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Changes in Mean and Extreme Temperature and Precipitation over the Arid Region of Northwestern China： Observation and Projection

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Advances in Atmospheric Sciences 2017年第3期34卷 289-305页

作者： Yujie WANG Botao ZHOU Dahe QIN Jia wu Rong gao Lianchun song School of Atmospheric Sciences Nanjing University Nanjing 210046 China National Climate Center China Meteorological Administration Beijing 100081 China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Nanjing 210044 China Northwest Climate Center of Gansu Meteorological Bureau Lanzhou 730020 China

This paper reports a comprehensive study on the observed and projected spatiotemporal changes in mean and extreme climate over the arid region of northwestern China, based on gridded observation data and CMIP5 simulations under the RCP4.5 and RCP8.5 scenarios. The observational results reveal an increase in annual mean temperature since 1961, largely attributable to the increase in minimum temperature. The annual mean precipitation also exhibits a significant increasing tendency. The precipitation amount in the most recent decade was greater than in any preceding decade since 1961. Seasonally, the greatest increase in temperature and precipitation appears in winter and in summer, respectively. Widespread significant changes in temperature-related extremes are consistent with warming, with decreases in cold extremes and increases in warm extremes. The warming of the coldest night is greater than that of the warmest day, and changes in cold and warm nights are more evident than for cold and warm days. Extreme precipitation and wet days exhibit an increasing trend, and the maximum number of consecutive dry days shows a tendency toward shorter duration. Multi-model ensemble mean projections indicate an overall continual increase in temperature and precipitation during the 21 st century. Decreases in cold extremes, increases in warm extremes, intensification of extreme precipitation, increases in wet days, and decreases in consecutive dry days, are expected under both emissions scenarios, with larger changes corresponding to stronger radiative forcing.

关键词： climate change arid region observation CMIP5 projection

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Structures and macrosegregation of a 2024 aluminum alloy fabricated by direct chill casting with double cooling field

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China Foundry 2022年第1期19卷 1-8页

作者： Cheng Zhu Zhi-hao Zhao Qing-feng Zhu gao-song Wang Yu-bo Zuo gao-wu Qin Research Center for Metallic Wires School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Key Laboratory of Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

Central region coarse grains and centerline segregation are common defects in aluminum ingots fabricated by direct chill(DC)casting.A double cooling field was introduced into the DC casting process to reduce these defects,whereby the external cooling was supplied by the mold and water jets,and intercooling was achieved by inserting a rod of the same alloy into the molten pool along the central axis of the *** than forming a good metallurgical interface during solid-liquid compound casting,in the present work,the purpose of inserting the rod is to enforce internal cooling and consequently decrease the sump ***,the insertion provides more nucleation sites with the unmoltenα-Al *** structure and the macrosegregation of 2024 Al alloy ingots prepared by DC casting with and without the inserts were *** show that when the inserting position is 50 mm above the upper edge of the graphite ring,significant grain refinement in the central region of the ingot and a reduced centerline segregation are achieved.

关键词： aluminum alloy direct chill casting double cooling field grain refinement macrosegregation

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Extraction of palladium(Ⅱ) from hydrochloride solutions with 2-n-octyl-4-isothiazolin-3-one as novel extractant

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Rare Metals 2013年第4期32卷 425-430页

作者： song-Ping wu School of Chemistry and Chemical Engineering South China University of Technology

Solvent extraction of palladium （Ⅱ） from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one （OIT）/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.96 % and 98.26 % palladium （Ⅱ） could be effectively extracted with 0.018 mol·L^-1 OIT/cyclohexane of 0.1 and 4.0 mol·L^-1 HCl medium, respectively. Nonpolar solvent and low acidity could improve the extracting efficiency, and successfully strip palladium （Ⅱ） from the loaded organic phase was achieved with 0.5 mol·L^-1 （NH2）2CS solution. It was proposed that the extraction of Pd com-plexes from HCl medium proceeded through the ion-association mechanism by slope method, NMR and FF-IR spectra.

关键词： Solvent extraction Palladium 2-n-octyl-4-isothiazolin-3-one OIT Stripping

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Characteristics of soil nutrients and their relationship with soil microbial properties in Artemisia sacrorum communities in the loess hilly region

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International Journal of Agricultural and Biological Engineering 2018年第4期11卷 127-134页

作者： Lijuan song Weiyang Liu Huifeng wu Tian gao Wenfang Hao College of Life Sciences Northwest A&F UniversityYangling 712100China College of Life Sciences Cangzhou Normal UniversityCangzhou 061000China College of Plant and Science Tarim UniversityAlarXinjiang 843300China College of Landscape Architecture and Arts Northwest A&F UniversityYangling 712100China

Artemisia sacrorum communities with different growth years were selected to analyse soil nutrient characteristics,the variation in soil microbial properties,and their relationships in the loess hilly *** results showed that with an increase in the number of growth years,soil microbial biomass carbon and nitrogen contents as well as soil phosphatase and urease activities initially decreased and then increased in the *** *** soil organic carbon,organic nitrogen,and total nitrogen contents as well as soil respiration rate showed an increasing trend and reached a maximum at age(a)*** soil available phosphorus content first decreased and then increased,with the lowest level observed at 18 *** contrast,soil available potassium initially increased and then *** microbial biomass carbon had a significant positive correlation with soil organic carbon,total nitrogen and organic nitrogen,while soil respiration had a significant positive correlation with organic nitrogen,soil phosphatase and organic *** respiration had a highly significant positive correlation with organic carbon and total nitrogen,while soil phosphatase had a highly significant positive correlation with total nitrogen and organic *** the *** communities,the soil organic carbon and total nitrogen contents were mainly affected by soil respiration,soil available potassium content was mainly affected by soil urease activity,and soil organic nitrogen content was mainly affected by soil phosphatase *** findings indicate that soil basal respiration,urease activity and phosphatase activity were the major microbial factors affecting the characteristics of the soil nutrients in the *** *** conclusion,the natural restoration process of *** communities can enhance soil microbial activity and improve soil quality.

关键词： loess hilly soil nutrients soil microbial biomass soil enzyme activities soil basal respiration rate

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A new isoquinoline derivative from the leaves of Magnolia sieboldii ***

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Chinese Chemical Letters 2010年第12期21卷 1446-1448页

作者： Di wu Ru Ping Wang Shao Jiang song Li Jun wu Hui Yuan gao The Liaoning Provincial Public Security Office Shenyang 110032 China School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education Shenyang Pharmaceutical University Shenyang 110016 China

Magnoline（1）,a new isoquinoline derivative,was isolated from the leaves of Magnolia sieboldii ***（Magnoliaceae）.Its structure was elucidated on the basis of spectral analysis including 1D,2D NMR and HR-TOF-MS.

关键词： Magnolia sieboldii K. Koch Isoquinoline Structural identification

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Arabidopsis calcium-dependent protein kinase CPK28 is potentially involved in the response to osmotic stress

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Chinese Science Bulletin 2014年第11期59卷 1113-1122页

作者： Anli gao Qingyang wu Yu Zhang Yuchen Miao Chunpeng song State Key Laboratory of Cotton Biology Institute of Plant Stress BiologyCollege of Life SciencesHenan University

As calcium sensors, plant calcium-dependent protein kinases(CDPKs) play important roles in plants' responses to various abiotic stresses. Here, we report the functional characterization of CPK28, a member of the CDPK family in Arabidopsis, in response to osmotic *** cpk28 mutant, a loss-of-function mutant, exhibited an NaCl- and mannitol-sensitive phenotype in green cotyledons, while CPK28-overexpressing plants displayed stronger tolerance to NaCl and mannitol stresses than wildtype plants. Reverse transcriptase-polymerase chain reaction and beta-glucuronidase staining assays showed that NaCl and mannitol stresses induced CPK28. CPK28-overexpressing lines accumulated significantly more proline relative to wild-type plants and mutant plants under NaCl and mannitol stresses. Transient expression of CPK28-GFP in mesophyll cell protoplasts, as well as stable transgenic lines expressing CPK28-GFP, showed that CPK28 was localized in the plasma membrane. Expression levels of known stress-responsive genes were not significantly altered in the null mutant and overexpression lines,suggesting that CPK28 possibly mediated the stress response via the regulation of target proteins rather than via regulation at the level of transcription. Meanwhile, CPK28could autophosphorylate. Taken together, these data demonstrated that CPK28, a potential positive regulator, is involved in the response to osmotic stress in Arabidopsis.

关键词：钙依赖蛋白激酶渗透胁迫拟南芥聚合酶链反应 CDPK 应激反应转录水平非生物胁迫

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Constructing Ni_(4)W/WO_(3)/NF with strongly coupled interface for hydrogen evolution in alkaline media

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Rare Metals 2023年第12期42卷 3945-3951页

作者： Teng Zhang Yi-Hong Yu Chuang-Wei Liu gao-wu Qin song Li Key Laboratory for Anisotropy and Texture of Materials(MoE) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China Liaoning Province Engineering Research Center for Technologies of Low-Carbon Steelmaking Northeastern UniversityShenyang 110819China

The pursuit of storing renewable electricity in chemical bonds has encouraged the effort toward developing efficient electrocatalysts for alkaline hydrogen ***,the additional step of water dissociation under alkaline conditions frequently limits the performance of electrocatalysts in alkaline ***,we synthesize Ni_(4)W/WO_(3) with a strongly coupled interface on the Ni foam(NF)by phase transition of NiWO_(4),to enhance the activity for alkaline hydrogen *** is discovered that the strong binding hydroxyl on WO_(3) sites facilitates the dissociation of water,which in turn promotes hydrogen evolution through the synergy effect of strong adsorption of H on Ni *** adsorption/desorption energy of Ni sites is further tuned by the formation of intermetallic *** to the three-dimensional structure and tailored composition,the Ni_(4)W/WO_(3)/NF electrocatalyst exhibits a low overpotential of 31 mV at a current density of10 mA·cm^(-2),with a Tafel slope of 38 mV·dec^(-1).This work provides new opportunities to modulate the catalytic performance of Ni-based electrocatalysts by signifying the metal-oxide interface.

关键词： alkaline interface adsorption

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Two new secoiridoid glucosides from Syringa velutina Kom

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Chinese Chemical Letters 2009年第6期20卷 702-705页

作者： Xue song Feng Yang Qu Zhao Hua wu Lei Xu Dong song Zhang Hui Yuan gao Li Jun wu School of Traditional Chinese Medicines Shenyang Pharmaceutical University Shenyang 110016 China School of Pharmaceutical Sciences China Medical University Shenyang 110001 China Pharmacy Department Mudanjiang Medical University Mudanjiang 157011 China

Chemical investigation of Syringa velutina Kom. led to the isolation of two new secoiridoid glucosides. Their structures were identified as 6＇-O-（6, 7-dihyrofoliamenthoyl）-8-epi-longisidic acid （syrveoside A, 1） and 6＇-O-menthiafoloyl-8-epi-ldngisidic acid （syrveoside B, 2） on the basis of chemical and physicochemical evidence.

关键词： Syringa velutina Kom. Secoiridoid glucosides Syrveoside A Syrveoside B

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A new alkaloid from Castanea mollissima Blume

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Chinese Chemical Letters 2008年第7期19卷 832-834页

作者： Dong song Zhang Hui Yuan gao Xiao Mei song Zhi Shu Tang Li Jun wu School of Traditional Chinese Medicines Shenyang Pharmaceutical University Shenyang 110016 China School of Shanxi University of Chinese Medicines Xianyang 712046 China

A new alkaloid, named 6-（2＇,3＇-dihydroxy-4＇-hydroxymethyl-tetrahydro-furan-1＇-yl）cyclopentadiene[c]pyrrole-1,3-diol, was isolated from the seeds of Castanea mollissima Blume. The structure was elucidated based o... 详细信息

关键词： Castanea mollissima Blume Alkaloid 6-(2',3'-Dihydroxy-4'-hydroxylmethyl-tetrahydro-furan-1'-yl)cyclopentadiene[c]pyrrole-1,3-diol

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The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study

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Neural Regeneration Research 2025年第5期20卷 1505-1512页

作者： Jieying wu Shan Ye Xiangyi Liu Yingsheng Xu Dongsheng Fan Department of Neurology Peking University Third HospitalBeijingChina Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases BeijingChina Key Laboratory for Neuroscience National Health Commission/Ministry of EducationPeking UniversityBeijingChina

Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor *** bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to ***,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is *** address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral *** used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis *** factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb *** results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis *** findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.

关键词： amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread

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