杂交的生殖与发育解剖学特征
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作者 王紫阳 熊豫武 +2 位作者 杨颖 殷云龙 於朝广 《林业科学》 EI CAS CSCD 北大核心 2023年第2期96-106,共11页
【目的】了解墨西哥落羽杉×落羽杉杂交的生殖与发育解剖学特征,为新品种、良种选育及种子发育的分子调控机制研究提供参考。【方法】通过形态观测和石蜡切片法,对杂交母本墨西哥落羽杉大孢子叶球从花芽分化至种子成熟的过程进行了... 【目的】了解墨西哥落羽杉×落羽杉杂交的生殖与发育解剖学特征,为新品种、良种选育及种子发育的分子调控机制研究提供参考。【方法】通过形态观测和石蜡切片法,对杂交母本墨西哥落羽杉大孢子叶球从花芽分化至种子成熟的过程进行了系统的形态学和解剖学观察。【结果】1—5月为大孢子发生和雌配子体发育期。大孢子母细胞减数分裂形成4个大孢子,其中合点端1个发育为功能大孢子,其余3个退化。墨西哥落羽杉的复合颈卵器由13~19个颈卵器组成,顶生,无腹沟细胞,复合颈卵器外侧具1层双核套层细胞。6月中旬为受精期,随着花粉管的生长,精原细胞体积不断增大,并在受精前分裂为2个同型精子,其中1个与卵细胞受精形成合子,精卵融合主要发生在颈卵器中上部。6月下旬—7月上旬为原胚发育期,7月中旬—8月上旬为早期胚发育期,8月中旬—9月中旬为后期胚发育期。墨西哥落羽杉原胚发育属于松杉类标准型,简单多胚和裂生多胚现象并存,胚发育不同步,成熟胚为直线型,具4~9枚子叶,胚轴中无髓。【结论】本研究首次从细胞学水平上观察了墨西哥落羽杉大孢子发生和雌配子体发育过程,探究了墨西哥落羽杉×落羽杉生殖融合和胚胎发育类型,为墨西哥落羽杉×落羽杉的种间杂交育种提供了生殖生物学依据。 展开更多
关键词 墨西哥落羽杉 落羽杉 大孢子发生 雌配子体发育 胚胎发育
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楸树大小孢子发生与雌雄配子体发育的研究 被引量:17
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作者 樊莉丽 彭方仁 +2 位作者 周琦 郝明灼 谭鹏鹏 《西北植物学报》 CAS CSCD 北大核心 2011年第3期431-438,共8页
运用石蜡切片法和整体透明法对楸树(Catalpa bungei C.A.Meyer)大、小孢子发生及雌、雄配子体发育过程进行了研究.结果表明:楸树可育雄蕊2枚,花药4室,药壁发育属双子叶型,腺质异型绒毡层.小孢子母细胞减数分裂为同时型,四分体后小孢子... 运用石蜡切片法和整体透明法对楸树(Catalpa bungei C.A.Meyer)大、小孢子发生及雌、雄配子体发育过程进行了研究.结果表明:楸树可育雄蕊2枚,花药4室,药壁发育属双子叶型,腺质异型绒毡层.小孢子母细胞减数分裂为同时型,四分体后小孢子不分离形成正四面体型四合花粉,偶有左右对称型和十字交叉型.成熟花粉为二细胞型,无萌发孔.子房上位,2室,中轴胎座,胚珠多数,倒生,单珠被,薄珠心,具珠被绒毡层.单孢原直接发育为大孢子母细胞,四分体线形排列,合点端大孢子发育为功能大孢子,胚囊发育为蓼型.雄蕊发育早于雌蕊,花开后雌、雄蕊趋于同熟.研究认为:虽然楸树雌、雄蕊发育过程中均存在一定比例的败育,但其花而不实"并非雄性或雌性不育所致.推测与其授粉受精和胚后发育有关. 展开更多
关键词 楸树 小孢子发生 大孢子发生 雄配子体 雌配子体
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观光木的大孢子发生与雌配子体形成 被引量:12
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作者 唐源江 叶秀麟 +1 位作者 曾庆文 刘玉壶 《热带亚热带植物学报》 CAS CSCD 北大核心 2003年第1期20-22,T002,共4页
对观光木(TsoongiodendronodorumChun)的大孢子发生、雌配子体形成过程的观察结果显示,观光木子房单心皮,心皮腹面壁上着生2-5个胚珠;胚珠倒生型,厚珠心,两层珠被;孢原细胞一个,并且自表皮下1-2层处分化。胚囊发育为蓼型。在四分体和成... 对观光木(TsoongiodendronodorumChun)的大孢子发生、雌配子体形成过程的观察结果显示,观光木子房单心皮,心皮腹面壁上着生2-5个胚珠;胚珠倒生型,厚珠心,两层珠被;孢原细胞一个,并且自表皮下1-2层处分化。胚囊发育为蓼型。在四分体和成熟胚囊时期观察到了异常发育现象。初步探讨了观光木濒危的生殖生物学原因。 展开更多
关键词 大孢子发生 雌配子体 木兰科 观光木
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柽柳大、小孢子发生和雌、雄配子体发育的观察 被引量:15
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作者 王仲礼 刘林德 方炎明 《植物研究》 CAS CSCD 北大核心 2005年第2期144-150,共7页
利用常规石蜡制片技术,对柽柳(Tamarix chinensis Lour.)的大、小孢子发生及雌、雄配子体发育过程进行了观察.主要结果如下:(1)花药壁由五层细胞组成,从外向内分别为表皮、药室内壁,两层中层和绒毡层.药壁的发育属于基本型.绒毡层为分泌... 利用常规石蜡制片技术,对柽柳(Tamarix chinensis Lour.)的大、小孢子发生及雌、雄配子体发育过程进行了观察.主要结果如下:(1)花药壁由五层细胞组成,从外向内分别为表皮、药室内壁,两层中层和绒毡层.药壁的发育属于基本型.绒毡层为分泌型.(2)孢原细胞为多孢原起源.小孢子母细胞减数分裂过程中的胞质分裂为连续型,形成的四分孢子为四面体型;同一药室的小孢子母细胞减数分裂几乎完全同步.(3)成熟花粉粒为2细胞型,具3个萌发孔.(4)柽柳为三心皮构成的单室复子房,每子房具有10~20个胚珠,基底胎座,胚珠为双珠被、厚珠心、倒生型.大孢子母细胞减数分裂形成1+3排列的4个大孢子,4个大孢子全部参与胚囊的形成.(5)胚囊发育为贝母型,反足细胞在胚囊成熟时充分发育.(6)同一朵花中,前期雄蕊的发育早于雌蕊的发育,后期当花粉成熟时,雌配子体也达到成熟,雌雄蕊发育趋于同步. 展开更多
关键词 小孢子发生 雄配子体发育 柽柳 小孢子母细胞 大孢子母细胞 减数分裂 制片技术 发育过程 细胞组成 胞质分裂 分裂过程 四分孢子 完全同步 胚囊发育 反足细胞 雌配子体 雄蕊发育 绒毡层 成熟 花药壁 基本型 分泌型 连续型
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烟草大小孢子发生和雌雄配子体发育研究 被引量:13
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作者 廖菊够 康洪梅 +3 位作者 代瑾然 姚恒 马文广 陈穗云 《西北植物学报》 CAS CSCD 北大核心 2013年第1期11-16,共6页
采用卡宝品红染色压片和石蜡切片法对迪勃纳氏烟草(Nicotiana debneyi)大小孢子发生和雌雄配子体发育过程进行了研究。结果发现:(1)迪勃纳氏烟草为两性花,其小孢子发生和雄配子体发育早于大孢子。(2)迪勃纳氏烟草小孢子发生和发育过程... 采用卡宝品红染色压片和石蜡切片法对迪勃纳氏烟草(Nicotiana debneyi)大小孢子发生和雌雄配子体发育过程进行了研究。结果发现:(1)迪勃纳氏烟草为两性花,其小孢子发生和雄配子体发育早于大孢子。(2)迪勃纳氏烟草小孢子发生和发育过程基本正常,减数分裂过程有少数细胞出现滞后染色体、染色体断片和染色体桥等异常现象;其胞质分裂为同时型,四分体为十字交叉型和正四面体型,成熟的花粉粒为2细胞型。(3)迪勃纳氏烟草为2室子房,中轴胎座,倒生胚珠,胚珠多数,胚囊发育为蓼型,大孢子发生和发育过程未观察到异常现象。 展开更多
关键词 迪勃纳氏烟草 大孢子发生 小孢子发生 雌配子体 雄配子体
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