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压缩空气小型发电系统的性能分析 被引量:2
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作者 虞启辉 韩世杰 +1 位作者 杜旭东 张旭晓 《液压与气动》 北大核心 2023年第4期87-94,共8页
为了研究压缩空气小型发电系统的性能,首先搭建试验平台并对系统各部分建立数学模型,其次基于试验平台和MATLAB/Simulink软件对系统进行试验验证和仿真研究,验证了仿真模型的合理性。进而获得不同进气压力和转速工况下发电系统的输出功... 为了研究压缩空气小型发电系统的性能,首先搭建试验平台并对系统各部分建立数学模型,其次基于试验平台和MATLAB/Simulink软件对系统进行试验验证和仿真研究,验证了仿真模型的合理性。进而获得不同进气压力和转速工况下发电系统的输出功率和效率特性。结果表明:该系统的输出功率随着进气压力的增加而增加,当系统进气压力为0.7 MPa,膨胀机输出转速为3000 r/min时,随着输出电压的增大,系统的输出功率先增加后趋于稳定,最大输出功率可达5.98 kW;不同的输出功率对应的最佳发电效率不同,当输出功率为1 kW和5 kW时,系统的发电效率分别为63.2%和76.7%;当气罐容积为500 L,储气罐初始压力为6 MPa,进气压力为0.7 MPa时,系统至多可以满足5.98 kW的输出功率工作2209 s。 展开更多
关键词 压缩空气 小型发电装置 涡轮式膨胀机 输出功率
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基于Zigbee的便携式电子呼叫系统设计 被引量:2
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作者 韩世杰 韩成浩 《吉林建筑大学学报》 CAS 2022年第3期79-83,共5页
针对冗余的排队机制无法及时取餐的问题,本文设计了一种基于Zig Bee的便携式电子呼叫铃,设计包括主动呼叫模块和被动应答模块,其中主动呼叫模块利用Zigbee无线传感网络和被动应答模块进行数据通信,在主动模块发送信号后,被动模块会蜂鸣... 针对冗余的排队机制无法及时取餐的问题,本文设计了一种基于Zig Bee的便携式电子呼叫铃,设计包括主动呼叫模块和被动应答模块,其中主动呼叫模块利用Zigbee无线传感网络和被动应答模块进行数据通信,在主动模块发送信号后,被动模块会蜂鸣、震动、LED闪烁来提醒顾客进行取餐.设计解决了排队时间长、无法及时获取取餐信息的问题,降低了商家和顾客之间的时间成本,提高了顾客消费点餐的舒适性. 展开更多
关键词 ZIGBEE 无线传感 CC2530
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Comparisons of extraction and purification methods of soil microorganism DNA from rhizosphere soil 被引量:7
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作者 JIA Xia han shi-jie +1 位作者 ZHAO Yong-hua ZHOU Yu-mei 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期31-34,共4页
Microorganism DNA of rhizosphere soil from Pinus koraiensis and Pinus sylvestriformis were extracted by proteinase K based on SDS method, CTAB method, PVP (polyvinylpolypyrrolidone) method, and freezing and thawing ... Microorganism DNA of rhizosphere soil from Pinus koraiensis and Pinus sylvestriformis were extracted by proteinase K based on SDS method, CTAB method, PVP (polyvinylpolypyrrolidone) method, and freezing and thawing method and the crude DNA from rhizosphere soil were purified by dialysis method, silver beads absorption method, and squeezing DNA gel method. The results of different extracting and purifying methods were compared and evaluated. Results indicated that the best method of extraction for microorganism DNA in rhizosphere soil was proteinse K based on SDS method with high salt concentration of 1.0% (w/v) NaCl, which could effectively eliminate humic acids and other impurities. The dialysis method was suitable to purify DNA from rhizosphere soil because of effectively removing brown matters and humic acids and the purified products were suited to PCR amplification. Squeezing DNA gel method was also a good purification method with the advantage of inexpensive in cost and efficient in use. 展开更多
关键词 EXTRACTION Microorganism DNA Pinus koraiensis Pinus sylvestriformis PURIFICATION Rhizosphere soil
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Genetic diversity and genetic differentiation of natural Pinus koraiensis population 被引量:9
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作者 FENG Fu-juan han shi-jie WANG Hong-mei 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期21-24,共4页
Genetic diversities and genetic differentiations of the four Pinus koraiensis populations (Gaofeng Forestry Farm at Tangwanghe in Yichun City, Erdaobaihe Town in the Changbai Mountains, Shcngshan Forestry Farm in Hei... Genetic diversities and genetic differentiations of the four Pinus koraiensis populations (Gaofeng Forestry Farm at Tangwanghe in Yichun City, Erdaobaihe Town in the Changbai Mountains, Shcngshan Forestry Farm in Heihe City, in China, and the suburb of Vladivostok City in Russia) were analyzed by using ISSR PCR technique. The results of 15 primers amplification showed that the ratio of polymorphic site of P koralensis population was 60.7%. Euch primer had 3.6 polymorphic sites, The diversity levels of the four P. koraiensis populations were rather higher compared with those of other Pinaceae species. The genetic diversity levels of t: koraiensis populations grown in the center region were higher than those grown in the edge zone. The genetic diversity of r3 koraiensis mainly came from the interiot of the population, accounting for 73% of total genetic diversity. There were no positive correlation between genetic distances and geographical distances for the four P koraiensis populations. The gradual decrease of natural distribution region of P. koraiensis was due to anthropic destroy and environmental factors (i.e. fire and wind throw), rather than the lower genetic diversity. 展开更多
关键词 Genetic differentiation Genetic diversity ISSR Pinus koraiensis
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基于网络药理学和分子对接探究枸杞子-菟丝子“异病同治”2型糖尿病性骨质疏松症和肾病综合征的作用机制 被引量:1
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作者 韩世杰 马桃梅 +3 位作者 王晶 马欢欢 王亚萍 王晓晖 《内蒙古中医药》 2023年第3期146-151,共6页
目的:运用网络药理学方法探讨枸杞子-菟丝子“异病同治”2型糖尿病性骨质疏松症(DOP)和肾病综合征(NS)的作用机制。方法:通过TCMSP数据库筛选枸杞子-菟丝子的主要活性成分和作用靶点,利用UniProt数据库及Perl语言进行规范以及转化为标... 目的:运用网络药理学方法探讨枸杞子-菟丝子“异病同治”2型糖尿病性骨质疏松症(DOP)和肾病综合征(NS)的作用机制。方法:通过TCMSP数据库筛选枸杞子-菟丝子的主要活性成分和作用靶点,利用UniProt数据库及Perl语言进行规范以及转化为标准基因名称,利用Cytoscape3.9.1软件构建药物-活性成分-靶点网络。通过GeneCards、OMIM及PharmGkb数据库搜集DOP和NS相关疾病靶点,将疾病靶点与药物靶点取交集,通过STRING数据库构建交集靶点的蛋白相互作用网络并筛选核心蛋白;对交集蛋白运用Rx4.1.3软件及R脚本进行GO功能富集和KEGG通路分析,运用Autodock 4.2软件进行分子对接。结果:筛选后得到枸杞子-菟丝子活性成分42个,作用靶点208个;DOP、NS疾病靶点分别为2834个、2114个,共有靶点915个,疾病和药物交集靶点86个。GO富集分析得到分子功能121条;KEGG通路富集分析获得126条信号通路,靠前的通路为糖尿病并发症中的AGE-RAGE信号通路、脂质与动脉粥样硬化信号通路、流体剪切应力与动脉粥样硬化信号通路、IL-17信号通路,主要涉及内分泌代谢、动脉粥样硬化以及炎症等。结论:枸杞子-菟丝子治疗DOP和NS具有多靶点效应,涉及多条生物过程和信号通路,调节内分泌代谢、调节动脉粥样硬化以及调控炎症反应等发挥“异病同治”作用。 展开更多
关键词 网络药理学 枸杞子-菟丝子 2型糖尿病性骨质疏松 肾病综合征 异病同治 分子对接
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Ecological functions of coarse woody debris in forest ecosystem 被引量:7
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作者 WU Jia-bing GUAN De-xin +2 位作者 han shi-jie ZhanG Mi JIN Chang-jie 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第3期247-252,共6页
Coarse woody debris is an important structure and function unit in forest ecosystem.This review analyzed the ecological functions of coarse woody debris in forest ecosystem and introduced several hotspots and existing... Coarse woody debris is an important structure and function unit in forest ecosystem.This review analyzed the ecological functions of coarse woody debris in forest ecosystem and introduced several hotspots and existing problems in coarse woody debris research field. It is suggested that quantitative research should be intensified in theintensified in the ecological demands of coarse woody debris for providing a technical guidelines in management of productivity, biodiversity and other ecologicalprocesses. 展开更多
关键词 Coarse woody debris Ecological function BIODIVERSITY DECOMPOSITION
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Carbon and Nitrogen Transformations in Surface Soils Under Ermans Birch and Dark Coniferous Forests 被引量:5
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作者 DENG Xiao-Wen han shi-jie +1 位作者 HU Yan-Ling ZHOU Yu-Mei 《Pedosphere》 SCIE CAS CSCD 2009年第2期230-237,共8页
Soil samples were taken from an Ermans birch (Betula ermanii)-dark coniferous forest (Picea jezoensis and Abies nephrolepis) ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northe... Soil samples were taken from an Ermans birch (Betula ermanii)-dark coniferous forest (Picea jezoensis and Abies nephrolepis) ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northeast China, to compare soil carbon (C) and nitrogen (N) transformations in the two forests. The soil type is Umbri-Gelic Cambosols in Chinese Soil Taxonomy. Soil samples were incubated aerobically at 20℃ and field capacity of 700 g kg^-1 over a period of 27 weeks. The amount of soil microbial biomass and net N mineralization were higher in the Ermans birch than the dark coniferous forest (P 〈 0.05), whereas the cumulative C mineralization (as CO2 emission) in the dark coniferous forest exceeded that in the Ermans birch (P 〈 0.05). Release of the cumulative dissolved organic C and dissolved organic N were greater in the Ermans birch than the dark coniferous forest (P 〈 0.05). The results suggested that differences of forest types could result in considerable change in soil C and N transformations. 展开更多
关键词 dissolved organic C dissolved organic N Ermans birch-dark coniferous forest soil C transformation soil N transformation
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洋山四期全自动集装箱码头设计创新 被引量:12
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作者 刘广红 韩时捷 +3 位作者 何继红 徐兆祥 姚宇 蔡波妮 《水运工程》 北大核心 2018年第6期189-194,共6页
自动化码头在装卸作业的稳定高效、安全节能、绿色环保等方面具有显著优势,已成为我国实现港口转型升级发展的必由之路。但我国自动化港口建设起步晚,技术经验积累少,缺少相应的技术标准和规范指导。而洋山四期工程是我国首座拥有安全... 自动化码头在装卸作业的稳定高效、安全节能、绿色环保等方面具有显著优势,已成为我国实现港口转型升级发展的必由之路。但我国自动化港口建设起步晚,技术经验积累少,缺少相应的技术标准和规范指导。而洋山四期工程是我国首座拥有安全自主技术打造的当前全球单项规模最大、技术最先进的全自动化集装箱码头工程,其设计经验对于推动我国港口的技术进步具有重要的借鉴意义。对洋山四期工程自动化集装箱码头设计所涉及的平面、工艺、结构、控制、供电、给排水等多方面设计成果进行总结和梳理,为同类工程设计提供参考。 展开更多
关键词 集装箱码头 自动化 总平面布置 轨道基础结构 数据接口 仪表远程监测 电能质量治理 节能减排 节水
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Soil and Root Respiration Under Elevated CO_2 Concentrations During Seedling Growth of Pinus sylvestris var.sylvestriformis 被引量:6
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作者 LIU Ying han shi-jie +1 位作者 ZHOU Yu-Mei LI Xue-Feng 《Pedosphere》 SCIE CAS CSCD 2007年第5期660-665,共6页
The objectives of this study were to investigate the effect of higher CO2 concentrations (500 and 700 μmol mol^-1) in atmosphere on total soil respiration and the contribution of root respiration to total soil resp... The objectives of this study were to investigate the effect of higher CO2 concentrations (500 and 700 μmol mol^-1) in atmosphere on total soil respiration and the contribution of root respiration to total soil respiration during seedling growth of Pinus sylvestris vat. sylvestriformis. During the four growing seasons (May-October) from 1999 to 2003, the seedlings were exposed to elevated concentrations of CO2 in open-top chambers. The total soil respiration and contribution of root respiration were measured using an LI-6400-09 soil CO2 flux chamber on June 15 and October 8, 2003. To separate root respiration from total soil respiration, three PVC cylinders were inserted approximately 30 cm deep into the soil in each chamber. There were marked diurnal changes in air and soil temperatures on June 15. Both the total soil respiration and the soil respiration without roots showed a strong diurnal pattern, increasing from before sunrise to about 14:00 in the afternoon and then decreasing before the next sunrise. No increase in the mean total soil respiration and mean soil respiration with roots severed was observed under the elevated CO2 treatments on June 15, 2003, as compared to the open field and control chamber with ambient CO2. However, on October 8, 2003, the total soil respiration and soil respiration with roots severed in the open field were lower than those in the control and elevated CO2 chambers. The mean contribution of root respiration measured on June 15, 2003, ranged from 8.3% to 30.5% and on October 8, 2003, from 20.6% to 48.6%. 展开更多
关键词 contribution of root respiration elevated CO2 concentration total soil respiration
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低NO_(x)环境异戊二烯促进甲苯生成甲基丁烯二醛的模拟实验 被引量:2
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作者 张扬 韩士杰 +5 位作者 李勤勤 王文路 肖扬 郭严 王好 王伯光 《中国环境科学》 EI CAS CSCD 北大核心 2022年第9期4001-4008,共8页
在低NO_(x)浓度条件下开展甲苯和异戊二烯复合体系的烟雾箱模拟实验,使用高时间分辨率的在线质子转移反应飞行时间质谱(PTR-TOF-MS)实时监测混合体系中反应物与产物的浓度变化情况,探究人为源与天然源交汇过程中,自然源挥发性有机物(BVO... 在低NO_(x)浓度条件下开展甲苯和异戊二烯复合体系的烟雾箱模拟实验,使用高时间分辨率的在线质子转移反应飞行时间质谱(PTR-TOF-MS)实时监测混合体系中反应物与产物的浓度变化情况,探究人为源与天然源交汇过程中,自然源挥发性有机物(BVOCs)对人为挥发性有机物(AVOCs)化学降解的影响.结果表明,异戊二烯与甲苯竞争OH自由基,从而抑制了甲苯的化学降解,该竞争反应开始得越早,抑制效果越显著.研究还发现异戊二烯会增强甲苯RO_(2)降解途径产物的产量,生成更多1,4不饱和-二羰基化合物(如丁烯二醛和甲基丁烯二醛)与二羰基化合物(如乙二醛和甲基乙二醛),其中甲基丁烯二醛增量最高可达38.6%.此外,异戊二烯快速氧化生成的RO_(2)自由基碳数更少,可能与甲苯氧化生成的RO_(2)自由基发生了快速的交叉反应,有利于甲苯RO自由基的生成及裂解,最终导致甲苯RO_(2)途径裂解产物的增加. 展开更多
关键词 甲苯 异戊二烯 烟雾箱模拟 人为源-天然源交汇作用 RO_(2)途径 甲基丁烯二醛 挥发性有机物
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Relationship between diversity of forest plant species and environmental gradient in eastern mountainous area of Heilongjiang Province, China 被引量:2
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作者 WANG Qing-gui XING Ya-juan +1 位作者 ZHOU Xiao-feng han shi-jie 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期252-254,共3页
Twenty-three secondary forest communities with different structure were selected in Mao'er Mountain National Park of Heilongjiang Province, China to study the relationship between diversity of forest plant species an... Twenty-three secondary forest communities with different structure were selected in Mao'er Mountain National Park of Heilongjiang Province, China to study the relationship between diversity of forest plant species and environmental gradient. The forest plant species diversity was analyzed by the diversity index, and the environmental factors was quantified by the method of Whittaker's quantification of environmental gradient. Meanwhile, β-diversity indexes of communities were calculated with similar measurements. The results showed that the Shannon-wiener diversity index of forest plant species increased with the increase of the environmental gradient, and the β-diversity indexes of communities showed a liner increase along with the change of environmental gradient. 展开更多
关键词 Species diversity Forest plant species Heilongjiang Province Shannon-wiener diversity β-diversity index Environmental gradient
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Responses of soil microorganisms to elevated CO2 in experiment sites of Pinus sylvestriformis and Pinus koraiensis 被引量:2
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作者 JIA Xia han shi-jie ZHOU Yu-mei 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第3期219-222,共4页
Responses of soil microbial activities to elevated CO, in experiment sites of Pinus sylvestriformis and Pinus koratensts seecllmgs were studied in summer in 2003. The results indicated the number of bacteria decreased... Responses of soil microbial activities to elevated CO, in experiment sites of Pinus sylvestriformis and Pinus koratensts seecllmgs were studied in summer in 2003. The results indicated the number of bacteria decreased significantly (p 〈 0.05) under elevated CO, for Pinus syivestriformis and Pinups koraiensis. Amylase and invertase activities in soil increased for Pinus syivestriformis and decreased for Pinus koraiensis with CO2 enrichment compared with those at ambient (350 pmol·mol^-1). The size of microbial biomass C also decreased significantly at 700 μmol- mol^-1 CO2. Bacterial community structure had some evident changes under elevated CO, by DGGE (Denaturing Gradient Gel Electrophoresis) analysis of bacterial 16S rDNA gene fragments amplified by PCR from DNA extracted directly from soil. The results suggested that responses of soil microorganisms to elevated CO2 would be related to plant species exposed to elevated CO2. 展开更多
关键词 Bacterial community Bacterial numbers Elevated CO2 Soil enzyme activity.
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Relationship between diversity of forest plant and community dynamics in eastern mountain area of Heilongjiang Province, China 被引量:1
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作者 WANG Qing-gui XING Ya-juan +1 位作者 ZHOU Xiao-feng han shi-jie 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期289-292,共4页
The biodiversity was studied in 26 communities with different structures in Maoershan National Park and Liangshui Natural Reserve of Northeast Forestry University in Heilongjiang Province, China. Composition index (C... The biodiversity was studied in 26 communities with different structures in Maoershan National Park and Liangshui Natural Reserve of Northeast Forestry University in Heilongjiang Province, China. Composition index (CI) was taken as a parameter to quantify the community dynamics, which can nicely describe forest community dynamics, meanwhile, the relationship between diversity and community dynamics were also investigated and analyzed. Results showed that the total number species of community, richness, evenness, and Shannon-Wiener diversity index were obviously different in every community. The richness decreased with the increasing CI of every community, which means richness was in inverse proportion to community dynamics. The Shannon-Wiener index of every community increased from the initial stage to the middle stage of succession, and then decreased in the climax stage. The coverage weighted foliage-height diversity index increased along with the increase of CI, which was similar as the oattem diversity. 展开更多
关键词 Eastern mountain area of Heilongjiang province Shannon-wiener diversity Pattern diversity Community dynamics
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新型可调轨枕可靠性研究及应用 被引量:1
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作者 王施恩 韩时捷 马哲超 《水运工程》 北大核心 2018年第3期185-189,共5页
新型可调轨枕是一种可进行高精度及高效率调整的轨枕结构。轨枕本体结构内设置了预埋钢板、套管及螺母,通过连接螺栓与上部可调支座连接,后续可在轨枕本体与可调支座间插入调节钢板以达到快速调节不均匀沉降的目的。但其由于增设了预埋... 新型可调轨枕是一种可进行高精度及高效率调整的轨枕结构。轨枕本体结构内设置了预埋钢板、套管及螺母,通过连接螺栓与上部可调支座连接,后续可在轨枕本体与可调支座间插入调节钢板以达到快速调节不均匀沉降的目的。但其由于增设了预埋套管及连接螺栓,其结构的承载能力、疲劳耐久性以及螺栓抗拔力是否可满足重载机械高频率的使用要求需要进一步研究。通过相关试验研究,对该新型轨枕的可靠性进行验证。 展开更多
关键词 新型可调轨枕 承载能力 疲劳耐久性 抗拔力
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中性点非有效接地配电网弧光接地的物理模拟研究 被引量:2
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作者 韩士杰 张凤鸽 +2 位作者 黎涛 袁莉 杨德先 《自动化技术与应用》 2023年第10期137-140,共4页
弧光接地是中性点不接地配电网中最常见的故障,对电网设备的绝缘性能有严重威胁,从而影响电网运行的稳定性,亟需进行弧光接地故障研究。研究提出弧光接地的物理模拟方法,设计实现弧光模拟装置,通过精确控制放电间隙及放电极移动速度,实... 弧光接地是中性点不接地配电网中最常见的故障,对电网设备的绝缘性能有严重威胁,从而影响电网运行的稳定性,亟需进行弧光接地故障研究。研究提出弧光接地的物理模拟方法,设计实现弧光模拟装置,通过精确控制放电间隙及放电极移动速度,实现稳定模拟的电弧接地、间歇性电弧接地、弧光渐变等各种弧光接地现象。记录试验波形,并进行分析波形,发现弧光放电的规律。结果表明,物理模拟方法能够可控模拟弧光现象,记录下的波形数据可为处理弧光接地故障提供参考。 展开更多
关键词 中性点不接地 弧光接地 物理模拟 波形分析 燃弧电压
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发电机采用数模混合仿真的微型动模试验系统
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作者 韩士杰 张凤鸽 +3 位作者 杨德先 郭春耀 杨洪涛 李卫良 《电工电气》 2021年第12期48-52,共5页
基于当前动模、数字仿真遇到的问题,搭建了基于数模混合发电机的微型动模试验系统。数字、物理混合仿真的发电机采用了功率在环技术,结合了物理仿真和实时数字仿真的优点,更接近现实的试验,实时运算可反复修改,减少测试验证周期。发电... 基于当前动模、数字仿真遇到的问题,搭建了基于数模混合发电机的微型动模试验系统。数字、物理混合仿真的发电机采用了功率在环技术,结合了物理仿真和实时数字仿真的优点,更接近现实的试验,实时运算可反复修改,减少测试验证周期。发电机采用数模混合仿真的微型动模试验系统,可实现电力系统的低电压、小电流、微功率的物理模拟,减少了测试准备时间、验证周期和测试成本,有效提高了电力系统仿真建模、验证研究的技术水平。 展开更多
关键词 数模混合 发电机 电力系统 仿真技术 试验系统 微型动模
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柴胡引种试验研究
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作者 韩世杰 屈亮 乔青萍 《现代农业科技》 2020年第16期60-61,63,共3页
为了筛选出适宜山西太谷地区引种种植的柴胡品种,利用旱作栽培技术引进11个不同产地的柴胡品种,研究其原产地和引种地的生态条件、引种后出苗期和营养生长期等.结果表明,太谷地区春旱和夏旱严重,左权柴胡虽发生叶片萎蔫现象但未旱死,抗... 为了筛选出适宜山西太谷地区引种种植的柴胡品种,利用旱作栽培技术引进11个不同产地的柴胡品种,研究其原产地和引种地的生态条件、引种后出苗期和营养生长期等.结果表明,太谷地区春旱和夏旱严重,左权柴胡虽发生叶片萎蔫现象但未旱死,抗旱性能很好,是一个抗旱良种;营养生长期持续时间是影响良种选育的一个重要因素,左权柴胡营养生长时期较红柴胡和三岛柴胡长,有利于高产.综合可知,左权柴胡适宜太谷地区引种种植. 展开更多
关键词 柴胡 引种 出苗期 生育期
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Distribution of Soil Organic Carbon Fractions Along the Altitudinal Gradient in Changbai Mountain,China 被引量:44
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作者 ZhanG Min ZhanG Xiao-Ke +4 位作者 LIANG Wen-Ju JIANG Yong DAI Guan-Hua WANG Xu-Gao han shi-jie 《Pedosphere》 SCIE CAS CSCD 2011年第5期615-620,共6页
Understanding the responses of soil organic carbon(SOC) fractions to altitudinal gradient variation is important for understanding changes in the carbon balance of forest ecosystems.In our study the SOC and its fracti... Understanding the responses of soil organic carbon(SOC) fractions to altitudinal gradient variation is important for understanding changes in the carbon balance of forest ecosystems.In our study the SOC and its fractions of readily oxidizable carbon(ROC),water-soluble carbon(WSC) and microbial biomass carbon(MBC) in the soil organic and mineral horizons were investigated for four typical forest types,including mixed coniferous broad-leaved forest(MCB),dark coniferous spruce-fir forest(DCSF),dark coniferous spruce forest(DCS),and Ermans birch forest(EB),along an altitudinal gradient in the Changbai Mountain Nature Reserve in Northeast China.The results showed that there was no obvious altitudinal pattern in the SOC.Similar variation trends of SOC with altitude were observed between the organic and mineral horizons.Significant differences in the contents of SOC,WSC,MBC and ROC were found among the four forest types and between horizons.The contents of ROC in the mineral horizon,WSC in the organic horizon and MBC in both horizons in the MCB and EB forests were significantly greater than those in either DCSF or DCS forest.The proportion of soil WSC to SOC was the lowest among the three main fractions.The contents of WSC,MBC and ROC were significantly correlated(P < 0.05) with SOC content.It can be concluded that vegetation types and climate were crucial factors in regulating the distribution of soil organic carbon fractions in Changbai Mountain. 展开更多
关键词 active carbon fractions ALTITUDE forest ecosystem Northeast China vegetation type
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郑州市PM2.5中水溶性离子特征及来源分析 被引量:61
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作者 杨留明 王申博 +5 位作者 郝祺 韩士杰 李晨 赵庆炎 燕启社 张瑞芹 《环境科学》 EI CAS CSCD 北大核心 2019年第7期2977-2984,共8页
为探究郑州市PM2.5中水溶性离子污染特征,本研究自2017年12月1日至2018年11月30日对郑州市PM2.5中水溶性离子进行为期1a的高时间分辨率持续观测,并基于高时间分辨率观测数据分析水溶性离子特征并对其进行来源分析.结果表明,观测期间郑... 为探究郑州市PM2.5中水溶性离子污染特征,本研究自2017年12月1日至2018年11月30日对郑州市PM2.5中水溶性离子进行为期1a的高时间分辨率持续观测,并基于高时间分辨率观测数据分析水溶性离子特征并对其进行来源分析.结果表明,观测期间郑州市总水溶性离子平均质量浓度为42.7μg·m^-3,各离子质量浓度从大到小分别为:硝酸根(17.7μg·m^-3)、硫酸根(10.2μg·m^-3)、铵根(9.0μg·m^-3)、氯离子(2.3μg·m^-3)、钾离子(1.3μg·m^-3)、钠离子(1.3μg·m^-3)、钙离子(0.8μg·m^-3)和镁离子(0.1μg·m^-3).总水溶性离子质量浓度表现为冬季最高,秋季略高于春季,夏季最低的季节特征,在PM2.5中的占比表现为秋季(65.2%)>冬季(52.5%)>夏季(48.2%)>春季(43.0%).除钠离子和钙离子外,其余水溶性离子质量浓度均表现为冬季>秋季>春季>夏季的季节变化特征,而钠离子表现为秋季最高,夏季最低的季节变化特征,钙离子表现为秋季最高,冬季最低的季节变化特征.总水溶性离子质量浓度全年及春季、夏季和秋季均表现为单峰分布的日变化特征,冬季没有显著的日变化特征.观测期间二次离子(硫酸根、硝酸根和铵根)质量浓度占PM2.5的43.8%,是PM2.5的重要组成部分,主要以(NH4)2SO4和NH4NO3的形式存在.观测期间郑州市存在较大程度的二次转化过程,且相对湿度对硫氧化率的影响较大,而温度对氮氧化率的影响较大.观测期间二次离子间具有较好的相关性,钾离子与镁离子和氯离子也表现出较好的相关性.硝酸根、硫酸根和铵根的主要来源是气体污染物的二次转化,镁离子和钙离子通常来源于土壤尘和建筑尘,钾离子是主要的生物质燃烧标识物之一,钠离子来自于海盐和土壤尘,氯离子不仅来自于海盐,也可来自生物质燃烧和化石燃料燃烧.主成分分析结果表明观测期间郑州市PM2.5中水溶性离子主要受二次转化、燃烧源及土壤或建筑扬尘源排放影响. 展开更多
关键词 在线 PM2.5 水溶性离子 季节变化 二次转化 来源解析
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中国东北兴安落叶松林空间分布及其对气候变化的响应 被引量:13
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作者 张喜娟 陈琛 +4 位作者 郜飞飞 原树生 韩士杰 倪震东 于景华 《生态学杂志》 CAS CSCD 北大核心 2022年第6期1041-1049,共9页
气候变化直接影响着植被地理分布。兴安落叶松林主要分布于中国东北的大、小兴安岭林区,地处北方针叶林南缘,对水热条件变化极为敏感。本文利用MAXENT模型模拟兴安落叶松林空间分布现状、不同排放情景(RCP2.6、RCP4.5和RCP8.5)下2050s和... 气候变化直接影响着植被地理分布。兴安落叶松林主要分布于中国东北的大、小兴安岭林区,地处北方针叶林南缘,对水热条件变化极为敏感。本文利用MAXENT模型模拟兴安落叶松林空间分布现状、不同排放情景(RCP2.6、RCP4.5和RCP8.5)下2050s和2070s的潜在空间分布以及其适生区对气候变化的响应。结果表明:对兴安落叶松林地理分布起主要贡献的环境因子包括温度年度范围、坡向、温度季节性变化、最干燥季度的平均温度、最冷月份的最低温度,5个因子的累积贡献率达83.80%;兴安落叶松林主要分布在黑龙江省大兴安岭地区和内蒙古呼伦贝尔市东北部(即大兴安岭国有林区),以及黑龙江省黑河市和伊春市(即小兴安岭国有重点林区的中北部);无论哪种未来气候情景,兴安落叶松林在2050年和2070年新增适生区较少,大兴安岭东麓、小兴安岭适生区面积下降较多,适生区丧失率为15.06%~38.87%,下降区域主要为黑龙江省黑河市和伊春市。应用多分类Logistic回归方法探讨了兴安落叶松林空间分布对气候变化的响应,结果表明,温度季节性变化的降低、降水量的季节变化的降低、最干燥季降水的升高、最暖月最高温度的升高是兴安落叶松林适生区缩小的主要原因。 展开更多
关键词 兴安落叶松林 MAXENT 空间格局 气候变化
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