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海洋油气工程专业英语“JITT”互动式教学模式的构建与实施 被引量:3
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作者 李吉 杨二龙 +1 位作者 张海翔 李虹达 《高教学刊》 2020年第32期81-84,共4页
“海洋油气工程专业英语”JITT互动式教学模式的构建是以“一带一路”油气战略人才需求为导向,为解决传统专业英语教学的不足,借助“线上教学平台”,设计一套满足国际化创新人才能力需求的培养模式及课程体系及实施方案,并将其贯穿整个... “海洋油气工程专业英语”JITT互动式教学模式的构建是以“一带一路”油气战略人才需求为导向,为解决传统专业英语教学的不足,借助“线上教学平台”,设计一套满足国际化创新人才能力需求的培养模式及课程体系及实施方案,并将其贯穿整个教学周期,在实践中不断完善;建立对接石油企业的课程体系优化机制,以保证教学质量以循环迭代模式持续改进。 展开更多
关键词 海洋油气 专业英语 互动式教学
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过表达钙调素类似蛋白基因CML25-like诱导黄瓜单性结实的研究 被引量:6
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作者 刘嘉斐 张璐 +4 位作者 孟永娇 段莉莉 罗雨薇 李季 陈劲枫 《南京农业大学学报》 CAS CSCD 北大核心 2019年第3期421-429,共9页
[目的]钙调素类似蛋白(calmodulin-like protein,CML)是一类含有EF-hand结构域的钙受体蛋白,与植物细胞的分裂及形态建成密切相关。本文基于前期克隆的一个黄瓜果实特异性表达基因CML25-like,研究其调控单性结实的机制。[方法]采用RT-q... [目的]钙调素类似蛋白(calmodulin-like protein,CML)是一类含有EF-hand结构域的钙受体蛋白,与植物细胞的分裂及形态建成密切相关。本文基于前期克隆的一个黄瓜果实特异性表达基因CML25-like,研究其调控单性结实的机制。[方法]采用RT-qPCR方法研究CML25-like表达的时空特点;构建植物表达载体pLP100-35S-CML25-like,利用农杆菌介导子叶节法转化黄瓜自交系CCMC,并研究转基因植株的表达特点;观察转基因植株的表型,采用RT-qPCR方法检测其坐果期激素相关基因的表达变化。[结果]CML25-like在黄瓜幼叶和雌花中表达量最高,在雄花中表达量最低,而且CML25-like在果实发育过程中上调表达,在果实败育过程中下调表达;性状统计发现过表达CML25-like植株的单性结实率最高可达到98.25%,比对照CCMC提高了86%,而且单性结实果实与对照授粉果实的长度和横径均无明显差异。RT-qPCR检测结果显示,在转基因植株坐果期22个激素相关基因中有16个显著上调表达。[结论]CML25-like基因的活跃表达与果实发育密切相关,而且CML25-like能够诱导黄瓜单性结实,促进果实膨大,推测CML25-like通过上调弱单性结实黄瓜子房中激素相关基因表达而诱导单性结实。 展开更多
关键词 黄瓜 钙调素类似蛋白 单性结实 激素相关基因
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基于BAFF介导的NF-κB非经典信号通路探讨梅花生津饮对干燥综合征模型小鼠的治疗机制
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作者 李奇玮 王燕 李冀 《江苏中医药》 CAS 2025年第1期67-73,共7页
目的:基于B细胞活化因子(BAFF)介导的核因子(NF)-κB非经典信号通路探讨梅花生津饮对干燥综合征(SS)模型小鼠的作用机制。方法:选择杂交型小鼠中的非肥胖性糖尿病型(NOD)/Ltj小鼠作为SS疾病模型动物,同时应用与之遗传背景相似的C57BL/6... 目的:基于B细胞活化因子(BAFF)介导的核因子(NF)-κB非经典信号通路探讨梅花生津饮对干燥综合征(SS)模型小鼠的作用机制。方法:选择杂交型小鼠中的非肥胖性糖尿病型(NOD)/Ltj小鼠作为SS疾病模型动物,同时应用与之遗传背景相似的C57BL/6小鼠作为健康模型动物。将NOD小鼠随机分为模型组、硫酸羟氯喹组(每日给药量0.07 g/kg)和梅花生津饮低剂量(每日给药量11.11 g/kg)组、中剂量(每日给药量22.23 g/kg)组、高剂量(每日给药量44.46 g/kg)组,每组6只,另取6只C57BL/6小鼠为正常组。各组每日灌胃给予相应药物,模型组与空白组每日灌胃给予等量蒸馏水,均每日1次,连续6周。采用蛋白质免疫印迹法(Western blot法)检测各组小鼠颌下腺组织BAFF、B淋巴细胞刺激因子受体(BAFFR)、IκB激酶-α(IKKα)、NF-κB2(p52)、B淋巴细胞瘤-2基因(Bcl-2)蛋白的表达;采用实时荧光定量逆转录聚合酶链反应(RT-PCR)检测各组小鼠颌下腺组织BAFF、IKKα、p52 mRNA表达水平;采用酶联免疫吸附法(ELISA法)检测各组小鼠血清趋化因子CXC配体13(CXCL13)表达水平;采用流式细胞术检测各组小鼠血清B细胞亚群的表达。结果:模型组小鼠颌下腺组织BAFF、BAFFR、IKKα、p52、Bcl-2蛋白相对表达量,BAFF、IKKα、p52 mRNA表达水平均明显高于正常组(P<0.01);硫酸羟氯喹组与梅花生津饮中、高剂量组上述指标均明显低于模型组(P<0.05,P<0.01);梅花生津饮低剂量组小鼠颌下腺组织p52、Bcl-2蛋白相对表达量,IKKα、p52 mRNA表达水平明显低于模型组(P<0.01,P<0.05);梅花生津饮中、高剂量对上述指标的改善作用与硫酸羟氯喹相当或明显优于硫酸羟氯喹(P<0.05,P<0.01)。模型组小鼠血清CXCL13含量明显高于正常组(P<0.01);硫酸羟氯喹组与梅花生津饮中、高剂量组小鼠血清CXCL13含量明显均明显低于模型组(P<0.01);梅花生津饮中、高剂量对上述指标的改善作用均明显优于硫酸羟氯喹(P<0.05,P<0.01)。模型组小鼠血清CD19^(+)、CD27^(+)CD19^(+)、CD185^(+)CD19^(+)百分比均明显高于正常组(P<0.01);硫酸羟氯喹组与梅花生津饮中、高剂量组上述指标均明显低于模型组(P<0.05,P<0.01),梅花生津饮低剂量组小鼠血清CD19^(+)、CD27^(+)CD19^(+)百分比均明显低于模型组(P<0.05);梅花生津饮中、高剂量对上述指标的改善作用与硫酸羟氯喹相当。梅花生津饮对上述各指标的改善作用均表现出一定的剂量依赖性。结论:梅花生津饮可调节CXCL13/CXCR5轴,降低对B细胞的趋化作用,影响总B细胞及记忆B细胞的比例,其可能通过BAFF介导的NF-κB非经典信号通路对干燥综合征模型小鼠发挥治疗作用。 展开更多
关键词 干燥综合征 梅花生津饮 NF-κB非经典信号通路 血清趋化因子CXC配体13 B细胞亚群
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纳米SiO_(2)复合粒子/有机硅低聚物透明超疏水复合涂层的制备及其性能 被引量:1
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作者 李冀 郭浩彬 +2 位作者 叶向东 郗长青 王权岱 《精细化工》 EI CAS CSCD 北大核心 2024年第3期572-579,共8页
将Stöber法制备的胶体SiO_(2)粒子溶液与粉体SiO_(2)粒子进行物理共混得到SiO_(2)复合粒子溶液,以三乙氧基甲基硅烷(MTES)与正硅酸乙酯(TEOS)为前驱体制备的酸性有机硅低聚物为黏结剂,使用3-氨丙基三甲氧基硅(KH540)与全氟癸基三... 将Stöber法制备的胶体SiO_(2)粒子溶液与粉体SiO_(2)粒子进行物理共混得到SiO_(2)复合粒子溶液,以三乙氧基甲基硅烷(MTES)与正硅酸乙酯(TEOS)为前驱体制备的酸性有机硅低聚物为黏结剂,使用3-氨丙基三甲氧基硅(KH540)与全氟癸基三甲基氧硅(PFDT)对其进行改性,通过喷涂法在玻璃基底上制备出SiO_(2)复合粒子/酸性有机硅低聚物复合透明超疏水涂层。考察了SiO_(2)复合粒子、酸性有机硅低聚物、KH540及PFDT对复合涂层的影响。结果表明,当SiO_(2)复合粒子溶液由粒径为110 nm的胶体SiO_(2)粒子溶液与粒径为50 nm的粉体SiO_(2)粒子(其用量为胶体SiO_(2)粒子溶液质量的1%)组成、SiO_(2)复合粒子溶液与酸性有机硅稀释液质量比为4∶1、KH540与PFDT的添加量(以混合液总质量计,下同)均为1%时,制备的复合涂层在可见光波长范围内透光率可达88%,静态接触角达155°,在800目砂纸上磨损60 cm后仍能保持超疏水性能,具有良好的自清洁性。 展开更多
关键词 纳米SiO_(2) 透明超疏水涂层 有机硅低聚物 制备 性能 功能材料
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“人工智能+大数据”在医院服务流程管理中的应用与实践 被引量:4
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作者 聂柔佳 李吉 李旭东 《中国医院管理》 北大核心 2024年第7期94-96,共3页
智慧医疗和数字化转型是医疗领域发展的方向。以吉林大学中日联谊医院实践为例,探讨了“人工智能+大数据”在医院精细化服务流程管理中的应用,着重分析其在提升医疗服务水平和满足患者需求方面的潜在优势。通过智慧医疗路径设计和构建... 智慧医疗和数字化转型是医疗领域发展的方向。以吉林大学中日联谊医院实践为例,探讨了“人工智能+大数据”在医院精细化服务流程管理中的应用,着重分析其在提升医疗服务水平和满足患者需求方面的潜在优势。通过智慧医疗路径设计和构建精细化智慧管理服务流程的框架,为医院数字化转型提供思路和方法。 展开更多
关键词 人工智能 大数据 精细化管理 服务流程
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Properties of Functionalized Graphene/Room Temperature Vulcanized Silicone Rubber Composites Prepared by an In-situ Reduction Method 被引量:14
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作者 马文石 li ji +2 位作者 DENG Bangjun liN Xiaodan ZHAO Xusheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第1期127-131,共5页
Functionalized graphene oxide (FGO) was prepared by treating graphene oxide with y-aminopropyl triethoxysilane (KH-550) before the mixture was dispersed into a, ω-dihydroxy polydimethylsiloxane to get room temper... Functionalized graphene oxide (FGO) was prepared by treating graphene oxide with y-aminopropyl triethoxysilane (KH-550) before the mixture was dispersed into a, ω-dihydroxy polydimethylsiloxane to get room temperature vulcanized (RTV) silicone rubber composites by solution casting. The cured composites were then reduced with hydrazine hydrate to obtain functionalized graphene (FG)/RTV silicone rubber composites. The structures of FGO and the resultant composites were characterized by atomic force microscopy, FT-IR spectra and X-ray diffraction. KH-550 was found to be grafted onto graphene sheets, leading to an increased interlayer spacing. Significant improvements in thermal and mechanical properties were obtained. Both the FGO/RTV silicone rubber composite contain 1.0 wt% of FGO, and its reduced product showed an increase of one-step weight loss temperature with 61 ℃ and 133 ℃ higher than that of pure silicone rubber. Tensile strength and elongation at break of FG/RTV silicone rubber composite (with 0.5 wt% FGO content) increased by 175% and 67%, respectively, compared with those of pure silicone rubber. 展开更多
关键词 COMPOSITES RUBBER mechanical properties
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Multilinear commutators of BMO functions and multilinear singular integrals with non-smooth kernels 被引量:8
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作者 liAN jia-li li ji WU Huo-xiong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第1期109-120,共12页
This paper is concerned with certain multilinear commutators of BMO functions and multilinear singular integral operators with non-smooth kernels. By the sharp maximal functions estimates, the weighted norm inequaliti... This paper is concerned with certain multilinear commutators of BMO functions and multilinear singular integral operators with non-smooth kernels. By the sharp maximal functions estimates, the weighted norm inequalities for this kind of commutators are established. 展开更多
关键词 Multilineav operator COMMUTATOR non-smooth kernel sharp maximal function weighted norminequality.
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Molten salt synthesis of porous carbon and its application in supercapacitors: A review 被引量:7
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作者 Zhongya Pang Guangshi li +4 位作者 Xiaolu Xiong li ji Qian Xu Xingli Zou Xionggang Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第10期622-640,I0016,共20页
Carbon materials have taken an important role in supercapacitor applications due to their outstanding features of large surface area,low price,and stable physicochemical properties.Considerable research efforts have b... Carbon materials have taken an important role in supercapacitor applications due to their outstanding features of large surface area,low price,and stable physicochemical properties.Considerable research efforts have been devoted to the development of novel synthesis strategy for the preparation of porous carbon materials in recent years.In particular,molten salt strategy represents an emerging and promising method,whereby it has shown great potential in achieving tailored production of porous carbon.It has been proved that the molten salt-assisted production of carbon via the direct carbonization of carbonaceous precursors is an effective approach.Furthermore,with the incorporation of electrochemical technology,molten salt synthesis of porous carbon has become flexible and diversiform.Here,this review focuses on the mainstream molten salt synthesis strategies for the production of porous carbon materials,which includes direct molten salt carbonization process,capture and electrochemical conversion of CO_(2)to value-added carbon,electrochemical exfoliation of graphite to graphene-based materials,and electrochemical etching of carbides to new-type carbide-derived carbon materials.The reaction mechanisms and recent advances for these strategies are reviewed and discussed systematically.The morphological and structural properties and capacitive performances of the obtained carbon materials are summarized to reveal their appealing points for supercapacitor applications.Moreover,the opportunities and challenges of the molten salt synthesis strategy for the preparation of carbon materials are also discussed in this review to provide inspiration to the future researches. 展开更多
关键词 Molten salt synthesis Porous carbon CO_(2)conversion GRAPHENE Carbide-derived carbon
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CLIMATIC FEATURES OF SUMMER TEMPERATURE IN NORTHEAST CHINA UNDER WARMING BACKGROUND 被引量:6
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作者 li ji GONG Qiang ZHAO lian-wei 《Chinese Geographical Science》 SCIE CSCD 2005年第4期337-342,共6页
By using,summer temperature data in 26 stations from 1951 to 2003, the variation characteristics of summer temperature in Northeast China (NET) were analyzed based on the background of climate wanning. The results s... By using,summer temperature data in 26 stations from 1951 to 2003, the variation characteristics of summer temperature in Northeast China (NET) were analyzed based on the background of climate wanning. The results showed that the warming in summer was 0.15~C/10a in Northeast China, which was higher than that on the global, Northern Hemisphere or Northeast Asia scale in the recent 50 years. The responses of NET to global warming were shown in 3 aspects mainly. Firstly, it became warm and the average temperature increased in summer; secondly, the temperature variability increased, which displayed the increase of climatic instability; thirdly, the disaster of low temperature decreased and high temperature damage increased obviously, but the disaster of low temperature still existed in some areas under global warming background, which would be worthy of notice further. 展开更多
关键词 Northeast China summer temperature climate features global warming disaster of low temperature
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TiO_(2)/FACs与TiO_(2)/Mullite复合材料的制备及其光催化性能
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作者 胡其国 李济 +1 位作者 马岚 李小龙 《中国陶瓷》 CAS CSCD 北大核心 2023年第1期26-31,共6页
分别以粉煤灰漂珠(简记为FACs)与海胆状莫来石球(简记为Mullite)为基体,采用溶胶浸渍工艺制备了TiO_(2)/FACs与TiO_(2)/Mullite型复合材料。通过X射线衍射(XRD)、扫描电子显微镜(SEM)以及电子能谱(EDS)对制备的材料进行了表征。研究了Ti... 分别以粉煤灰漂珠(简记为FACs)与海胆状莫来石球(简记为Mullite)为基体,采用溶胶浸渍工艺制备了TiO_(2)/FACs与TiO_(2)/Mullite型复合材料。通过X射线衍射(XRD)、扫描电子显微镜(SEM)以及电子能谱(EDS)对制备的材料进行了表征。研究了TiO_(2)/FACs与TiO_(2)/Mullite型复合材料在紫外光照射下对罗丹明B(RhB)的光催化性能。结果表明:经500℃煅烧后形成的锐钛矿型TiO_(2)均成功负载到粉煤灰漂珠与莫来石晶体上,在粉煤灰漂珠表面覆盖了一层厚薄不均的纳米级别的TiO_(2)薄膜,而在莫来石晶体上则出现了大量细小的TiO_(2)颗粒;在降解染料时间为180 min,TiO_(2)/FACs与TiO_(2)/Mullite复合材料对罗丹明B染料的降解率分别为84.8%和96.4%,降解速率为0.01088min-1和0.02885 min-1。 展开更多
关键词 粉煤灰漂珠 莫来石 TiO_(2) TiO_(2)/FACs TiO_(2)/Mullite 光催化
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Continuous electrodeposition of silicon and germanium micro/nanowires from their oxides precursors in molten salt 被引量:4
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作者 Xingli Zou li ji +2 位作者 Zhongya Pang Qian Xu Xionggang Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期147-153,共7页
In recent years,silicon(Si)and germanium(Ge)materials have been considered as promising highperformance anode materials for lithium-ion batteries due to their high theoretical capacities.It is of great importance to d... In recent years,silicon(Si)and germanium(Ge)materials have been considered as promising highperformance anode materials for lithium-ion batteries due to their high theoretical capacities.It is of great importance to design and synthesize micro/nanostructured Si and Ge materials.In this work,we demonstrated that Si,Ge and SiGe micro/nanowires can be continuously synthesized from their oxides precursors through molten salt electrodeposition.The electrochemical synthesis processes have been investigated systematically,and the deposited Si,Ge and SiGe micro/nanowires have been characterized and compared.The results show that the micro/nanostructured Si and Ge materials with tunable morphology can be facilely and continuously produced via molten salt electrodeposition.The electrodeposition process generally includes calcium oxide-assisted dissolution and electrodeposition processes,and the morphologies of the deposited Si and Ge products can be controlled by varying conditions.Si micro/nanowires,Si films,Ge micro/nanowires,and Ge particles can be continuously synthesized in a controlled manner. 展开更多
关键词 Silicon MATERIALS GERMANIUM MATERIALS MOLTEN salt ELECTRODEPOSITION ELECTROCHEMISTRY
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考虑平抑未来时刻风电波动的混合储能系统超前模糊控制策略 被引量:2
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作者 周丹 袁至 +1 位作者 李骥 范玮 《发电技术》 CSCD 2024年第3期412-422,共11页
【目的】现有的混合储能系统控制策略难以在保持荷电状态(state of charge,SOC)处于合理范围的同时,满足未来时刻风电波动造成的混合储能系统超前充放电需求,因此提出一种考虑平抑未来时刻风电功率波动的混合储能系统超前模糊控制策略... 【目的】现有的混合储能系统控制策略难以在保持荷电状态(state of charge,SOC)处于合理范围的同时,满足未来时刻风电波动造成的混合储能系统超前充放电需求,因此提出一种考虑平抑未来时刻风电功率波动的混合储能系统超前模糊控制策略。【方法】首先,通过采用集合经验模态分解(ensemble empirical mode decomposition,EEMD)方法分解得到不同类型储能设备需要平抑的风电功率;其次,根据混合储能系统SOC和功率饱和程度整定功率修正参数,对混合储能系统输出功率进行修正;再次,由风电预测算法得到前瞻周期内风电功率预测值,根据前瞻周期内风电功率波动情况和超前控制理论整定提前充放电参数,校正储能系统输出功率;最后,以某风电场的实际数据为例,通过仿真验证了所提超前模糊控制策略的有效性。【结果】提出的控制策略不仅能够降低风电并网波动越限概率,显著减少总输出功率与目标功率偏差值,而且能够使混合储能系统的SOC控制在合理范围内。【结论】该策略可以为平抑风电波动的相关研究提供有益参考。 展开更多
关键词 风力发电 混合储能系统 模糊控制 超前控制
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网络基础设施建设与企业数字化转型:理论机制与实证检验 被引量:8
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作者 王磊 李吉 《现代经济探讨》 CSSCI 北大核心 2024年第1期77-89,共13页
企业数字化转型是数字经济与实体经济深度融合在微观层面的具体体现,网络基础设施建设为其提供了有力支撑。基于2007-2021年沪深A股上市公司数据,以“宽带中国”试点政策为准自然实验,构建多时期双重差分模型实证检验网络基础设施建设... 企业数字化转型是数字经济与实体经济深度融合在微观层面的具体体现,网络基础设施建设为其提供了有力支撑。基于2007-2021年沪深A股上市公司数据,以“宽带中国”试点政策为准自然实验,构建多时期双重差分模型实证检验网络基础设施建设对企业数字化转型的影响及作用机制。研究表明,网络基础设施建设显著推动了企业数字化转型,并通过创新激励和信贷融资渠道实现;CEO信息技术背景和CEO风险偏好均强化了网络基础设施建设对企业数字化转型的促进作用;网络基础设施建设对企业数字化转型提升效果在具有不同产权性质、技术禀赋、生命周期阶段以及经济政策环境中的企业具有异质性。 展开更多
关键词 网络基础设施 “宽带中国” 数字化转型 双重差分模型
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中深层地埋管热泵供热系统运行特性实测研究 被引量:2
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作者 邓杰文 彭晨玮 +5 位作者 朱超 李骥 孔维政 李建峰 强文博 魏庆芃 《暖通空调》 2024年第4期113-119,共7页
通过大量工程实测研究,总结了中深层地埋管热泵供热技术的运行特性。中深层地埋管具有出水温度高、取热功率大、长期运行稳定的特点,为热泵系统提供了高品位的低温热源,以提升其运行性能;同时中深层地埋管自身存在间歇蓄热特性,能很好... 通过大量工程实测研究,总结了中深层地埋管热泵供热技术的运行特性。中深层地埋管具有出水温度高、取热功率大、长期运行稳定的特点,为热泵系统提供了高品位的低温热源,以提升其运行性能;同时中深层地埋管自身存在间歇蓄热特性,能很好地满足建筑供热需求变化与柔性用能;无级变频热泵机组更适合与中深层地埋管匹配运行,节能减排效果显著;热源侧水系统具有小流量、大扬程,且阻力随着流量变化而大幅度变化的特性。研究结果可为提升该技术的供热性能提供关键指导。 展开更多
关键词 中深层地埋管 热泵系统 热源侧水系统 运行特征 阻力特性 实测研究
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煅烧温度对TiO_(2)/FACs与TiO_(2)/Mullite复合材料物相结构及其光催化性能的影响
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作者 胡其国 李鑫浩 +1 位作者 李济 李小龙 《中国陶瓷》 CAS CSCD 北大核心 2023年第7期35-40,共6页
采用溶胶浸渍工艺于不同煅烧温度下(300~700℃)制备了二氧化钛/粉煤灰漂珠(简称Ti O_(2)/FACs)与二氧化钛/莫来石(简称Ti O_(2)/Mullite)复合材料,采用X射线衍射仪(XRD)、场发射扫描电子显微镜(SEM)、红外吸收光谱、紫外-可见分光光度... 采用溶胶浸渍工艺于不同煅烧温度下(300~700℃)制备了二氧化钛/粉煤灰漂珠(简称Ti O_(2)/FACs)与二氧化钛/莫来石(简称Ti O_(2)/Mullite)复合材料,采用X射线衍射仪(XRD)、场发射扫描电子显微镜(SEM)、红外吸收光谱、紫外-可见分光光度计表征了材料的物相结构和光催化性能,研究了煅烧温度对Ti O_(2)/FACs与Ti O_(2)/Mullite复合材料物相结构和光催化性能的影响。结果表明:煅烧温度的高低对Ti O_(2)的形成产生重要影响,在400~600℃可获得单一的锐钛矿晶型,温度过高会产生金红石相,过低则不利于Ti O_(2)的形成;Ti O_(2)/FACs与Ti O_(2)/Mullite复合材料对罗丹明B染料的光催化降解效率随着煅烧温度的升高先上升后降低,经500℃煅烧制备的复合材料光催化性能最佳,锐钛矿型Ti O_(2)分别以纳米级的Ti O_(2)薄膜以及纳米级的颗粒负载于粉煤灰漂珠与莫来石晶体上;Ti O_(2)在粉煤灰漂珠与莫来石晶体上均属于物理吸附,并未形成相应的化学键。 展开更多
关键词 煅烧温度 莫来石 粉煤灰漂珠 物相结构 光催化性能
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A Lightweight Model of VGG-U-Net for Remote Sensing Image Classification 被引量:2
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作者 Mu Ye li ji +9 位作者 Luo Tianye li Sihan Zhang Tong Feng Ruilong Hu Tianli Gong He Guo Ying Sun Yu Thobela Louis Tyasi li Shijun 《Computers, Materials & Continua》 SCIE EI 2022年第12期6195-6205,共11页
Remote sensing image analysis is a basic and practical research hotspot in remote sensing science.Remote sensing images contain abundant ground object information and it can be used in urban planning,agricultural moni... Remote sensing image analysis is a basic and practical research hotspot in remote sensing science.Remote sensing images contain abundant ground object information and it can be used in urban planning,agricultural monitoring,ecological services,geological exploration and other aspects.In this paper,we propose a lightweight model combining vgg-16 and u-net network.By combining two convolutional neural networks,we classify scenes of remote sensing images.While ensuring the accuracy of the model,try to reduce the memory of themodel.According to the experimental results of this paper,we have improved the accuracy of the model to 98%.The memory size of the model is 3.4 MB.At the same time,The classification and convergence speed of the model are greatly improved.We simultaneously take the remote sensing scene image of 64×64 as input into the designed model.As the accuracy of the model is 97%,it is proved that the model designed in this paper is also suitable for remote sensing images with few target feature points and low accuracy.Therefore,the model has a good application prospect in the classification of remote sensing images with few target feature points and low pixels. 展开更多
关键词 VGG-16 U-Net fewer feature points nonlinear correction layer zero padding
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融合改进A^(*)算法与动态窗口法的移动机器人路径规划 被引量:2
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作者 邵磊 张飞 +2 位作者 刘宏利 李季 孙文涛 《天津理工大学学报》 2024年第1期71-76,共6页
为解决移动机器人在随机障碍物环境的导航过程中,使用A星(简称A^(*))算法出现碰撞导致路径规划失败的问题,设计了一种融合改进A_(*)算法和动态窗口法(dynamic window approach,DWA)的全局动态路径规划方法。首先,从以下两方面改进传统A^... 为解决移动机器人在随机障碍物环境的导航过程中,使用A星(简称A^(*))算法出现碰撞导致路径规划失败的问题,设计了一种融合改进A_(*)算法和动态窗口法(dynamic window approach,DWA)的全局动态路径规划方法。首先,从以下两方面改进传统A^(*)算法:混合使用4邻域和8邻域A^(*)搜索算法,与通过删除冗余路径点和转折点来提高路径的平滑性;接着将改进A^(*)算法与DWA融合,利用融合算法使移动机器人进行全局实时动态路径规划。Matlab仿真试验结果表明,改进后的A^(*)算法较传统A^(*)算法不会使机器人穿越障碍物及其顶点,这有效减少了碰撞,从而提高了安全性;融合DWA后,在获得全局最优路径的基础上,能避开静态随机障碍物和动态障碍物,这证明了融合算法有良好的路径规划能力。 展开更多
关键词 移动机器人 改进A^(*)算法 动态窗口法(DWA) 路径规划 算法融合
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Modification of total and phosphorus mineralizing bacterial communities associated with Zea mays L.through plant development and fertilization regimes 被引量:1
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作者 XIN Yuan-yuan Anisur RAHMAN +3 位作者 li Hui-xiu XU Ting DING Guo-chun li ji 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第11期3026-3038,共13页
Harnessing the rhizospheric microbiome,including phosphorus mineralizing bacteria(PMB),is a promising technique for maintaining sustainability and productivity in intensive agricultural systems.However,it is unclear a... Harnessing the rhizospheric microbiome,including phosphorus mineralizing bacteria(PMB),is a promising technique for maintaining sustainability and productivity in intensive agricultural systems.However,it is unclear as to which beneficial taxonomic group populations in the rhizosphere are potentially associated with the changes in soil microbiomes shifted by fertilization regimes.Herein,we analyzed the diversity and community structure of total bacteria and PMB in the rhizosphere of maize(Zea mays L.)grown in soils under 25 years of four fertilization regimes(compost,biocompost,chemical,or nonfertilized)via selective culture and Illumina sequencing of the 16S rRNA genes.Plant development explained more variations(29 and 13%,respectively)in the composition of total bacteria and PMB in the rhizosphere of maize than the different fertilization regimes.Among those genera enriched in the rhizosphere of maize,the relative abundances of Oceanobacillus,Bacillus,Achromobacter,Ensifer,Paracoccus,Ramlibacter,and Luteimonas were positively correlated with those in the bulk soil.The relative abundance of Paracoccus was significantly higher in soils fertilized by compost or biocompost than the other soils.Similar results were also observed for PMB affiliated with Ensifer,Bacillus,and Streptomyces.Although plant development was the major factor in shaping the rhizospheric microbiome of maize,fertilization regimes might have modified beneficial rhizospheric microbial taxa such as Bacillus and Ensifer. 展开更多
关键词 organic fertilization bacterial diversity phosphorus mineralizing bacteria(PMB) Zea mays L. RHIZOSPHERE
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高容量正极材料LiNi_(0.6)Co_(0.2)Mn_(0.2)O_2的制备及性能研究 被引量:1
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作者 孙勇疆 符泽卫 +2 位作者 李季 刘良彬 肖建伟 《电子元件与材料》 CAS CSCD 北大核心 2018年第9期21-27,32,共8页
采用控制结晶法,预先合成出致密的球形前驱体Ni_(0.6)Co_(0.2)M n_(0.2)(OH)_2。前驱体与Li_2CO_3混合均匀后于高温条件下烧结,再进行复烧即可制备出表面光滑致密、振实密度高、容量高的正极材料Li Ni_(0.6)Co_(0.2)M n_(0.2)O_2。利用... 采用控制结晶法,预先合成出致密的球形前驱体Ni_(0.6)Co_(0.2)M n_(0.2)(OH)_2。前驱体与Li_2CO_3混合均匀后于高温条件下烧结,再进行复烧即可制备出表面光滑致密、振实密度高、容量高的正极材料Li Ni_(0.6)Co_(0.2)M n_(0.2)O_2。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、X射线光电子能谱仪(XPS)及充电-放电测试对材料的结构和电学性能进行表征分析。研究了不同烧结及复烧温度对材料性能的影响,并分析了其影响机理。结果表明,通过优化烧结及复烧温度可以有效提高Li Ni_(0.6)Co_(0.2)M n_(0.2)O_2正极材料的电学性能。正极材料的中位粒径约为13μm,振实密度≥2.3 g/cm^3,比表面积为0.31 m^2/g,在3.0~4.3 V电位区间内,首次放电克比容量为178.51 m Ah/g,首次库伦效率为89.90%。 展开更多
关键词 正极材料 LiNi0.6Co0.2Mn0.2O2 复烧 温度 高容量 控制结晶法
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Effect of combining music media therapy with lower extremity exercise on elderly patients with diabetes mellitus 被引量:1
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作者 li ji jiao-jiao Bai +2 位作者 jiao Sun Yue Ming li-Rong Chen 《International Journal of Nursing Sciences》 2015年第3期243-247,共5页
Objective:To evaluate the compliance with lower extremity exercise and blood circulation in the feet of elderly diabetics following a combination of music media therapy and a lower extremity exercise regimen.Method:Th... Objective:To evaluate the compliance with lower extremity exercise and blood circulation in the feet of elderly diabetics following a combination of music media therapy and a lower extremity exercise regimen.Method:The 72 elderly diabetic patient subjects were divided into two groups:control group(n=38)and intervention group(n=34).Both groups were exposed to the same comprehensive therapy to control glucose levels.While the control group was given the lower extremity exercise,the intervention group received the extremity exercise in addition to the music media.Result:After three months of intervention,the adherence to the lower extremity exercise regimen in the intervention group was significantly higher than that of the control group(p<0.05).Additionally,following six months of treatment,both the dorsal artery peak values and ankle-brachial indices(ABIs)showed significant differences between the control and intervention groups(p<0.05).Conclusion:Music media treatment combined with lower extremity exercise can both significantly increase the extent of exercise compliance of elderly patients suffering from diabetes mellitus,as well as improve blood circulation in their feet. 展开更多
关键词 Diabetes mellitus Elderly Lower extremity exercise NURSING Music media
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