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Effects of Tx-100-SDS on crystal growth of calcium carbonate in reverse microemulsion solution

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Chinese Science Bulletin 2007年第1期52卷 78-83页

作者： TANG Yu DU BiYing LI LinGang YANG Jun zhang yuanming Department of Chemistry Jinan University Guangzhou 510632 China

Syntheses of CaCO3 crystals in reverse microemulsion solutions containing 1-(1,1,3,3-tetramethylbu- tyl)-4-hydroxypolyethoxybenzene (Tx-100), sodium dodecyl sulfate (SDS) and their equimolar mixture were carried out at room temperature respectively. The crystal phase of CaCO3 is changed from calcite at low concentrations to vaterite at high concentrations of SDS and Tx-100. From rods at low concentration to olivary spheres at high concentration, SDS can influence the morphology of CaCO3 significantly, while almost no such effect for Tx-100. Hollow spheres, olivary spheres and even two fused olivary spheres of CaCO3 were produced at different concentrations of Tx-100-SDS, and the variation of crystal phase is opposite to that in the presence of SDS or Tx-100 alone. The effects of interaction of SDS with Tx-100 on morphology and crystal phase of CaCO3 were discussed. It was estimated to put forward that the formation of hollow CaCO3 crystals was caused by the collaborating actions of SDS template and TX-100 inhibition.

关键词：碳酸钙构造地貌学表面活性剂地理学

Progress in the study of algae and mosses in biological soil crusts

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Frontiers in Biology 2009年第2期4卷 143-150页

作者： Jiancheng ZHAO Yunpu ZHENG Bingchang zhang Ying CHEN yuanming zhang College of Life Science Hebei Normal UniversityShijiazhuang 050016China Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumuqi 830011China Graduate School of Chinese Academy of Sciences Beijing 100049China College of Biological Science and Engineering Hebei University of Economics and BusinessShijiazhuang 050061China

Algae and mosses are not only two of the familiar communities in the process of desert vegetational succession,but also have the highest biomass in biological soil ***,being the pioneer plants,algae and mosses are involved in the establishment of biological soil crusts,which have great importance in arid environments and play a major role in desert ecosystems,such as being the indicator of the vegetation type,soil-holding,preventing erosion by water and wind,and sand *** paper reviews the advances in the study of algae and mosses in arid and semi-arid *** mainly describes the ecological functions of algae and mosses including their influences on water cycle,circulation of substances,and community *** addition,the relationships between algae and mosses are ***,some suggestions are proposed for the research orientations of algae and mosses in biological soil ***,algae and mosses have significant ecological importance in arid areas,especially in those areas where environmental problems are becoming increasingly serious.

关键词： algae biological soil crusts mosses

Temporal-spatial dynamics of distribution patterns of microorganism relating to biological soil crusts in the Gurbantunggut Desert

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Chinese Science Bulletin 2006年第A1期51卷 124-131页

作者： WU Nan WANG Hongling LIANG Shaoming NIE Huali zhang yuanming Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

生物土壤外壳用作贡献沙固定的一个重要生物因素。这研究被进行在关于地点的外壳中调查微生物的时间空间的可变性，沙沙丘和季节的土壤层。在苔藓主导的内部沙丘的区域，更高的土壤营养素和水集中是可能的维持微生物引起的活动。细菌显... 详细信息

生物土壤外壳用作贡献沙固定的一个重要生物因素。这研究被进行在关于地点的外壳中调查微生物的时间空间的可变性，沙沙丘和季节的土壤层。在苔藓主导的内部沙丘的区域，更高的土壤营养素和水集中是可能的维持微生物引起的活动。细菌显示出解决和生长的最高的能力在在春天和秋天内部沙丘。土壤水内容在内部沙丘的区域在土壤外壳中到达了最高的价值，特别在春天。放线菌和真菌的数量的变化基本上在沙沙丘的不同地点显示出一致趋势。与加深土壤层，因为环境因素在春天和秋天波动，每个微生物组的数量的垂直分发显示出不同特征。在不同微生物组之中，细菌是占优势的，在在所有的春天和秋天的放线菌下一个和真菌最少玷污层(020 厘米) 。细菌和土壤水内容的比例比在在所有土壤层(020 厘米) 的秋天的那些在春天是更高的。没有一致趋势在放线菌和真菌被发现。结果证明微生物的数量是显著地积极的与有机物内容相关，土壤水满意的、全部的 N，全部的 P，可得到的 P，可得到的 K， pH，电的传导性，全部的盐内容，过氧化氢酶， urease，磷酸酶和碱的磷酸酶。

关键词：时-空动力学分配结构土壤微生物 Gurbantunggut沙漠

NCPAP序贯高流量鼻导管湿化氧疗治疗新生儿肺炎合并呼吸衰竭效果

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中国计划生育学杂志 2024年第3期32卷 563-567,572页

作者：张元铭梁玉兰杨盛泉四川省泸州市人民医院 646000

目的:探究经鼻持续气道正压通气(NCPAP)序贯高流量鼻导管湿化氧疗(HHFNC)治疗新生儿肺炎合并呼吸衰竭(RF)效果。方法:选取2019年1月-2023年3月本院接受治疗的肺炎合并RF新生儿102例,随机分为常规组(NCPAP序贯常规鼻导管吸氧治疗)和观察... 详细信息

目的:探究经鼻持续气道正压通气(NCPAP)序贯高流量鼻导管湿化氧疗(HHFNC)治疗新生儿肺炎合并呼吸衰竭(RF)效果。方法:选取2019年1月-2023年3月本院接受治疗的肺炎合并RF新生儿102例,随机分为常规组(NCPAP序贯常规鼻导管吸氧治疗)和观察组(NCPAP序贯HHFNC治疗)各51例,比较两组治疗后临床症状消失时间,治疗24 h后血气指标、炎症因子水平、免疫功能。结果:治疗后临床症状消失时间观察组短于常规组;治疗24 h后,两组血氧分压、氧合指数及pH水平均升高且观察组(76.36±7.28 mmHg、204.75±20.15mmHg、7.25±0.59)均高于常规组(72.57±7.05mmHg、193.07±19.47mmHg、6.93±0.51),呼吸频率(51.43±3.67次/min)低于常规组(53.82±4.16次/min),两组炎症因子及免疫球蛋白水平均降低,且观察组C反应蛋白(9.25±1.06 mg/L)、中性粒细胞与淋巴细胞比值(1.22±0.31)、降钙素原(1.17±0.31 ng/L)均低于常规组(10.84±1.27 mg/L、1.48±0.36、1.41±0.45 ng/L)(均P<0.05)。结论:NCPAP序贯HHFNC可缩短肺炎合并RF新生儿临床症状改善时间,调节患儿血气指标及免疫功能,减轻炎症反应。

关键词：新生儿肺炎合并呼吸衰竭经鼻持续气道正压通气高流量鼻导管湿化氧疗免疫功能炎症因子

Experimental investigation of the generation of large-amplitude internal solitary wave and its interaction with a submerged slender body

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Science China(Physics,Mechanics & Astronomy) 2014年第2期57卷 301-310页

作者： WEI Gang DU Hui XU XiaoHui zhang yuanming QU ZiYun HU TianQun YOU YunXiang College of Meteorology and Oceanography PLA University of Science and Technology State Key Laboratory of Ocean Engineering Shanghai Jiaotong University

A principle of generating the nonlinear large-amplitude internal wave in a stratified fluid tank with large cross-section is proposed according to the‘jalousie’control mode.A new wave-maker based on the principle was manufactured and the experiments on the generation and evolution of internal solitary wave were *** the validity of the new device and applicability range of the KdV-type internal soliton theory were ***,a measurement technique of hydrodynamic load of internal waves was *** means of accurately measuring slight variations of internal wave forces exerted on a slender body in the tank,their interaction characteristics were *** is shown that through establishing the similarity between the model scale in the stratified fluid tank and the full scale in the numerical simulation the obtained measurement results of internal wave forces are confirmed to be correct.

关键词：相互作用内孤立波大振幅实验车身水下分层流体测量技术

干旱荒漠区不同藓结皮斑块碳通量对降雨量变化的响应

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生态学报 2023年第4期43卷 1584-1595页

作者：李永刚张元明中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室乌鲁木齐830011

藓结皮作为干旱区重要的地表覆盖物,主要呈斑块状分布,其大小能够明显改变土壤和藓类植物的含水量、蒸散量以及养分含量,对荒漠地表的稳定和碳循环具有重要作用。降雨是干旱荒漠区土壤水分的主要来源,能够直接影响藓结皮的生理活性,决... 详细信息

藓结皮作为干旱区重要的地表覆盖物,主要呈斑块状分布,其大小能够明显改变土壤和藓类植物的含水量、蒸散量以及养分含量,对荒漠地表的稳定和碳循环具有重要作用。降雨是干旱荒漠区土壤水分的主要来源,能够直接影响藓结皮的生理活性,决定了藓结皮土壤的碳源-碳汇效应。然而不同大小藓结皮斑块碳通量对降雨的响应是否不同并不清楚。以古尔班通古特沙漠齿肋赤藓(Syntrichia caninervis Mitt.)斑块为研究对象,施加不同降雨量(0 mm、2 mm、5 mm、15 mm降雨),连续54 h测定不同大小藓结皮斑块(直径为:4.6 cm、5.6 cm、10 cm)碳通量。结果显示:(1)在2 mm和5 mm降雨量下,不同斑块大小藓结皮静碳交换速率连续54 h内的变化趋势相似,直径为4.6 cm和5.6 cm斑块累积碳通量呈负值,表现为碳固定,10 cm斑块则相反表现为碳释放,在15 mm降雨量下,不同斑块大小藓结皮碳通量均表现为碳释放,直径为10 cm的藓结皮斑块净碳交换速率随时间的变化趋势与直径5.6 cm和4.6 cm藓结皮斑块不同;(2)斑块大小和降雨量变化均显著影响藓结皮斑块碳通量,土壤含水量与静碳交换速率呈显著的正效应,且土壤含水量与静碳交换速率间斜率随斑块面积增加呈增加趋势,土壤温度低于25℃时,藓结皮斑块碳通量随土壤温度增加呈降低趋势,高于25℃时,土壤温度对藓结皮斑块碳通量无显著影响。因此,未来荒漠藓结皮碳通量研究中应考虑降雨量和斑块大小对藓结皮碳通量的影响;且从碳收支平衡解释小型藓结皮斑块对荒漠小降雨脉冲有较强的适应性,同时为评估未来荒漠降水格局变化下荒漠藓结皮斑块组成、分布以及荒漠生态系统碳循环研究提供科学理论基础。

关键词：藓结皮斑块碳通量降雨量土壤含水量斑块大小

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Characteristics of spore germination and protonemal development in Hypnum pacleseens

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Frontiers in Biology 2006年第3期1卷 225-229页

作者： HUANG Shiliang LI Min ZHAO Jiancheng zhang yuanming WANG Zhenjie College of Life Science Hebei Normal UniversityShijiazhuang 050016China Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China

The spore germination,protonemal development,and gametophyte differentiation of Hypnum pacleseens were observed in *** showed that spore germination of Hypnum pacleseens occured within the *** protonema is massive with filamentous chloronema formed *** terminal part of the chloronema differentiated into filamentous caulonema and its rhizoid was derived from the apical cell of the filamentous *** initial cell of gametophyte differentiated from chloronema and ***-type of Hypnum pacleseens is developmentally similar to Glyphmitrium-type.

关键词： mosses Hypnum pacleseens spore germination protonemal development sporeling-type

Characteristics and utilization of plant diversity and resources in Central Asia

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Regional Sustainability 2020年第1期1卷 1-10页

作者： yuanming zhang Daoyuan zhang Wenjun Li Yaoming Li Chi zhang Kaiyun Guan Borong Pan State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi830011China

The geographical region of Central Asia comprises Kazakhstan,Kyrgyzstan,Tajikistan,Uzbekistan,Turkmenistan,and the Xinjiang Uygur Autonomous Region of *** Asia’s temperate forests,steppes,and sandy deserts,including riparian tugai forests,have been identified by the World Wide Fund for Nature as Global 200 ecoregions,and the Mountains of Central Asia are considered biodiversity ***,we describe and analyze the diverse characteristics and utilization of plant diversity and resources of the *** confirm that there are 9520 species of higher plants,20%of which are endemic species,belonging to 138 families and 1176 *** vegetation geography of Central Asia can be divided into 5 provinces and 33 districts,and more than 65%species have a Central Asian geographical distribution *** resource utilization can be grouped into 5 categories and 31 subcategories,including food,medicine,industry,environmental protection,construction,and plant *** this review,we also discuss the principal threats to plant biodiversity in Central Asia posed by global climate change and offer recommendations for conservation strategies.

关键词： Flora Plant resources Biodiversity Vegetation types Central Asia

PREPARATION OF HETEROPOLY COMPOUND MEMBRANE AND ITS CATALYTIC PROPERTY

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Chinese Journal of Catalysis 1999年第6期20卷 589-590页

作者： zhang yuanming, Song Ruiqi, Mao Xuan, Yang Jun, Zhong Bangke (Department of Chemistry, Jinan University, Guangzhou 510632) 暨南大学广东广州

Heteropoly compounds (HPC), a kind of polyoxometallates, with their strong acidity and oxidative ability, are good homogeneous and heterogeneous catalysts in both acid-catalyzed and selective oxidation reactions, and have been widely used in petroleum and fine chemical industries. Owing to the diversity in their composition and structure, the catalytic properties of HPC can be altered in a wide range. Among them, the heteropolyanions with Keggin structure have been studied by far the most,especially on their applications in heterogeneous catalysis. However, since they are thermally unstable at high temperatures, their utilization in this field has been restricted. In the last ten years, inorganic membranes have been proved to be beneficial to heterogeneous catalytic processes for their high selectivity and good heat-conductivity. And the sol-gel method, one of the most common approaches to prepare inorganic membranes, is becoming mature. Here a sol-gel method to prepare a porous HPC membrane is reported. The catalytic performance of the membrane was tested through a model reaction, the selective oxidation of t-BuOH.

关键词： heteropoly compound inorganic membrane butanol selective oxidation methacrylic acid