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Dynamic response to climate change in the radial growth of Picea schrenkiana in western Tien Shan,China

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Journal of Forestry Research 2022年第1期33卷 147-157页

作者： liang jiao Shengjie Wang Ke Chen Xiaoping Liu College of Geography and Environment Science Northwest Normal UniversityLanzhou 730070People’s Republic of China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875People’s Republic of China

Forests are important ecosystems for economic and social ***,the response of tree radial growth to climate has produced‘divergent problems'at high latitudes under global *** this study,the response stability and trend of Picea schrenkiana radial growth to variability in climate factors were analyzed in the mid-latitudes of the western Tien Shan *** growth of *** was mainly limited by minimum and mean *** divergent responses of radial growth occurred in response to the minimum and mean temperatures at the beginning of the growing season(April–May)of the current year,but responses to drought occurred in July–September of the previous *** the mean and minimum temperatures in June–September of the current year were both *** growth first increased and then decreased according to the basal area increment,with a gradual increase in ***,forest ecosystems in mountainous arid areas will be increasingly affected by future climate warming.

关键词： Dendroecology Divergent response Climate change Forest degradation Western Tien Shan mountains

Stability evaluation of radial growth of Picea schrenkiana in different age groups in response to climate change in the eastern Tianshan Mountains

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Journal of Mountain Science 2020年第7期17卷 1735-1748页

作者： jiao liang CHEN Ke WANG Sheng-jie LIU Xiao-ping College of Geography and Environment Science Northwest Normal UniversityLanzhou730070China

Global warming causes an unstable response in tree radial growth at high latitudes in the Northern ***,different climatic responses of different age groups of trees have been found due to their different physiological *** this study,the response stability and growth trend of three age groups(young<100 a,middle 100-200 a,old≥200 a)of Picea schrenkiana(Schrenk spruce)to climate change and the causes of the different responses in different age groups were analyzed in the relatively dry climate of the eastern Tianshan *** results showed that:(1)With the abrupt increase in temperature in 1989,the annual mean minimum temperature became the dominant radial growth-limiting factor of the three age groups of Schrenk spruce.(2)The radial growth of the middle and young groups was more sensitive than that of the old group based on growth-climate correlation analysis.(3)The radial growth of the different age groups had different responses to climate factors,and all age groups were unstable on time scales.(4)The trend of the linear regression simulation of the basal area increment(BAI)indicated that the Schrenk spruce had the same growth trends in different age groups with growth first increased and then decreased;however,the decreased growth rate was higher in the middle and young age groups than in the old age group after the abrupt increase in ***,we should pay active attention to the impact of drought on Schrenk spruce in the eastern Tianshan Mountains and should particularly strengthen the conservation and management of the middle and young age groups.

关键词： Divergent response Global warming Tree age Annual mean minimum temperature Schrenk spruce Tianshan Mountains

Synthesis of the water-compatible p-acetaminophen resin and its adsorption performances for vanillin in aqueous solution

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Chinese Chemical Letters 2012年第1期23卷 123-126页

作者： Gu Qing Xiao Li Ping Long jiao liang Wang College of Chemistry and Environmental Engineering Hunan City UniversityYiyang 413000China

A novel p-acetaminophen resin（named as GQ-1） was synthesized with chloromethylated polystyrene and *** can be used without any wetting *** objective of this work was to study the adsorption performances for vanillin onto GQ-1 with two kinds of the hydrogen bond site of acetamino group and hydroxyl *** results showed that the adsorption property of vanillin onto GQ-1 was superior to XAD-4,H103,NDA150,and *** adsorption capacity of vanillin onto GQ-1 is not greatly discrepant until the solution pH is higher than *** saturated adsorption quantity of vanillin was up to 141.32 mg/mL（wet resin） according to the dynamic adsorption and desorption experiments at 293 *** resin could be regenerated by 7 BV ethanol.

关键词： p-Acetaminophen resin Vanillin Adsorption

Precipitation Behavior of Cu-1.9Be-0.3Ni-0.15Co Alloy During Aging

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 307-315页

作者： Yan-Chuan Tang Yong-Lin Kang Li-Juan Yue Xiao-liang jiao School of Materials Science and Engineering University of Science and Technology Beijing CNMC Ningxia Orient Group Co. Ltd.

In this paper,the evolutions of microstructure and mechanical properties of Cu-l.9Be-0.3Ni-0.15Co alloy were *** alloys in the condition of the solution treated（soft state） and 37% cold rolled（hard state） were aged at 320 ℃for different time,*** mechanical properties,electrical conductivity and microstructure of the alloy aged for different time were ***,the precipitation kinetics of Cu-1.9Be-0.3Ni-0.15Co alloys was investigated.X-ray diffraction and transmission electron microscopy results reveal that both continuous precipitation and discontinuous precipitation existed in the hard-state Cu-l.9Be-0.3Ni-0.15Co alloy during the whole aging process;the sequence of continuous precipitation is *** →γ″→γ′→γ.Furthermore,the precipitation transformation mechanism of softstate alloy is homogeneous nucleation,while hard-state alloy shows the heterogeneous nucleation（interface nucleation）with the nucleation rate of both states decaying rapidly to zero during aging at 320 ℃.

关键词： Cu-1.9Be-0.3Ni-0.15Co alloy Aging Microstructure Mechanical property Electrical property Precipitation kinetics

Synergistic anti-tumor effect of recombinant chicken fibroblast growth factor receptor-1-mediated anti-angiogenesis and low-dose gemcitabine in a mouse colon adenocarcinoma model

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World Journal of Gastroenterology 2007年第17期13卷 2484-2489页

作者： Shao-Jiang Zheng Shao-Ping Zheng Feng-Ying Huang Chang-liang jiao Ren-liang Wu Department of Pathology Tongji Medical College Huazhong University of Science andTechnology Pulmonary Disease Laboratory The Ministry ofHealth of China Wuhan 430030 Hubei Province China Department of Pathology Hainan Medical College and The Affiliated Hospital Haikou571101 Hainan Province China Hainan Province KeyLaboratory of Tropical Medicine Hainan Medical CollegeHaikou 571101 Hainan Province China Department of Ultrasonography UnionHospital Tongji Medical College Huazhong University ofScience.and Technology Wuhan 430022 Hubei Province China

AIM： To evaluate whether the combination of recom- binant chicken fibroblast growth factor receptor -1 （FGFR-1） protein vaccine （cFR-I） combined with low- dose gemcitabine would improve anti-tumor efficacy in a mouse CT26 colon adenocarcinoma （CT26） model.METHODS： The CT26 model was established in BABL/c mice. Seven days after tumor ceil injection, mice were randomly divided into four groups： combination therapy, cFR-1 alone, gemcitabine alone, and normal saline groups. Tumor growth, survival rate of tumor-bearing mice, and systemic toxicity were observed. The presence of anti-tumor auto-antibodies was detected by Western blot analysis and enzyme-linked immunospot assay, microvessel density （MVD） of the tumors and tumor cell proliferation were detected by Immunohistochemistry staining, and tumor cell apoptosis was detected by TdT- mediated biotinylated-dUTP nick end label staining.RESULTS： The combination therapy results in apparent decreases in tumor volume, microvessel density and tumor cell proliferation, and an increase in apoptosis without obvious side-effects as compared with either therapy alone or normal control groups. Also, both auto- antibodies and the antibody-producing B cells against mouse FGFR-1 were detected in mice immunized with cFR-1 vaccine alone or with combination therapy, but not in non-immunized mice. In addition, the deposition of auto-antibodies on endothelial cells from mice immunized with cFR-1 was observed by immunofluorescent stain- ing, but not on endothelial cells from control groups. Synergistic indexes of tumor volume, MVD, cell apoptosis and proliferation in the combination therapy group were 1.71 vs 1.15 vs 1.11 and 1.04, respectively, 31 d after tumor cell injection.CONCLUSION： The combination of cFR-l-mediated antiangiogenesis and low-dose gemcitabine synergistically enhances the anti-tumor activity without overt toxicity in mice.

关键词： Fibroblast growth factor receptor-i Gerncitabine Anti-angiogenesis Vaccine Combinationtherapy

Elevation response of above-ground net primary productivity for Picea crassifolia to climate change in Qilian Mountains of Northwest China based on tree rings

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Journal of Geographical Sciences 2024年第1期34卷 146-164页

作者： WU Xuan jiao liang DU Dashi XUE Ruhong WEI Mengyuan ZHANG Peng College of Geography and Environment Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis Northwest Normal UniversityLanzhou 730070China

Current ecosystem models used to simulate global terrestrial carbon balance generally suggest that terrestrial landscapes are stable and mature,but terrestrial net primary productivity(NPP)data estimated without accounting for disturbances in species composition,environment,structure,and ecological characteristics will reduce the accuracy of the global carbon ***,the steady-state assumption and neglect of elevation-related changes in forest NPP is a *** Qilian Mountains are located in continental climate zone,and vegetation is highly sensitive to climate *** quantified aboveground biomass(AGB)and aboveground net primary productivity(ANPP)sequences at three elevations using field-collected tree rings of Picea crassifolia in Qilian Mountains of Northwest *** results showed that(1)There were significant differences between AGB and ANPP at the three elevations,and the growth rate of AGB was the highest at the low elevation(55.99 t ha^(–1)10a^(–1)).(2)There are differences in the response relationship between the ANPP and climate factors at the three elevations,and drought stress is the main climate signal affecting the change of ANPP.(3)Under the future climate scenario,drought stress intensifies,and the predicted decline trend of ANPP at the three elevations from mid-century to the end of this century is–0.025 t ha^(–1)10a^(–1),respectively;–0.022 t ha^(–1)10a^(–1);At–0.246 t ha^(–1)10a^(–1),the level of forest productivity was significantly *** results reveal the elevation gradient differences in forest productivity levels and provide key information for studying the carbon sink potential of boreal forests.

关键词： global climate change tree ring aboveground net primary productivity aboveground biomass drought stress Qilian Mountains

Radial growth in Qinghai spruce is most sensitive to severe drought in the Qilian Mountains of Northwest China

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Journal of Forestry Research 2024年第3期35卷 73-86页

作者： Xuge Wang liang jiao Ruhong Xue Peng Zhang Dashi Du Mengyuan Wei Qian Li College of Geography and Environmental Science Northwest Normal UniversityNo.967Anning East RoadLanzhou 730070People's Republic of China Key Laboratory of Resource Environment and Sustainable Development of Oasis Northwest Normal UniversityLanzhou 730070Gansu ProvincePeople's Republicof China

Global warming and frequent extreme drought events lead to tree death and extensive forest decline,but the underlying mechanism is not *** drought years,cambial development is more sensitive to climate change,but in different phenological stages,the response rela-tionship is ***,the dynamic relationship between tree radial growth and climatic/environmental fac-tors needs to be *** thus continuously monitored radial growth of Qinghai spruce(Picea crassifolia Kom.)and environmental factors from January 2021 to November 2022 using point dendrometers and portable meteorological weather stations in the central area of the Qilian *** relationship and stability between the radial growth of Qinghai spruce and environmental factors were compared for different levels of drought in 2021 and *** year 2022 had higher temperatures and less precipitation and was drier than *** with 2021,the growing period in 2022 for Qinghai spruce was 10 days shorter,maximum growth rate(Grmax)was 4.5μm·d^(-1) slower,and the initiation of growth was 6 days *** of Qinghai spruce was always restricted by drought,and the stem radial increment(SRI)was more sensitive to precipitation and air relative *** changes in cumulative radial growth were divided into four phenological stages according to the time of growth onset,cessation,and maximum growth rate(Grmax)of Qinghai *** responses of SRI to climate change were stronger in Stage 3 and Stage 4 of 2021 and stronger in Stage 1(initiation growth stage)and Stage 3 of *** results provide important information on the growth of the trees in response to drought and for specific managing forests as the climate warms.

关键词： Picea crassifolia Radial growth dynamics Severe drought Response stability Point dendrometer

Climate response and radial growth of Pinus tabulaeformis at different altitudes in Qilian Mountains

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Research in Cold and Arid Regions 2021年第6期13卷 496-509页

作者： liang jiao Changliang Qi RuHong Xue Ke Chen XiaoPing Liu College of Geography and Environmental Science Northwest Normal UniversityNo.967Anning East RoadLanzhouGansu 730070China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityNo.19Xinjiekou‐wai StreetHaidian DistrictBeijing 100875China

In order to test whether the relationship between climate and the radial growth of trees is affected by altitude,altitude variability and time stability of climate-influenced radial growth of a dominant conifer,Chinese pine(Pinus tabulaeformis),in the eastern Qilian Mountains were studied against the background of climate change using *** show that 1)droughts at the end of the growing season of last year and during the early and middle growing season of the current year were the main limiting factors for the radial growth of Chinese pine at two altitude gradients;this was determined by analyzing the relationship between tree-ring width chronologies and climate factors.2)The sensitivity of the radial growth of trees to climate change gradually decreased and was affected more by drought stress at a lower altitude.3)An unstable divergence response was observed in the radial growth at the two altitudes,in response to controlling climatic factors;this observation was based on the moving correlation analysis of growth/climate relationships,and the aggravation of drought stress caused by increasing temperature was the main reason.4)The growth rate of Chinese pine at the two altitudes increased at first and then decreased,as measured by basal area increment(BAI)*** temperature rises may have significant effects on mountain forest ecosystems in arid and semi-arid *** management and protection measures should be taken,according to the response patterns of trees to climate change at different altitude gradients.

关键词： eastern Qilian Mountains altitude effect drought stress divergence response Pinus tabulaeformis

Constitutive Relation of Yunjialing Anthracite Under Medium Strain Rate

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Journal of China University of Mining and Technology 2007年第1期17卷 126-132页

作者： GAO Wen-jiao SHAN Ren-liang WANG Gong-cheng CHENG Rui-qiang Department of Civil Engineering China University of Mining ＆ Technology Beijing 100083 China

By means of the split Hopkinson pressure bar （SHPB） testing system, this paper presents a dynamic constitu- tive relation of anthracite at a strain rate of ε =5-85s^-1. Generally, the dynamic stress-strain curve for this kind of anthracite under uni-axial compression has the following four stages： a non-linear loading stage, a plastic yielding stage, a strain-strengthening stage and an unloading breakage stage. Correspondingly, the initial elastic modulus Eb, the yielding strength σs and the ultimate strength σb increase along with an increasing strain rate. The time-dependent elasticity was identified when we analyzed the mechanical properties of anthracite. Based on characteristics of measured dynamic stress-strain curves and an analysis of existing rock dynamic constitutive models, as well as a preparatory simulation, a new visco-elastic damage model has been introduced in this paper. A linear spring is put parallel to two Maxwell units with different relaxation times to express two distinct plastic flows. The damage D is equal to [Eb- E（εi）]/Eb, where Eb is the beginning modulus and the E（εi） is the slope of a connected line between the origin point and any other point on a tested stress-strain curve. In the new constitutive model, one Maxwell unit with low relaxation time φ is used to describe the response of anthracite to a low strain rate, while the other, with a high relaxation time φ describes the response of anthracite to a high strain rate. Simulated stress-strain curves from the new model are consistent with the measured curves.

关键词： split Hopkinson pressure bar anthracite constitutive model dynamic properties strain rate