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Alterations to biological soil crusts with alpine meadow retrogressive succession affect seeds germination of three plant species

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Journal of Mountain Science 2016年第11期13卷 1995-2005页

作者： LI Yi-kang OUYANG Jing-zheng LIN Li XU Xing-liang zhang fa-wei DU Yan-gong LIU Shu-li CAO Guang-min HAN fa Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810001China University of Chinese Academy of Sciences Beijing 100049China Institute of Geographic Sciences&Natural Resources Research the Chinese Academy of SciencesBeijing 100101China Liancheng National Nature Reserve of Gansu Province Yongdeng Country 730000China

Biological soil crusts(BSCs) are the important components of alpine meadow *** extent and morphology of BSCs vary greatly with alpine meadow retrogressive succession due to grazing *** is significant interest in impacts of crust composition on plant seed germination,especial l y in(semi-) arid ***,little is known about the influences of BSCs,and their associations with alpine meadow succession,on germination of typical alpine meadow vascular plant *** a full factorial common-gardenexperiment,we studied effects of:(1) crust type,(2) seed position,and(3) surface texture on seed *** chose three typical alpine meadow plant species(*** pratensis,Tibetia himalaica and Potentillen nivea),which belonged to different functional groups(graminoids,legumes,and forbs) and play important roles in all alpine meadow succession *** type and seed position influenced seed germination,and the inhibitory effects of BSCs depended on the crust type and seed species *** major factors influencing seed germination were BSC type,seed position,soil texture,and the interactions between BSC type and seed position; species and seed position; species andsurface texture; and species,crust type,and surface *** crust significantly inhibited germination of all *** position also had a significant effect on seed germination(p face than below the surface,this was especially true for *** within cyanobacteria and lichen *** germination rates of *** on the soil surface were significantly correlated with plant occurrence frequency within the alpine meadow *** poor correlation for the other two species is possibly that they are *** results clearly demonstrated that BSCs can be biological filters during seed germination,depending on the BSC succession *** their influences on seed germination,BSCs can strongly

关键词： Crust type Seed position Microenvironment Germination Tibetan Plateau Vascular plants

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Distribution of soil carbon in different grassland types of the Qinghai-Tibetan Plateau

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Journal of Mountain Science 2016年第10期13卷 1806-1817页

作者： LIU Shu-li DU Yan-gong zhang fa-wei LIN Li LI Yi-kang GUO Xiao-wei LI Qian CAO Guang-min Northwest Institute of Plateau Biology Chinese Academy of SciencesQinghai 810001China University of Chinese Academy of Sciences Beijing 100049China

Accurate estimate of soil carbon storage is essential to reveal the role of soil in global carbon cycle. However, there is large uncertainty on the estimation of soil organic carbon(SOC) storage in grassland among previous studies, and the study on soil inorganic carbon(SIC) is still lack. We surveyed 153 sites during plant peak growing season and estimated SOC and SIC for temperate desert, temperate steppe, alpine steppe, steppe meadow, alpine meadow and swamp, which covered main grassland in the Qinghai Plateau during 2011 to 2012. The results showed that the vertical and spatial distributions of SOC and SIC varied by grassland types. The SOC amount mainly decreased from southeast to northwest, whereas the SIC amount increased from southeast to northwest. The magnitude of SOC amount in the top 50 cm across grassland types ranked by: swamp > alpine meadow >steppe meadow > temperate steppe > alpine steppe > temperate desert, while the SIC amount showed an opposite order. There was a great deal of variation in proportion of SOC and SIC among different grassland types(from 55.17 to 94.59 for SOC and 5.14 to 44.83 for SIC). The total SOC and SIC storage was 5.78 Pg and 1.37 Pg, respectively, in the top 50 cm of soil in Qinghai Province. The mixed linear model revealed that grassland types was the predominant factor in spatial variations of SOC amount while grassland types and soil p H accounted for those of SIC amount. Our results suggested that the community shift of alpine meadow towards alpine grassland induced by climate warming would decrease carbon sequestration capacity by 6.0 kg C m2.

关键词： Soil organic carbon Soil inorganic carbon Different grassland types Carbon distribution Storage

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Effects of continuous tracheal gas insufflation during pressure limited ventilation on pulmonary surfactant in rabbits with acute lung injury

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Chinese Medical Journal 2006年第17期119卷 1415-1420页

作者： ZHU Guang-fa zhang wei ZONG Hua LIANG Ying Department of Respiratory Medicine Beijing Anzhen HospitalCapital University of Medical Science Beijing 100029 China

Background Pulmonary surfactant dysfunction may contribute to the development of ventilator induced lung injury （VILI）. Tracheal gas insuffiation （TGI） is a technique in which fresh gas is introduced into the trachea and augment ventilation by reducing the dead space of ventilatory system, reducing ventilatory pressures and tidal volume （VT） while maintaining constant partial arterial CO2 pressure （PaCO2）. We hypothesised that TGI limited peak inspiratory pressure （PIP） and VT and would minimize conventional mechanical ventilation （CMV） induced pulmonary surfactant dysfunction and thereby attenuate VILI in rabbits with acute lung injury （ALI）. Methods ALI was induced by intratracheal administration of lipopolysaccharide in anaesthetized, ventilated healthy adult rabbits randomly assigned to continuous TGI at 0.5 L/min （TGI group） or CMV group （n=8 for each group）, and subsequently ventilated with limited PIP and VT to maintain PaCO2 within 35 to 45 mmHg for 4 hours. Physiological dead space to VT ratio （VD/VT）, dynamic respiratory compliance （Cdyn） and partial arterial O2 pressure （PaO2） were monitored. After ventilation, lungs were analysed for total phospholipids （TPL）, total proteins （TP）, pulmonary surfactant small to large aggregates ratio （SA/LA） in bronchoalveolar lavage fluid （BALF） and for determination of alveolar volume density （Vv）, myeloperoxidase and interleukin （IL）-8. Results TGI resulted in significant （P〈0.05 or P〈0.01） decrease in PIP [（22.4±1.8） cmH20 vs （29.5±1.1） cmH2O], VT [（6.9±1.3） ml/kg vs （9.8±1.11） ml/kg], VD/VT [（32±5）% vs （46±2）%], TP [（109±22） mg/kg vs （187±25） mg/kg], SA/LA （2.5±0.4 vs 5.4±0.7）, myeloperoxidase [（6.2±0.5） U/g tissue vs （12.3±0.8） U/g tissue] and IL-8 [（987±106） ng/g tissue vs （24±3） mN/m] of BALF, and significant （P〈0.05） increase in Cdyn [（0.47±0.02） ml·cmH2O^-1·kg^-1 vs （0.31±0.02） ml·cmH2O^-1·kg^-1], PaO2 [（175±24） mmHg vs （135±26） mmHg], TPL/TP （52±8 vs 33±11） and Vv （0.65±0.05 vs 0.44±0.07） as compared with CMV

关键词： tracheal gas insufflation acute lung injury pulmonary surfactant ventilator induced lung injury mechanical ventilation

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Effects of long-term grazing exclusion on vegetation structure,soil water holding capacity,carbon and nitrogen sequestration capacity in an alpine meadow on the Tibetan Plateau

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Journal of Mountain Science 2023年第3期20卷 779-791页

作者： YANG Yong-sheng zhang fa-wei XIE Xian-rong WANG Jun-bang LI Ying-nian HUANG Xiao-tao LI Hui-ting ZHOU Hua-kun Key Laboratory of Adaptation and Evolution of Plateau Biota and Key Laboratory of Restoration Ecology in Cold Region of Qinghai Province Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China Qinghai Haibei National Field Research Station of Alpine Grassland Ecosystem Xining 810008China Xi Ning Municipal Beishan Forestry farm Xining 810003China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Grazing exclusion is one of the primary management practices used to restore degraded grasslands on the Tibetan ***,to date,the effects of long-term grazing exclusion measures on the process of restoring degraded alpine meadows have not been *** this study,moderately degraded plots,in which the vegetation coverage was approximately 65%and the dominant plant species was Potentilla anserina L,with grazing exclusion for 2 to 23 years,were selected in alpine meadows of Haibei in Qinghai-Tibet *** coverage,plant height,biomass,soil bulk density,saturated water content,soil organic carbon(SOC)and total nitrogen(TN)were *** results were as follows:(1)With aboveground biomass and total saturated water content at 0-40 cm depth,the average SOC and TN contents in moderately degraded alpine meadows increased as a power function,and the plant height increased as a log function.(2)The average soil bulk density at 0-40 cm depth first decreased and then increased with increasing grazing exclusion duration,and the minimum value of 0.90 g·cm^(-3) was reached at 15.23 *** plant coverage,total belowground biomass at 0-40 cm depth,total aboveground and belowground biomass first increased and then decreased,their maximum values(80.49%,2452.92g·m^(-2),2891.06 g·m^(-2))were reached at 9.41,9.46 and 10.25 years,***-term grazing exclusion is apparently harmful for the sustainable restoration of degraded alpine *** optimal duration of grazing exclusion for the restoration of moderately degraded alpine meadows was 10 *** research suggests that moderate disturbance should be allowed in moderately degraded alpine meadows after 10years of grazing exclusion.

关键词： Long-term grazing exclusion Soil water holdingcapacity Soilcarbonand nitrogen sequestration Biomass Alpine meadow

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Effectiveness and safety of noninvasive positive-pressure ventilation for severe hypercapnic encephalopathy due to acute exacerbation of chronic obstructive pulmonary disease:a prospective case-control study

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Chinese Medical Journal 2007年第24期120卷 2204-2209页

作者： ZHU Guang-fa zhang wei ZONG Hua XU Qiu-fen LIANG Ying Department of Respiratory Medicine Beijing Anzhen HospitalCapital Medical University Beijing 100029 China

Background Although severe encephalopathy has been proposed as a possible contraindication to the use of noninvasive positive-pressure ventilation （NPPV）, increasing clinical reports showed it was effective in patients with impaired consciousness and even coma secondary to acute respiratory failure, especially hypercapnic acute respiratory failure （HARF）. To further evaluate the effectiveness and safety of NPPV for severe hypercapnic encephalopathy, a prospective case-control study was conducted at a university respiratory intensive care unit （RICU） in patients with acute exacerbation of chronic obstructive pulmonary disease （AECOPD） during the past 3 years. Methods Forty-three of 68 consecutive AECOPD patients requiring ventilatory support for HARF were divided into 2 groups, which were carefully matched for age, sex, COPD course, tobacco use and previous hospitalization history, according to the severity of encephalopathy, 22 patients with Glasgow coma scale （GCS）〈10 served as group A and 21 with GCS 〉10 as group B. Results Compared with group B, group A had a higher level of baseline arterial partial CO2 pressure （（102±27） mmHg vs （74±17） mmHg, P〈0.01）, lower levels of GCS （7.5±1.9 vs 12.2±1.8, P〈0.01）, arterial pH value （7.18±0.06 vs 7.28±0.07, P〈0.01） and partial 02 pressure/fraction of inspired 02 ratio （168±39 vs 189±33, P〈0.05）. The NPPV success rate and hospital mortality were 73% （16/22） and 14% （3/22） respectively in group A, which were comparable to those in group B （68% （15/21） and 14% （3/21） respectively, all P〉0.05）, but group A needed an average of 7 cmH20 higher of maximal pressure support during NPPV, and 4, 4 and 7 days longer of NPPV time, RICU stay and hospital stay respectively than group B （P〈0.05 or P〈0.01）. NPPV therapy failed in 12 patients （6 in each group） because of excessive airway secretions （7 patients）, hemodynamic instability （2）, worsening of dyspnea and deterioration of gas exchange （2）, and gastric content aspiration （1）.

关键词： acute respiratory failure hypercapnia encephalopathy chronic obstructive pulmonary disease noninvasive positive pressure ventilation

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Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng zhang Chenyang zhang Linlin Wu wei Sun Hongliang zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

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Recent progress in constructing fluorinated solid-electrolyte interphases for stable lithium metal anodes

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 270-291页

作者： Di zhang Pengfei Lv wei Qin Xin He Yuanhua He Civil Aircraft Fire Science and Safety Engineering Key Laboratory of Sichuan Province College of Civil Aviation Safety EngineeringCivil Aviation Flight University of ChinaGuanghan 618307China School of Chemical Engineering Sichuan UniversityChengdu 610065China

Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific ***,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit *** a stable SEI is essential for the long-term operation of the ***-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte *** the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode *** paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal *** focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI *** instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the *** metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling ***,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future *** alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion *** summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.

关键词： LiF lithium metal anodes solid-electrolyte interphase interface cycling stability

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From waste to wealth:Coal tar residue derived carbon materials as low-cost anodes for potassium-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 464-475页

作者： Zhonghua Lu Jun Shen Xin zhang Lingcong Chao Liang Chen Ding zhang Tao wei Shoudong Xu College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China College of Chemistry Taiyuan University of TechnologyTaiyuan 030024China School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan 430205China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China

Carbon materials are widely recognized as highly promising electrode materials for various energy storage system *** tar residues(CTR),as a type of carbon-rich solid waste with high value-added utilization,are crucially important for the development of a more sustainable *** this study,we employed a straightforward direct carbonization method within the temperature range of 700-1000℃to convert the worthless solid waste CTR into economically valuable carbon materials as anodes for potassium-ion batteries(PIBs).The effect of carbonization temperature on the microstructure and the potassium ions storage properties of CTR-derived carbons(CTRCs)were systematically explored by structural and morphological characterization,alongside electrochemical performances *** on the co-regulation between the turbine layers,crystal structure,pore structure,functional groups,and electrical conductivity of CTR-derived carbon carbonized at 900℃(CTRC-900H),the electrode material with high reversible capacity of 265.6m Ah·g^(-1)at 50 m A·g^(-1),a desirable cycling stability with 93.8%capacity retention even after 100 cycles,and the remarkable rate performance for PIBs were ***,cyclic voltammetry(CV)at different scan rates and galvanostatic intermittent titration technique(GITT)have been employed to explore the potassium ions storage mechanism and electrochemical kinetics of *** indicate that the electrode behavior is predominantly governed by surface-induced capacitive processes,particularly under high current densities,with the potassium storage mechanism characterized by an“adsorption-weak intercalation”*** work highlights the potential of CTR-based carbon as a promising electrode material category suitable for high-performance PIBs electrodes,while also provides valuable insights into the new avenues for the high value-added utilization of CTR.

关键词： coal tar residue carbon materials anode potassium-ion batteries high value-added

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斯木塔斯台阶式陡槽溢洪道水力特性模型试验研究

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中国农村水利水电 2011年第1期 93-96页

作者：张为法刘韩生西北农林科技大学水利与建筑工程学院陕西杨凌712100

斯木塔斯水电站原设计方案泄水建筑物中溢洪道采用了台阶式消能方式,为了论证在高水头,小单宽流量下台阶式溢洪道应用的合理性,有必要对设计方案进行模型试验的研究。借助大比尺的模型试验,对该溢洪道段的流态,压强,掺气,消能率等进行... 详细信息

斯木塔斯水电站原设计方案泄水建筑物中溢洪道采用了台阶式消能方式,为了论证在高水头,小单宽流量下台阶式溢洪道应用的合理性,有必要对设计方案进行模型试验的研究。借助大比尺的模型试验,对该溢洪道段的流态,压强,掺气,消能率等进行了观测。试验结果表明各项水力特性良好,消能效果显著,满足工程实际的需要,为工程决策提供了科学依据。模型试验验证了台阶消能工在高水头,小单宽流量下应用的可行性,对类似工程具有一定的参考价值。

关键词：台阶溢洪道掺气浓度时均压强消能率

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台阶式溢洪道滑行水流消能特性研究

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长江科学院院报 2014年第6期31卷 37-40页

作者：张峰刘韩生张为法西北农林科技大学水利与建筑工程学院陕西杨凌712100 中国水电工程顾问集团西北勘察设计研究院西安710000

台阶式溢洪道消能率无法详细反映其消能特性,为了突出反映台阶消能作用,从总消能水头中扣除光滑溢洪道原有消能水头得到纯台阶消能部分,计算了单位高度纯台阶消能率,以及台阶消能所占总消能的比重。结果表明:滑行水流的单位高度纯台阶... 详细信息

台阶式溢洪道消能率无法详细反映其消能特性,为了突出反映台阶消能作用,从总消能水头中扣除光滑溢洪道原有消能水头得到纯台阶消能部分,计算了单位高度纯台阶消能率,以及台阶消能所占总消能的比重。结果表明:滑行水流的单位高度纯台阶消能率约为0.80%/m^0.83%/m,与单宽流量和台阶数目均无关,随台阶高度增大增幅为4.5%;纯台阶消能所占总消能比重随单宽流量增大而增加,随台阶数目增多而减小;此外,还对单宽流量增加时消能率下降的原因进行了探讨。结果分析表明:大单宽流量消能率下降是由于光滑溢洪道能作用降低而纯台阶消能不变导致的。

关键词：台阶式溢洪道滑行水流单宽流量台阶高度消能率

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