期刊文献+
共找到1,579篇文章
< 1 2 79 >
每页显示 20 50 100
TCbHP在老年HER-2阳性乳腺癌患者新辅助化疗中的应用效果
1
作者 王禾 方琦 王秀 《中外医学研究》 2024年第18期129-132,共4页
目的:研究TCbHP在老年HER-2阳性乳腺癌患者新辅助化疗中的应用效果。方法:选取2020年3月—2022年4月苏州大学附属第三医院收治的100例老年HER-2阳性乳腺癌患者,随机将其分为对照组(n=50)和观察组(n=50)。对照组给予THP新辅助化疗,观察... 目的:研究TCbHP在老年HER-2阳性乳腺癌患者新辅助化疗中的应用效果。方法:选取2020年3月—2022年4月苏州大学附属第三医院收治的100例老年HER-2阳性乳腺癌患者,随机将其分为对照组(n=50)和观察组(n=50)。对照组给予THP新辅助化疗,观察组给予TCbHP新辅助化疗。比较两组临床疗效、治疗前后肿瘤标志物及不良反应。结果:观察组客观缓解率高于对照组,差异有统计学意义(P<0.05)。治疗后,两组癌胚抗原与糖类抗原125水平均低于治疗前,观察组癌胚抗原与糖类抗原125水平均低于对照组,差异有统计学意义(P<0.05)。两组血小板减少、肝损伤、脱发、恶心呕吐、手足综合征发生率比较,差异无统计学意义(P>0.05)。结论:相比THP,TCbHP可进一步抑制老年HER-2阳性乳腺癌患者肿瘤标志物表达,有效控制疾病发展,不会加重化疗引起的不良反应。 展开更多
关键词 人表皮生长因子受体-2阳性 单抗 新辅助化疗 紫杉醇 乳腺癌
下载PDF
Responses of runoff to changes in climate and human activities in the Liuhe River Basin, China
2
作者 LI Mingqian wang he +3 位作者 DU Wei GU Hongbiao ZHOU Fanchao CHI Baoming 《Journal of Arid Land》 SCIE CSCD 2024年第8期1023-1043,共21页
Since the 1950s,numerous soil and water conservation measures have been implemented to control severe soil erosion in the Liuhe River Basin(LRB),China.While these measures have protected the upstream soil and water ec... Since the 1950s,numerous soil and water conservation measures have been implemented to control severe soil erosion in the Liuhe River Basin(LRB),China.While these measures have protected the upstream soil and water ecological environment,they have led to a sharp reduction in the downstream flow and the deterioration of the river ecological environment.Therefore,it is important to evaluate the impact of soil and water conservation measures on hydrological processes to assess long-term runoff changes.Using the Soil and Water Assessment Tool(SWAT)models and sensitivity analyses based on the Budyko hypothesis,this study quantitatively evaluated the effects of climate change,direct water withdrawal,and soil and water conservation measures on runoff in the LRB during different periods,including different responses to runoff discharge,hydrological regime,and flood processes.The runoff series were divided into a baseline period(1956-1969)and two altered periods,i.e.,period 1(1970-1999)and period 2(2000-2020).Human activities were the main cause of the decrease in runoff during the altered periods,contributing 86.03%(-29.61 mm),while the contribution of climate change was only 13.70%(-4.70 mm).The impact of climate change manifests as a decrease in flood volume caused by a reduction in precipitation during the flood season.Analysis of two flood cases indicated a 66.00%-84.00%reduction in basin runoff capacity due to soil and water conservation measures in the upstream area.Soil and water conservation measures reduced the peak flow and total flood volume in the upstream runoff area by 77.98%and 55.16%,respectively,even with nearly double the precipitation.The runoff coefficient in the reservoir area without soil and water conservation measures was 4.0 times that in the conservation area.These results contribute to the re-evaluation of soil and water conservation hydrological effects and provide important guidance for water resource planning and water conservation policy formulation in the LRB. 展开更多
关键词 RUNOFF soil and water conservation climate variability FLOOD human activities Liuhe River Basin
下载PDF
上皮间质转换标志物在胃癌中的表达及与Her-2的关系 被引量:2
3
作者 王贺 申志华 +2 位作者 薛润国 刘海丽 谢静 《河北医学》 CAS 2021年第10期1608-1612,共5页
目的:观察在胃癌中E-cadherin和Vimentin这两种上皮间质转化(epithelial-mesenchymal transition,EMT)标记物和Her-2的表达情况,分析EMT与胃癌临床病理特征的关系及与Her-2表达的关系。方法:采用免疫组化检测EMT标记物E-cadherin和Vimen... 目的:观察在胃癌中E-cadherin和Vimentin这两种上皮间质转化(epithelial-mesenchymal transition,EMT)标记物和Her-2的表达情况,分析EMT与胃癌临床病理特征的关系及与Her-2表达的关系。方法:采用免疫组化检测EMT标记物E-cadherin和Vimentin在198例胃癌中的表达情况;同时检测胃癌中Her-2的表达情况与EMT之间的关系。结果:胃癌中Vimentin表达高于癌旁组织,E-cadherin表达低于癌旁组织,差异具有统计学意义(P<0.05);E-cadherin和Vimentin的表达与年龄、性别无关(P>0.05);E-cadherin和Vimentin的表达与肿瘤分化程度、浸润深度及是否有淋巴结转移有关(P<0.05);Vimentin在Her-2阳性的胃癌组织中的表达高于Her-2阴性的组织,而E-cadherin在Her-2阳性的胃癌组织中的表达低于Her-2阴性的组织,差异具有统计学意义(P<0.05)。结论:EMT现象在胃癌的发生、发展过程中发挥作用;在胃癌中,Her-2的表达对EMT标志物表达有所影响。 展开更多
关键词 上皮间质转换 胃癌 人表皮生长因子2
下载PDF
High Expression of hsMAD2 in the Villi of Spontaneously Aborted Embryo with Chromosomal Abnormality
4
作者 Zaochang wang Junjie Hu +4 位作者 wang he Humin Gong Weihua Xu Zhichao Ma Xinping Chen 《Open Journal of Obstetrics and Gynecology》 2021年第6期763-772,共10页
<strong>Objective</strong><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><strong>:</strong... <strong>Objective</strong><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><strong>:</strong></span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> To investigate the changes of hsMAD2 protein and gene expression levels during chromosome segregation of human embryos. </span><b><span style="font-family:Verdana;">Method</span></b></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">:</span></b></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> The embryos of spontaneous abortion were collected in our hospital from 2009 to 2013, the chromosomal numbers of the embryonic villi were subsequently detected by fluorescence in situ hybridization (FISH). The patients were then divided into the normal and abnormal groups based on the chromosome number. The hsMAD2 protein and gene expression levels in the villi tissues of the two embryo groups were detected by western blotting and qRT-PCR, respectively. The hsMAD2 protein and gene levels in the embryonic villus tissue of the patient were detected. </span><b><span style="font-family:Verdana;">Results</span></b></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">:</span></b></span></span><span><span><b><span style="font-family:""> </span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">From 2009 to 2013, we collected 50 embryos from spontaneous abortion patients. The chromosome abnormality and no abnormality were 36 cases (abnormal number of 28 cases (56.0%) and chimerism in 8 cases (16.0%)) and 14 cases (28.0%), respectively.</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">The expression of hsmad2 protein and its gene in the villi of spontaneously aborted embryo with chromosomal abnormality in the abnormal group was significantly higher than that in those without chromosomal abnormalities (0.88 ± 0.20 vs 0.61 ± 0.19, P < 0.05), (23.46 ± 0.07 vs 18.35 ± 0.10, P < 0.05).</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">Conclusion</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><b><span style="font-family:Verdana;">:</span></b></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> Abnormal number of chromosomes is closely related to spontaneous abortion Linked, hsMAD2 factor has a card effect on the cell cycle, can block the mitotic process of cells, and play an important role in maintaining the normal separation and stability of chromosomes</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span> 展开更多
关键词 Spontaneous Abortion Embryonic Villi Chromosomal Abnormality hsMAD2
下载PDF
QuEChERS-表面增强拉曼光谱法测定花生中黄曲霉毒素B_(1) 被引量:2
5
作者 王宇龙 翟文磊 +3 位作者 韩晨瑞 王荷 赵志磊 王蒙 《食品安全质量检测学报》 CAS 北大核心 2022年第5期1502-1508,共7页
目的建立基于QuEChERS净化和表面增强拉曼光谱法(surface-enhanced Raman spectroscopy,SERS)测定花生中黄曲霉毒素B_(1)(aflatoxin B_(1),AFB_(1))的分析方法。方法以纳米银(nano silver,AgNPs)作为SERS活性基底,结合QuEChERS样品预处... 目的建立基于QuEChERS净化和表面增强拉曼光谱法(surface-enhanced Raman spectroscopy,SERS)测定花生中黄曲霉毒素B_(1)(aflatoxin B_(1),AFB_(1))的分析方法。方法以纳米银(nano silver,AgNPs)作为SERS活性基底,结合QuEChERS样品预处理技术和基于SERS特征峰的非标记检测方法测定花生中的AFB_(1),考察凝聚剂种类与浓度、纳米银与样品的比例以及净化剂种类与浓度等条件对实验结果的影响。结果在凝聚剂KBr浓度为1.2 mol/L、净化剂类石墨相氮化碳质量浓度为10.0 mg/mL、沸石咪唑酯骨架-67质量浓度为2.5 mg/mL时,AFB_(1)的检出限为1ng/mL,线性范围为1~200ng/mL,相关系数(r^(2))为0.99377,平均回收率为98.0%~104.6%,相对标准偏差为0.73%~3.79%。结论本研究建立的方法简单、快速且准确,可用于花生中AFB_(1)污染的快速检测。 展开更多
关键词 黄曲霉毒素B_(1) 表面增强拉曼光谱法 QUECHERS 花生
下载PDF
煤矿智能快速掘进关键技术研究现状及展望 被引量:6
6
作者 毛君 杨润坤 +4 位作者 谢苗 卢进南 王贺 刘治翔 王帅 《煤炭学报》 EI CAS CSCD 北大核心 2024年第2期1214-1229,共16页
针对煤矿巷道掘进智能化建设情况,探讨了现阶段分别以连采机、掘锚一体机、全断面掘进系统、掘锚机为核心的四大类智能快速掘进成套装备发展现状,分析了四大类智能快掘装备与地质条件适用性,提出了实现煤矿智能化掘进需要解决的关键技... 针对煤矿巷道掘进智能化建设情况,探讨了现阶段分别以连采机、掘锚一体机、全断面掘进系统、掘锚机为核心的四大类智能快速掘进成套装备发展现状,分析了四大类智能快掘装备与地质条件适用性,提出了实现煤矿智能化掘进需要解决的关键技术的问题,探讨了以信息传输与智能分析技术、智能感知技术、精确定位导航技术,自主定型定向截割技术、掘进机远程自主截割控制技术以及多级多工序智能协同控制技术为基础的智能化掘进实现途径;基于复杂地质条件下煤矿巷道掘进亟待解决的关键问题,提出了以掘进作业功能需求、掘进工艺要求为依据的系统化分析、模块化设计、功能优化组合的设计方法;研究了以虚控实、虚实结合的多级数字孪生构架,基于掘进巷道设备、环境、地质构造多维信息再现实现掘进机远程控制;提出了单机智能化、系统协同化、井下智控与地面远程监控相协同的控制方法。开发了新型的无重复碾压柔性超前支护技术、截割部多级伸缩截割技术、智能锚固机组多钻机并行作业等技术,研制了具有掘、支、锚、运、探多工序并行作业的新型快速掘进作业联合机组,提出了掘进机器人、超前支护机器人、锚固机器人、辅助运输机器人组柔性并行作业技术;提出了基于数据驱动的多机多工序协同控制行为规划决策方法。提出构建完整的煤矿井下跨系统全时空信息数字感知体系,构建集井下现场生产状态、掘进巷道空间信息、掘进装备状态、风险信息等多参量、多尺度、全时空特性的数据感知智能化监控平台,实现虚拟系统与实际掘进系统实时通信,通过数据驱动规划分析实现智能化、少人化掘进。 展开更多
关键词 智能掘进 自主定性定向截割 柔性并行作业 多级多工序协同控制 数字孪生
下载PDF
The validation of the significant wave height product of HY-2altimeter–primary results 被引量:7
7
作者 CheN Chuntao ZHU Jianhua +5 位作者 LIN Mingsen ZHAO Yili HUANG Xiaoqi wang he ZHANG Youguang PENG Hailong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第11期82-86,共5页
The HY-2 satellite was successfully launched on 16 August 2011. The HY-2 significant wave height (SWH) is validated by the data from the South China Sea (SCS) field experiment, National Data Buoy Center (NDBC/ bu... The HY-2 satellite was successfully launched on 16 August 2011. The HY-2 significant wave height (SWH) is validated by the data from the South China Sea (SCS) field experiment, National Data Buoy Center (NDBC/ buoys and Jason-1/2 altimeters, and is corrected using a linear regression with in-situ measurements. Com- pared with NDBC SWH, the HY-2 SWH show a RMS of 0.36 m, which is similar to Jason- 1 and Jason-2 SWH with the RMS of 0.35 m and 0.37 m respectively; the RMS of corrected HY-2 SWH is 0.27 m, similar to 0.27 m and 0.23 m of corrected Jason-1 and Jason-2 SWH. Therefore the accuracy of HY-2 SWH products is close to that of Jason-1/2 SWH, and the linear regression function derived can improve the accuracy of HY-2 SWH products. 展开更多
关键词 ALTIMETER significant wave height VALIDATION linear regression CORRECTION root mean square
下载PDF
三维地籍测绘研究及其标准化探索 被引量:2
8
作者 徐洪秀 杨玉忠 +2 位作者 王赫 吴洪涛 谭新宇 《测绘通报》 CSCD 北大核心 2024年第1期136-140,共5页
针对传统的基于二维地籍的土地管理模式不能很好地满足日趋紧张的城市空间管理需求的问题,本文首先分析三维地籍国内外发展现状,提出了基于三维地籍测绘解决土地立体化管理难点、痛点的技术路线,然后开展了三维地籍标准化探索,重点介绍... 针对传统的基于二维地籍的土地管理模式不能很好地满足日趋紧张的城市空间管理需求的问题,本文首先分析三维地籍国内外发展现状,提出了基于三维地籍测绘解决土地立体化管理难点、痛点的技术路线,然后开展了三维地籍标准化探索,重点介绍《三维地籍产权体测绘技术规程》的编制过程和主要内容,并将研究路线及此标准应用到典型案例中,以证明该技术路线的可行性和标准的适用性。 展开更多
关键词 三维地籍 三维产权体 测绘 标准化
下载PDF
急性心肌梗死合并心原性休克患者器械辅助支持下直接经皮冠状动脉介入治疗预后不良的因素分析 被引量:1
9
作者 罗明华 陈玉善 +6 位作者 王贺 关怀敏 解金红 邱承杰 宗永华 尚莎莎 王运蔚 《中国介入心脏病学杂志》 CSCD 2024年第4期197-202,共6页
目的本研究旨在考察急性心肌梗死合并心原性休克患者直接经皮冠状动脉介入治疗(PPCI)术后预后不良的影响因素。方法入选2015年1月至2019年12月期间,河南中医药大学第一附属医院胸痛中心收治急性心肌梗死合并心原性休克并且行PPCI的患者... 目的本研究旨在考察急性心肌梗死合并心原性休克患者直接经皮冠状动脉介入治疗(PPCI)术后预后不良的影响因素。方法入选2015年1月至2019年12月期间,河南中医药大学第一附属医院胸痛中心收治急性心肌梗死合并心原性休克并且行PPCI的患者,收集其临床基线特征、冠状动脉造影及PPCI相关参数、器械辅助支持信息等。根据1年内随访生存与否,分为生存组与死亡组,比较两组各项因素。结果共入选40例患者,其中生存组26例,死亡组14例。两组在基线资料、入院诊断、危险因素及合并症等方面差异均无统计学意义(均P>0.05);生存组较死亡组有入院时心率较低、血压较高的趋势;生存组心肌酶显著低于死亡组(肌酸激酶峰值:496.00(198.25,2830.00)U/L比3040.00(405.75,5626.53)U/L,P=0.003;肌酸激酶同工酶MB型峰值:52.65(31.75,219.50)U/L比306.00(27.25,489.63)U/L,P=0.006);两组间在冠状动脉造影及PPCI相关指标方面比较,生存组较对照组有更高的完全血运重建率(53.85%比21.43%,P=0.048);两组器械辅助支持方面比较,生存组较死亡组有更多的体外膜肺氧合(ECMO)联合主动脉内球囊反搏(IABP)支持的比例(38.46%比7.14%,P=0.034)。结论急性心肌梗死合并心原性休克行PPCI的患者的预后与心肌酶水平、ECMO联合IABP支持以及完全血运重建有关。 展开更多
关键词 急性心肌梗死 心原性休克 预后 直接经皮冠状动脉介入治疗 心肌酶 体外膜肺氧合 主动脉内球囊反搏
下载PDF
公立医院行风建设指数定量评价体系构建研究 被引量:1
10
作者 桂德权 毕欣然 +4 位作者 蔡志玲 陈政 易丽叶 王熇 徐琨 《中国医院》 北大核心 2024年第3期40-43,共4页
目的:从医院管理视角引入指数定量评价体系,用形象、具体且高度凝练的指标和评价要点来描述公立医院的行风建设工作。方法:立足当前公立医院行风建设管理中重点督查的关键领域,围绕落实主体责任、完善制度建设等5个维度,设计定量与定性... 目的:从医院管理视角引入指数定量评价体系,用形象、具体且高度凝练的指标和评价要点来描述公立医院的行风建设工作。方法:立足当前公立医院行风建设管理中重点督查的关键领域,围绕落实主体责任、完善制度建设等5个维度,设计定量与定性相结合的行风建设指数评价模式。结果:构建了适用于公立医院临床科室的数字化行风建设指数评价机制,划定评价周期并实行动态管理,实现对行风建设发展问题的精准定位和对行风监督工作具体实施情况的有效全面评估。结论:本研究客观评价医德医风水平和医院行风建设管理现状,有助于综合理解和客观评估复杂的管理行为,为未来数字医院的横向管理与纵向规划提供了有效的战略改进支撑,有助于推动现代化医院行风治理的标准化、精细化和信息化发展。 展开更多
关键词 公立医院 行风建设 数字化治理 精细化管理 定量评价
下载PDF
含静止无功发生器的直驱风电并网系统稳定性分析及振荡抑制策略 被引量:2
11
作者 张芳 王赫 李传栋 《电力自动化设备》 EI CSCD 北大核心 2024年第6期1-8,17,共9页
风电并网系统稳定性分析及振荡抑制策略大多集中于风电场本身,针对含静止无功发生器(SVG)的直驱风电并网系统研究较少。基于特征值灵敏度筛选出对含SVG的直驱风电并网系统稳定性较显著的控制通道,然后基于独立通道分析设计理论将并网系... 风电并网系统稳定性分析及振荡抑制策略大多集中于风电场本身,针对含静止无功发生器(SVG)的直驱风电并网系统研究较少。基于特征值灵敏度筛选出对含SVG的直驱风电并网系统稳定性较显著的控制通道,然后基于独立通道分析设计理论将并网系统由多输入多输出耦合系统等效拆分为多个单输入单输出控制通道,在定性分析并网系统稳定性的同时定量评估不同控制通道间的交互作用程度。为抑制控制通道间的交互作用,提出了基于H∞鲁棒控制的次同步振荡抑制策略。通过电磁暂态仿真,验证了基于独立通道分析设计理论分析并网系统稳定性的正确性以及基于H∞鲁棒控制的次同步振荡抑制策略的有效性。 展开更多
关键词 直驱风电机组 静止无功发生器 独立通道 H∞鲁棒控制 振荡抑制
下载PDF
A semiempirical algorithm for SAR wave height retrieval and its validation using Envisat ASAR wave mode data 被引量:7
12
作者 wang he ZHU Jianhua +1 位作者 YANG Jingsong SHI Chaoying 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第3期59-66,共8页
Many synthetic aperture radar (SAR) wave height retrieval algorithms have been developed.However,the wave height retrievals from most existing methods either depend on other input as the first guess or are restricted ... Many synthetic aperture radar (SAR) wave height retrieval algorithms have been developed.However,the wave height retrievals from most existing methods either depend on other input as the first guess or are restricted to the long wave regime.A semiempirical algorithm is presented,which has the objective to estimate the wave height from SAR imagery without any prior knowledge.The proposed novel algorithm was developed based on the theoretical SAR ocean wave imaging mechanism and the empirical relation between two types of wave period.The dependency of the proposed model on radar incident and wave direction was analyzed.For Envisat advanced synthetic aperture radar (ASAR) wave mode data,the model can be reduced to the simple form with two input parameters,i.e.,the cutoff wavelength and peak wavelength of ocean wave,which can be retrieved from SAR imagery without any prior knowledge of wind or wave.Using Envisat ASAR wave mode data and the collocated buoy measurements from NDBC,the scmicmpirical algorithm is validated and compared with the Envisat ASAR level 2 products.The root-mean-square-error (RMSE) and scatter index (SI) in respect to the in situ measurements are 0.52 m and 19% respectively.Validation results indicate that,for Envisat ASAR wave mode data,the proposed method works well. 展开更多
关键词 significant wave height SAR RETRIEVAL VALIDATION
下载PDF
Nematode Diversity in Phaeozem Agroecosystems of Northeast China 被引量:5
13
作者 LI Qi JIANG Yong +2 位作者 LIANG Wen-Ju wang he JIANG Si-Wei 《Pedosphere》 SCIE CAS CSCD 2009年第5期597-605,共9页
The diversity and distribution patterns of soil nematode communities in phaeozem agroecosystems of Northeast China were assessed to evaluate nematode taxonomic diversity and functional diversity in relation to climati... The diversity and distribution patterns of soil nematode communities in phaeozem agroecosystems of Northeast China were assessed to evaluate nematode taxonomic diversity and functional diversity in relation to climatic condition and soil characteristics in human modified landscape. Along the latitudinal gradient, soil samples were collected from north (Hailun) to south (Gongzhuling) down to a depth of 100 cm with intervals of 030, 20-40, 40-60, 60-80, and 80-100 cm. The nematode abundance and taxonomic diversity (generic richness) were lower at Hailun than at other sites, and higher values of evenness were observed at Hailun and Harbin than at Dehui and Gongzhuling. Nematode faunal analysis revealed that soil food web at Hailun was sueeessionally more mature or structured, and the environment little disturbed, while at Harbin and Gongzhuling, the soil food web was degraded with stressed environment. The environmental variables relevant in explaining the patterns of nematode distribution and diversity in phaeozem agroecosystems, using canonical correspondence analysis (CCA), were the mean annual temperature, total nitrogen, electrical conductivity, mean annual precipitation, and other soil properties. Among these variables, the mean annual temperature was a relatively important factor, which could explain 29.05% of the variations in nematode composition. 展开更多
关键词 agricultural disturbance canonical correspondence analysis maize field nematode faunal analysis soil biodiversity
下载PDF
中国能源政策2023年回顾与2024年调整研判 被引量:3
14
作者 郭海涛 徐东 +1 位作者 王贺 刘艺迪 《国际石油经济》 2024年第2期14-21,共8页
2023年,在世界地缘政治动荡、能源价格中高位徘徊、应对气候变化以及绿色低碳转型等多种因素持续交错叠加背景下,中国能源政策坚持战略定力,进一步聚焦能源安全保障、促进多品种能源融合发展、能源与数字信息化技术耦合协同、推动天然... 2023年,在世界地缘政治动荡、能源价格中高位徘徊、应对气候变化以及绿色低碳转型等多种因素持续交错叠加背景下,中国能源政策坚持战略定力,进一步聚焦能源安全保障、促进多品种能源融合发展、能源与数字信息化技术耦合协同、推动天然气加快发展,以及进一步加快绿色低碳能源布局和规模发展。2024年,中国将继续深化能源体制改革,提升能源产业链供应链韧性和安全水平;提升天然气在能源结构中的地位,促进天然气全产业链发展;推动新型能源体系建设,促进电力市场与新能源发展;加快碳市场体系建设,遏制碳排放上升态势,最终为构建新型能源体系和促进能源产业现代化发展夯实政策基础。 展开更多
关键词 能源政策 能源安全 体制改革 新型能源体系 碳市场
下载PDF
Assessment of the initial sea surface temperature product of the scanning microwave radiometer aboard on HY-2 satellite 被引量:5
15
作者 ZHAO Yili ZHU Jianhua +5 位作者 LIN Mingsen CheN Chuntao HUANG Xiaoqi wang he ZHANG Youguang PENG Hailong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第1期109-113,共5页
HY-2 satellite is the first satellite for dynamic environmental parameters measurement of China,which was launched on 16th August 2011.A scanning microwave radiometer(RM) is carried for sea surface temperature(SST... HY-2 satellite is the first satellite for dynamic environmental parameters measurement of China,which was launched on 16th August 2011.A scanning microwave radiometer(RM) is carried for sea surface temperature(SST),sea surface wind speed,columnar water vapor and columnar cloud liquid water detection.In this paper,the initial SST product of RM was validated with in-situ data of National Data of Buoy Center(NDBC) mooring and Argo buoy.The validation results indicate the accuracy of RM SST is better than 1.7 C.The comparison of RM SST and WindSat SST shows the former is warmer than the latter at high sea surface wind speed and the difference between these SSTs is depend on the sea surface wind speed.Then,the relationship between the errors of RM SST and sea surface wind speed was analyzed using NDBC mooring measurements.Based on the results of assessment and errors analysis,the suggestions of taking account of the affection of sea surface wind speed and using sea surface wind speed and direction derived from the microwave scatteromter aboard on HY-2 for SST product calibration were given for retrieval algorithm improvement. 展开更多
关键词 validation sea surface temperature HY-2 satellite microwave radiometer
下载PDF
极早产儿生后1个月肠道菌群的动态变化及分布特征 被引量:1
16
作者 许景林 李华梅 +2 位作者 傅春燕 王赫 陈冬梅 《临床儿科杂志》 CAS CSCD 北大核心 2024年第4期311-317,共7页
目的了解极早产儿生后1个月肠道菌群的动态变化及分布特征,为益生菌早期干预提供理论依据。方法采取前瞻性研究方法,选取2022年9月至2023年3月本院收治的极早产儿为研究对象,收集生后第7、14、21、28天的粪便标本行16 S rRNA高通量测序... 目的了解极早产儿生后1个月肠道菌群的动态变化及分布特征,为益生菌早期干预提供理论依据。方法采取前瞻性研究方法,选取2022年9月至2023年3月本院收治的极早产儿为研究对象,收集生后第7、14、21、28天的粪便标本行16 S rRNA高通量测序及生物信息分析。结果共纳入极早产儿35例,男22例,女13例,出生胎龄210±11天,出生体重1419±339 g,收集粪便样本140份。在门水平上检测到的优势菌群包括厚壁菌门、变形菌门,占80%以上;属水平上检测到的优势菌群主要以条件致病菌为主,包括埃希菌属、梭菌属、葡萄球菌属、不动杆菌属和克雷伯杆菌属,而双歧杆菌属相对丰度均<5%。关键菌群差异分析发现,门及属水平的差异菌群主要为拟杆菌门(P=0.029)、蓝藻菌门(P=0.011)及葡萄球菌属(P=0.010)、罗氏菌属(P=0.040)。肠道菌群的多样性分析发现,四个时间点Alpla多样性指数Ace值及Shannon值比较差异无统计学差异(P>0.05),而Chao值呈逐渐下降趋势(P=0.001);四个时间点的Beta多样性分析Weighted-unifrac值分别为0.412(0.281~0.493)、0.498(0.214~0.526)、0.428(0.289~0.490)、0.143(0.077~0.423),差异有统计学意义(P<0.001)。结论极早产儿生后7~28天肠道优势菌群从厚壁菌门逐渐转变为变形菌门,并以条件致病菌为主,而双歧杆菌属定植数量少,肠道菌群多样性呈下降趋势。 展开更多
关键词 益生菌 极早产儿 肠道菌群 16S rRNA 高通量测序
下载PDF
A preliminary assessment of the sea surface wind speed production of HY-2 scanning microwave radiometer 被引量:4
17
作者 HUANG Xiaoqi ZHU Jianhua +5 位作者 LIN Mingsen ZHAO Yili wang he CheN Chuntao PENG Hailong ZHANG Youguang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第1期114-119,共6页
A scanning microwave radiometer(RM) was launched on August 16,2011,on board HY-2 satellite.The six-month long global sea surface wind speeds observed by the HY-2 scanning microwave radiometer are preliminarily valid... A scanning microwave radiometer(RM) was launched on August 16,2011,on board HY-2 satellite.The six-month long global sea surface wind speeds observed by the HY-2 scanning microwave radiometer are preliminarily validated using in-situ measurements and WindSat observations,respectively,from January to June 2012.The wind speed root-mean-square(RMS) difference of the comparisons with in-situ data is 1.89 m/s for the measurements of NDBC and 1.72 m/s for the recent four-month data measured by PY30-1 oil platform,respectively.On a global scale,the wind speeds of HY-2 RM are compared with the sea surface wind speeds derived from WindSat,the RMS difference of 1.85 m/s for HY-2 RM collocated observations data set is calculated in the same period as above.With analyzing the global map of a mean difference between HY-2 RM and WindSat,it appears that the bias of the sea surface wind speed is obviously higher in the inshore regions.In the open sea,there is a relatively higher positive bias in the mid-latitude regions due to the overestimation of wind speed observations,while the wind speeds are underestimated in the Southern Ocean by HY-2 RM relative to WindSat observations. 展开更多
关键词 HY-2 satellite scanning microwave radiometer sea surface wind speed spatial and temporal collocation validation
下载PDF
ZnO/TiO_(2)核-壳纳米结构的低温制备及其光电性能研究 被引量:1
18
作者 李丽华 王贺 +1 位作者 王航 黄金亮 《功能材料》 CAS CSCD 北大核心 2024年第1期1217-1222,共6页
ZnO因其自身的高电荷复合、化学性质活泼,导致其应用受到限制,通过表面修饰进行复合可实现电子-空穴的分离并提高其化学稳定性。以二水合醋酸锌、六水合硝酸锌、六氟钛酸铵为原料,采用溶胶-凝胶、水热和液相沉积相结合的方法,在低温条... ZnO因其自身的高电荷复合、化学性质活泼,导致其应用受到限制,通过表面修饰进行复合可实现电子-空穴的分离并提高其化学稳定性。以二水合醋酸锌、六水合硝酸锌、六氟钛酸铵为原料,采用溶胶-凝胶、水热和液相沉积相结合的方法,在低温条件下制备出ZnO/TiO_(2)单异质结。采用XRD、SEM、EDS、TEM、PL等对样品进行表征并对其光电性能进行测试。结果表明,在沉积时间为20 min时,ZnO/TiO_(2)核-壳结构形貌最规整,其中ZnO直径约115 nm,TiO_(2)薄膜厚度约7.6 nm;TiO_(2)的负载,降低了电极中光生电荷的复合,提高了ZnO对光子的收集能力,光电流密度提升大约10倍,达到0.21μA/cm^(2),表现出优异的光电化学性能。 展开更多
关键词 ZnO/TiO_(2) 核-壳结构 异质结 光电极材料 液相沉积
下载PDF
面向高比例分布式能源接入的输配网两阶段风险调度研究 被引量:1
19
作者 王鹤 刘子悦 +1 位作者 边竞 潘禹含 《电网与清洁能源》 CSCD 北大核心 2024年第1期119-129,共11页
随着大量高比例可再生能源接入配电网,潮流呈现双向化,输电网和配电网互联性增加,分散独立的调度影响电网可靠稳定运行水平。面对输网与配网间互济需求增强的现状,提出了面向高比例分布式能源接入的输配电网两阶段风险调度研究。首先以... 随着大量高比例可再生能源接入配电网,潮流呈现双向化,输电网和配电网互联性增加,分散独立的调度影响电网可靠稳定运行水平。面对输网与配网间互济需求增强的现状,提出了面向高比例分布式能源接入的输配电网两阶段风险调度研究。首先以最小运行成本为目标,构建考虑输配电网不同运行风险的日前经济调度模型,在风险限值约束情况下协同优化系统源网荷储多种可调资源;其次构建目标函数为综合风险值最小的日内风险调度模型,计算三类运行风险指标值,对日前可调控资源进行出力计划调整;最后通过改进的粒子群算例求解模型,证明了该模型可使输配电网间交互协调,协同优化运行成本与运行风险,验证了所提两阶段风险调度模型的有效性和优越性。 展开更多
关键词 分布式新能源 输配电网 源网荷储 风险调度
下载PDF
Bioaccumulation of heavy metals by Phragmites australis cultivated in synthesized substrates 被引量:2
20
作者 wang he JIA Yongfeng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第10期1409-1414,共6页
Accumulation of heavy metals from various oxides with adsorbed cadmium by wetland plant Phragmites australis was studied to evaluate the fate of heavy metals in the sediment of constructed wetlands. Hoagland solution ... Accumulation of heavy metals from various oxides with adsorbed cadmium by wetland plant Phragmites australis was studied to evaluate the fate of heavy metals in the sediment of constructed wetlands. Hoagland solution was used as nutrition supply, and single metal oxide with adsorbed cadmium was applied as contaminant to study the accumulation characteristics of cadmium and the substrate metals by P. australis. After 45-d treatment, the bioaccumulation degree in root followed the order: Al(OH)3 〉 Al2O3 〉 Fe3O4 〉 MnO2 〉 FeOOH. Heavy metals absorbed by P. australis were largely immobilized by the roots with little translocation to aboveground parts. 展开更多
关键词 heavy metals BIOACCUMULATION metal oxides ADSORPTION
下载PDF
上一页 1 2 79 下一页 到第
使用帮助 返回顶部