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深部强矿压工作面水力压裂裂纹扩展规律研究
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作者 陈立伟 王东杰 边乐 《河南理工大学学报(自然科学版)》 CAS 北大核心 2025年第1期18-28,共11页
目的为了研究深部强矿压工作面水力压裂裂纹扩展规律,方法以余吾煤矿的3号煤层S5207回风巷为工程背景,首先建立水力压裂力学模型,分析最大周向拉应变准则和裂纹扩展准则,其次通过三维数值模拟,分析水力压裂裂纹扩展影响因子D和地应力对... 目的为了研究深部强矿压工作面水力压裂裂纹扩展规律,方法以余吾煤矿的3号煤层S5207回风巷为工程背景,首先建立水力压裂力学模型,分析最大周向拉应变准则和裂纹扩展准则,其次通过三维数值模拟,分析水力压裂裂纹扩展影响因子D和地应力对水力压裂裂纹扩展规律的影响,并根据现场情况设计水力压裂试验方案,实施水力压裂增透技术,分析现场施工效果。结果结果表明:预制裂纹沿着与原裂纹呈一定角度开裂并向外延伸,其扩展方向最终与最小主应力方向垂直;随着D增大,裂纹与原裂纹的夹角越来越小,当D较大时,裂纹呈现自相似的扩展状态;不同应力场下,裂纹扩展轨迹主要取决于主应力方向,最终与最小主应力方向垂直,水力裂缝为垂直缝,且在裂纹尖端有应力集中现象;现场监测发现,裂纹扩展符合最大周向拉应变准则,裂纹尖端沿着环向拉应变最大的地方扩展,环向拉应变达到最大时裂纹开始扩展,压裂过程中出现了较大环向裂隙,裂纹沿垂直于最小主应力方向延伸,与S5207回风巷的最大水平主应力方向大致相同,与数值模拟结果接近。结论研究结果可为深部强矿压工作面水力压裂提供参考和依据。 展开更多
关键词 水力压裂 裂纹扩展 强矿压 深部岩体 数值模拟 回风巷
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北秦岭南召盆地太山庙组下部凝灰岩锆石U-Pb年龄及其地质意义
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作者 刘超 梁天 +5 位作者 杨文涛 陈浩 刘萧萧 安海花 李昕 马强分 《河南理工大学学报(自然科学版)》 CAS 北大核心 2025年第1期68-79,共12页
晚三叠世卡尼期全球古气候发生明显转变,全球降水量增加,海水温度上升了6~8℃,大量陆源碎屑物质输入海洋,导致海洋中出现碳酸盐生产危机。北秦岭南召盆地太山庙组可能记录了卡尼期洪水事件。目的为精确限定太山庙组沉积时代,凸显其地质... 晚三叠世卡尼期全球古气候发生明显转变,全球降水量增加,海水温度上升了6~8℃,大量陆源碎屑物质输入海洋,导致海洋中出现碳酸盐生产危机。北秦岭南召盆地太山庙组可能记录了卡尼期洪水事件。目的为精确限定太山庙组沉积时代,凸显其地质意义,方法采用激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)对太山庙组下部凝灰岩进行锆石U-Pb同位素定年分析。结果结果表明:凝灰岩锆石颗粒呈粒状、短柱状,无磨圆;阴极发光图像显示振荡环带结构明显;根据阴极发光图像和Th/U,认为太山庙组下部凝灰岩中18颗锆石均为火山来源,剔除轻稀土富集的锆石后,选择其中15颗锆石进行计算,得到其加权平均年龄为(241.4±1.3)Ma(1σ;MSWD=0.27),代表凝灰岩中锆石的结晶年龄;结合前人研究成果,计算出太山庙组下部平均沉积速率为20.6 m/Ma,太山庙组底界年龄约246 Ma,因此,太山庙组至少自中三叠世安尼期就开始沉积,至晚三叠世卡尼期末结束;根据南召盆地遗迹化石组合演化规律和植物孢粉变化,认为太山庙组沉积时期古气候发生了明显转变,由干旱炎热气候转变为温暖、湿润气候。结论研究结果对北秦岭南召盆地三叠纪地层划分产生了新认识,有助于研究探讨南召盆地对卡尼期洪水事件的沉积响应。 展开更多
关键词 卡尼期洪水幕 U-PB同位素定年 三叠纪 南召盆地 太山庙组 陆相沉积 火山凝灰岩
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压水堆国产SA-508-Ⅲ-1钢环境影响疲劳试验研究和预测模型开发
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作者 沈睿 刘畅 +1 位作者 唐力晨 王秉熙 《原子能科学技术》 北大核心 2025年第1期151-159,共9页
对压水堆核电厂一回路设备用国产SA-508 Gr.3 Cl.1低合金钢(简称SA-508-Ⅲ-1钢)进行室温和320℃空气环境,以及模拟压水堆一回路水环境下的疲劳性能试验研究,获得国产SA-508-Ⅲ-1钢在空气环境下的疲劳寿命最佳拟合曲线(平均曲线)。在此... 对压水堆核电厂一回路设备用国产SA-508 Gr.3 Cl.1低合金钢(简称SA-508-Ⅲ-1钢)进行室温和320℃空气环境,以及模拟压水堆一回路水环境下的疲劳性能试验研究,获得国产SA-508-Ⅲ-1钢在空气环境下的疲劳寿命最佳拟合曲线(平均曲线)。在此基础上,对影响国产SA-508-Ⅲ-1钢在压水堆核电厂一回路水环境下疲劳性能的应变速率、温度和溶解氧含量等参数的影响规律进行研究,获得各影响参数的影响函数方程。基于获得的各影响参数的函数方程,建立国产SA-508-Ⅲ-1钢的环境影响疲劳修正因子F_(en)预测模型。本文获得的压水堆核电厂一回路水环境下国产SA-508-Ⅲ-1钢的疲劳寿命都位于95%置信度限值(10^(±2σ))范围内,验证了本文预测模型的有效性。同时,本文获得的压水堆核电厂一回路水环境下国产SA-508-Ⅲ-1钢的疲劳寿命与美国阿贡国家实验室(ANL)模型所预测的寿命相比,也都位于95%置信度限值(10^(±2σ))范围内,说明ANL模型可用于国产SA-508-Ⅲ-1钢的疲劳寿命预测。本文获得的国产SA-508-Ⅲ-1钢的环境影响疲劳预测模型与ANL模型相比,更适用于国产SA-508-Ⅲ-1钢的寿命预测,为国内第3代核电厂一回路设备考虑压水堆一回路水环境影响的疲劳设计提供参考。 展开更多
关键词 压水堆核电厂 SA-508-Ⅲ-1钢 环境影响疲劳 F_(en) 预测模型
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西部大开发背景下职普融通教材建设:价值诉求、逻辑遵循与路径选择
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作者 朱德全 曹渡帆 《中国职业技术教育》 北大核心 2025年第1期42-48,57,共8页
西部地区高质量教育体系建设的关键在职普融通,职普融通的关键在课程,而课程的关键在教材建设。在西部大开发形成新格局的背景下,职普融通教材承载了更多的价值诉求,加快职普融通教材建设是促进西部地区产业转型升级的重要方式,是西部... 西部地区高质量教育体系建设的关键在职普融通,职普融通的关键在课程,而课程的关键在教材建设。在西部大开发形成新格局的背景下,职普融通教材承载了更多的价值诉求,加快职普融通教材建设是促进西部地区产业转型升级的重要方式,是西部地区教育改革发展的关键一环,更是西部地区人力资源开发的有效途径。西部大开发背景下职普融通教材建设作为一项综合性的教育工程,要遵循“区域适配”的社会逻辑、“多元一体”的文化逻辑,以及“知行合一”的教育逻辑,进而以教材为载体打破职普分离的壁垒,精准满足西部大开发战略对西部地区经济社会、文化政治与人才培养的需求。未来,西部地区职普融通教材建设要以“素质提升”为目标,以“理实共融”为重点,以“区域特色”为资源,为推进西部大开发形成新格局提供持久的教育活力。 展开更多
关键词 西部大开发 西部地区 职普融通 职业教育 教材
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健全人民当家作主制度体系:中国式现代化的政治基础
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作者 张贤明 张旭瀛 《探索》 北大核心 2025年第1期29-41,共13页
人民当家作主制度体系是全过程人民民主的制度支撑,发展全过程人民民主是中国式现代化的本质要求,因而健全人民当家作主制度体系成为中国式现代化的政治基础。人民当家作主制度体系是在马克思主义指导下内生演化于我国基本国情的制度体... 人民当家作主制度体系是全过程人民民主的制度支撑,发展全过程人民民主是中国式现代化的本质要求,因而健全人民当家作主制度体系成为中国式现代化的政治基础。人民当家作主制度体系是在马克思主义指导下内生演化于我国基本国情的制度体系。健全人民当家作主制度体系的首要前提是在马克思主义指导下,立足于中国社会文化传统的基本特征以及世界范围内民主实践的优秀成果,不断疏通人民当家作主制度体系中的结构性梗阻,拓展制度体系的应用范围和价值功用,回应中国式现代化道路中的新问题。健全人民当家作主制度体系是一项系统工程,要全面把握党的全面领导制度、人民代表大会制度、中国共产党领导的多党合作和政治协商制度、民族区域自治制度、基层群众自治制度等构成要素。需要统筹推进根本制度、基本制度和重要制度的协同衔接,科学构建系统性、整体性、协同性的结构关系,整体推进民主制度与社会发展相适应、政治民主与社会民主相结合的人民当家作主制度体系。在遵循全过程人民民主逻辑的前提下,健全“全链条、全方位、全覆盖”的人民当家作主制度体系,同时以问题为导向选择重点推进路径,既要面向国家发展中的重要问题,也要回应人民群众急难愁盼的问题,在“大问题”和“小问题”的共同解决中提升人民当家作主制度体系的制度效能。 展开更多
关键词 人民当家作主制度体系 中国式现代化 全过程人民民主
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热输入对高锰钢模拟焊接热影响区显微组织和低温韧性的影响
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作者 邸新杰 曲永涛 +1 位作者 利成宁 巴凌志 《天津大学学报(自然科学与工程技术版)》 北大核心 2025年第2期131-137,共7页
作为一种新型低温用材料,高锰钢具有低成本及优异的低温力学性能等优势,在液化天然气(LNG)储罐等领域具有广阔的应用前景.然而在实际焊接过程中,高锰钢焊接热影响区中距熔合线3 mm处的特定亚区(FL+3亚区)会出现低温韧性恶化的问题.针对... 作为一种新型低温用材料,高锰钢具有低成本及优异的低温力学性能等优势,在液化天然气(LNG)储罐等领域具有广阔的应用前景.然而在实际焊接过程中,高锰钢焊接热影响区中距熔合线3 mm处的特定亚区(FL+3亚区)会出现低温韧性恶化的问题.针对这一问题,采用焊接热模拟技术再现了不同热输入下的FL+3亚区,通过扫描电子显微镜、电子探针X射线显微分析仪和透射电子显微镜观察晶界比例、偏析及析出相.结果表明,模拟FL+3亚区具有较好的低温韧性,其冲击断口形貌均为大量的韧窝.然而随着热输入增加,其冲击吸收功降低,10 kJ/cm、15 kJ/cm、30 kJ/cm和45 kJ/cm不同热输入下的-196℃冲击吸收功分别为177 J、172 J、138 J和112J.FL+3亚区的显微组织为单相奥氏体组织,随着热输入增加,晶粒尺寸无明显变化,而小角度晶界比例升高.热输入增加会加剧FL+3亚区的C、Cu晶界偏析和Mn带状偏析,提高偏析区域的层错能以及临界剪切孪晶应力,使得孪生机制难以激活,进而减弱了形变孪晶的韧化作用,降低低温韧性.当热输入增大到15 kJ/cm时,FL+3亚区开始析出尺寸约为200 nm的颗粒状和块状Cr_(23)C_(6)碳化物,且析出相的尺寸和数量随着热输入增加而进一步增加.碳化物析出易引起应力集中而产生裂纹萌生,降低了FL+3亚区的低温韧性. 展开更多
关键词 高锰钢 热输入 焊接热模拟 晶界比例 偏析 析出相 低温韧性
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Aerodynamic, Kinematic and Control Coupling Simulation of Aircraft Maneuvering Flight
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作者 Haohui Tang Shuanghou Deng 《World Journal of Engineering and Technology》 2024年第4期1126-1145,共20页
Aiming at the high angle of attack pull-up and multi-channel roll pull-up coupling problems of high maneuvering aircraft, this paper establishes the flight attitude control rate by means of unsteady flow numerical sol... Aiming at the high angle of attack pull-up and multi-channel roll pull-up coupling problems of high maneuvering aircraft, this paper establishes the flight attitude control rate by means of unsteady flow numerical solution, dynamic unstructured nested mesh assembly method and numerical solution method of flight mechanics equation. On this basis, a virtual flight simulation platform integrating pneumatics, motion and control is established. Based on this virtual flight simulation platform, F-16 aircraft is simulated by high angle of attack pull-up flight mode and multi-channel roll pull-up coupling flight mode. Finally, the influence of rudder on the yaw control channel is investigated. The results show that the numerical virtual flight simulation platform established in this paper has the ability to simulate maneuvering flight of aircraft. 展开更多
关键词 High Angle of Attack Pull-Up High Maneuvering Aircraft Flight Attitude Control Rate Dynamic Unstructured Nested Mesh Virtual Flight Simula-tion Platform
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出生体质量、妊娠日龄和世代间隔对奶牛泌乳性能的影响
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作者 杨阳 王煜舒 +3 位作者 叶翠芳 李广 周彬 欧四海 《养殖与饲料》 2025年第1期1-4,共4页
[目的]为充分发挥青年牛产犊后的产奶潜力,研究出生、配种及妊娠等不同阶段对其产后泌乳性能的影响。[方法]2021年1月—2023年12月收集新疆石河子2个规模化奶牛场中青年牛出生日期、配种日期、妊娠日期、产犊和所产犊牛体质量以及产后... [目的]为充分发挥青年牛产犊后的产奶潜力,研究出生、配种及妊娠等不同阶段对其产后泌乳性能的影响。[方法]2021年1月—2023年12月收集新疆石河子2个规模化奶牛场中青年牛出生日期、配种日期、妊娠日期、产犊和所产犊牛体质量以及产后产奶量等信息,分析青年牛出生体质量、妊娠日期、世代间隔等因素与其产后泌乳性能的相关性。[结果]青年牛的出生体质量、配种体质量及妊娠日龄和世代间隔等因素均对其产后泌乳性能均产生显著影响,呈正相关(P<0.05)。出生体质量在37 kg以上、配种体质量达到410 kg,妊娠日龄超过438 d以及世代间隔711.16 d以上的青年母牛产后头胎次泌乳量相对较高。[结论]应加强青年母牛妊娠期的营养管理,同时合理控制配种体质量和妊娠时间,并优化世代间隔。 展开更多
关键词 荷斯坦青年牛 出生体质量 配种 妊娠日龄 世代间隔 泌乳量 营养管理
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教育强国背景下职普融通的理论审视与思考——2024年职普融通研究与实践新进展
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作者 刘晓 张子益 《中国职业技术教育》 北大核心 2025年第2期31-38,共8页
职普融通作为国家教育改革的重要命题,始终受到教育研究者的关注。通过梳理2024年职普融通相关研究文献发现,已有研究主要聚焦六个关键问题,即职普融通的时代内涵,中等职业教育的合法性,综合高中建设,职普融通的国际经验借鉴,职普融通... 职普融通作为国家教育改革的重要命题,始终受到教育研究者的关注。通过梳理2024年职普融通相关研究文献发现,已有研究主要聚焦六个关键问题,即职普融通的时代内涵,中等职业教育的合法性,综合高中建设,职普融通的国际经验借鉴,职普融通实践困境,职普融通政策优化。围绕上述关键问题,研究者们达成以下共识:一是将“职普融通”作为一个整体概念进行深化解读,明确职普融通在教育强国建设中的战略意义;二是坚持中等职业教育基础地位不动摇,稳步推进职普融通试点工作;三是强化地方党委、政府高位推动的主体责任,加强多部门协同推进职普融通。 展开更多
关键词 职业教育 职普融通 职业教育体系 中等职业教育 综合高中 科研综述
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Fixation and Creep of Compressed Wood of Chinese Fir Irradiated with Gamma Rays 被引量:1
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作者 王洁瑛 赵广杰 《Forestry Studies in China》 CAS 2001年第1期58-65,共8页
In order to discuss the mechanisms of permanent fixation of wood compression set , compressed wood of Chinese fir (Cunninghamia lanceolata) was irradiated by gamma rays from 60 Co. The irradiation doses wer... In order to discuss the mechanisms of permanent fixation of wood compression set , compressed wood of Chinese fir (Cunninghamia lanceolata) was irradiated by gamma rays from 60 Co. The irradiation doses were 0 (for match specim ens), 10 3, 5×10 3, 10 4, 5×10 4, 10 5, 5×10 5, 10 6, 5×10 6 Gy, res pectively. Then the weight loss, the equilibrium moisture content (EMC), the rec overy of wood compression set after adsorption (RSA) and the recovery after imme rsion in water (RSW), as well as the creep behaviour under a dry specimen condit ion and under an adsorption and subsequent desorption condition were measured an d discussed. This research proves that the doses of gamma irradiation have great effect on weight loss, EMC, RSA, RSW of irradiated compressed wood of Chinese f ir. The weight loss and the EMC increase, the RSA and the RSW fall drastically w hen the irradiation doses exceed 10 6 Gy. Both the instantaneous compliance and the creep compliance of the irradiated specimens under the two measurement cond itions show the general trend of increase with the increase of gamma irradiation doses. It can be deduced that decomposition or decrystallization reactions happ en in the wood cell wall at high gamma irradiation doses, especially at doses of around 5×10 6 Gy. In addition, this research proves that decomposition of mai n components of cell wall of compressed wood will lead to fixation of compressio n set of wood to a certain degree. 展开更多
关键词 gamma irradiation compressed wood Chinese fir fixa tion CREEP
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Determination of Heavy Metals in Dendrobium candidium Wall.ex Lindl.by ICP-MS 被引量:3
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作者 郑龙 杨春亮 +1 位作者 苏子鹏 叶剑芝 《Agricultural Science & Technology》 CAS 2015年第12期2592-2595,共4页
[Objective] This research aimed to establish an inductively coupled plasma mass spectrometry (ICP-MS) method for determination of five kinds of heavy metals (Pb, Cd, Cu, As and Hg) in Dendrobium candidium Wall. ex... [Objective] This research aimed to establish an inductively coupled plasma mass spectrometry (ICP-MS) method for determination of five kinds of heavy metals (Pb, Cd, Cu, As and Hg) in Dendrobium candidium Wall. ex Lindl. [Method] The samples were digested in HNO3-H202 acids system by closed vessel microwave di- gestion. At the same time, internal standard was added to avoid the matrix effect. [Result] The five kinds of heavy meals all showed good linear relationships, and the correlation coefficients ranged from 0.998 2 to 0.999 9. The detection limits of the five kinds of heavy metals were in the range of 0.008-0.750 μg/L, while the stan- dard recovery rates were in the range of 90.4%-96.9%. The relative standard devi- ations ranged from 1.6% to 8.2%. The heavy metals in the Ginseng and Astragalus national standard samples were determined by the established ICP-MS method, and the results were in conformity with the standard values. [Conclusion] The established method has simple and convenient operation and accurate and reliable results, and it meets the requirements by determination of heavy metals in Dendrobium candididium Wall. ex Lindl. 展开更多
关键词 Dendrobium candidium Wall. ex Lindl. Heavy metals Microwave diges- tion ICP-MS
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基于论元结构和论元角色的英语-(a)tion型后缀动词名物词具体义研究 被引量:7
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作者 双文庭 夏子宜 马阳 《天津外国语大学学报》 2015年第3期9-14,共6页
英语双音节和多音节及物动词大多可以通过添加-(a)tion或同类后缀的形式构成相应的动词名物词。宏观上讲,这类词有具体和抽象两种意义,抽象义往往和原动词的意义十分接近,表示动作或行为本身,而具体义则可从相应动词的论元结构和论元角... 英语双音节和多音节及物动词大多可以通过添加-(a)tion或同类后缀的形式构成相应的动词名物词。宏观上讲,这类词有具体和抽象两种意义,抽象义往往和原动词的意义十分接近,表示动作或行为本身,而具体义则可从相应动词的论元结构和论元角色来找到语义依据。具体来说,具体义往往可以通过原动词论元结构中的某一论元或其上位词来表达。英语这类名物词的具体义与相应动词论元的这种内在关系的形成,与动词词义本身以及人类的认知规律均有重要联系。 展开更多
关键词 论元结构 论元角色 -(a)tion型后缀 动词名物词 具体义
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Standard Operating Procedure of Houttuynia cordata Thunb.Plastic Greenhouse Cultivation 被引量:1
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作者 钟军 戴林建 《Agricultural Science & Technology》 CAS 2016年第7期1571-1576,共6页
This standard operating procedure stipulated the natural condition of pro- ducing area, cultivation technique, disease and pest control, harvest, quality stan- dard, packaging, transportation and storage of H. cordata... This standard operating procedure stipulated the natural condition of pro- ducing area, cultivation technique, disease and pest control, harvest, quality stan- dard, packaging, transportation and storage of H. cordata, in order to provide a ba- sis for the standard cultivation of H. cordata. 展开更多
关键词 Houttuynia cordata l'hunb Plastic Greenhouse Standardization produc- tion Standard Operating Procedure
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Identification and Cu Enrichment Capacity of TLSB_2-K, a Cu-tolerant Strain 被引量:1
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作者 康薇 郑进 《Agricultural Science & Technology》 CAS 2014年第12期2081-2084,2144,共5页
[Objective] The Cu-tolerance and Cu enrichment capacity of TLSB2-K were investigated. [Method] The previously isolated TLSB2-K strain was identified though morphological observation, gram staining and 16S rDNA sequenc... [Objective] The Cu-tolerance and Cu enrichment capacity of TLSB2-K were investigated. [Method] The previously isolated TLSB2-K strain was identified though morphological observation, gram staining and 16S rDNA sequence alignment. In ad- dition, the effects of temperature, pH and osmotic pressure on the growth of strain were also investigated by using shaking culture. The Cu-tolerance and Cu enrich- ment capacity of TLSB2-K strain under Cu stress were also studied. [Result] The results showed TLSB2-K belongs to Bacillus spp., and its optimum growth conditions were as follows: temperature, 27 ~C; pH, 7.0; osmotic pressure, 1.1% NaCI. When the Cu concentration ranged from 100 mg/L to 500 mg/L, the strain grew well; when the Cu concentration ranged from 100 mg/L to 400 mg/L, the Cu content in bacteria was increased with the increase of Cu concentration; when the Cu con- centration was 400 mg/L and the incubation time was 30 h, the Cu content in bac- teria reached the peak (2 250 mg/kg); the highest tolerant concentration was 700 mg/L. [Conclusion] TLSB2-K strain had relatively high Cu tolerance and Cu enrich- ment capacity. They had important theoretical research and engineering application values. 展开更多
关键词 Soil contamination Cu tolerance Bacillus cereus Molecular identifica- tion Enrichment capacity
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表面印迹微球在水相介质样品前处理中的应用研究进展
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作者 王思涛 刘智敏 许志刚 《分析测试学报》 CAS 北大核心 2025年第1期61-72,共12页
氢键通常是分子印迹聚合物识别模板分子的主要机制,由于水分子等诸多影响因素带来的干扰,有效识别水环境中的分析物一直是分子印迹技术面临的一大挑战。表面印迹微球具有比表面积大和易于修饰等特性,能够被灵活运用以满足各种水相样品... 氢键通常是分子印迹聚合物识别模板分子的主要机制,由于水分子等诸多影响因素带来的干扰,有效识别水环境中的分析物一直是分子印迹技术面临的一大挑战。表面印迹微球具有比表面积大和易于修饰等特性,能够被灵活运用以满足各种水相样品前处理的需求,是克服水相识别困难的有效方法之一。该文综述了近年来水相识别表面印迹微球的各种制备策略及其代表性应用,包括不同基底、亲水性识别、非氢键的协同识别和基于特殊组件的表面印迹微球;从作用力和识别机制层面讨论了在水相介质中识别分子时的干扰因素及其调控策略,并进一步介绍了表面印迹微球在水相样品前处理中的应用;最后探讨了表面印迹微球在水相样品前处理领域面临的挑战及未来研究趋势。 展开更多
关键词 表面印迹微球 水相识别 样品前处理 制备策略
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Research Progress and Identification Method of Apple Stress Resistance
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作者 王贵平 王金政 +2 位作者 薛晓敏 路超 聂佩显 《Agricultural Science & Technology》 CAS 2013年第10期1413-1416,共4页
In the research, changes of apple chemistry, and molecule, under stresses, are n terms of morphology, physiology, bio- illustrated and research and identifica- tion methods of apple resistance are explored involving ... In the research, changes of apple chemistry, and molecule, under stresses, are n terms of morphology, physiology, bio- illustrated and research and identifica- tion methods of apple resistance are explored involving drought-resistance, flood-re- sistance, salt-stress resistance, cold-hardiness and heat-resistance. In addition prospects of apple resistance research are proposed, as well. 展开更多
关键词 APPLE Adverse stress Stress resistance Research progress Identifica- tion method
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GeoStation地质外业系统研究与应用 被引量:9
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作者 唐海涛 王国光 卓胜豪 《人民长江》 北大核心 2017年第15期46-49,共4页
针对目前地质勘察人员野外数据处理广泛采用的"铅笔+记录纸"的作业方式,开发了一种基于移动终端的地质外业系统,旨在帮助地质勘察人员实现地质外业数据采集的信息化。通过将已整理入库的数据离线存储至移动终端并携带到勘察现... 针对目前地质勘察人员野外数据处理广泛采用的"铅笔+记录纸"的作业方式,开发了一种基于移动终端的地质外业系统,旨在帮助地质勘察人员实现地质外业数据采集的信息化。通过将已整理入库的数据离线存储至移动终端并携带到勘察现场,实现查阅和及时更新;并在数据采集完成后在线上传至服务器。该研究改变了传统野外数据记录中"铅笔+记录纸"的作业方式,对于实现地质勘察工作电子化,减少重复工作量,提高数据采集、整理效率具有重要的意义。工程应用结果表明,该系统大大提高了地质勘察工作效率,具有广阔的应用前景。 展开更多
关键词 地质外业系统 移动终端 地质信息化
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Study on Growth and Development and Dry Matter Production of Greenhouse Tomato in North China
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作者 王停停 温祥珍 +2 位作者 张玲 袁婷婷 李亚灵 《Agricultural Science & Technology》 CAS 2016年第7期1638-1641,1713,共5页
[Objective] This study aimed to investigate the growth and development and dry matter production and allocation of greenhouse tomato in North China. [Method] With tomato cultivar 'Jinguo No.l' as the experimental ma... [Objective] This study aimed to investigate the growth and development and dry matter production and allocation of greenhouse tomato in North China. [Method] With tomato cultivar 'Jinguo No.l' as the experimental material, the ex- periments were conducted in a solar greenhouse located in Taigu, Shanxi (37o25' N, 112o25' E) from March to July, in 2014 and 2015. [Result] The plant height, leaf number, leaf area and dry matter production of greenhouse tomato increased lin- early with the increased days after transplantation, and their growth rates were 2.74 cm/d, 0.32 leaf/d, 70 cm2/d and 9.4 g/(m2.d), respectively. The fruit dry weight also showed a linear relationship with the plant dry weight. After fruit setting, the fruit dry weight was increased by about 0.69 g when the plant dry weight was increased by 1 g. The allocation proportions of dry matter in tomato roots, stems and leaves de- clined significantly from plant flowering to fruiting, while the proportion of fruit dry weight in plant dry weight increased significantly, exceeding 60%. There was a strong linear relationship between dry matter production of tomato and effective cu- mulative temperature (sum of temperature higher than 10 ^(3) in the solar green- house, and the dry matter production was increased by about 0.73 g/m2 when the effective cumulative temperature was increased by one unit. The dry matter produc- tion of tomato plant also showed a strong linear relationship with photosynthetic ac- tive radiation (PAR) in the greenhouse, and about 3.4 g of dry matter was synthe- sized per unit (M J) of PAR. [Conclusion] Extending the growing period and improv- ing the temperature and light conditions could increase the dry matter production of tomato. 展开更多
关键词 Solar greenhouse TOMATO Growth and development Dry matter alloca- tion
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Comparions of Required Nitrogen Fertilizers by Hybrid Cultivar and Conventional Cultivar of Rapeseed(Brassica napus L.)
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作者 李银水 余常兵 +4 位作者 谢立华 胡小加 秦璐 廖祥生 廖星 《Agricultural Science & Technology》 CAS 2015年第10期2231-2237,共7页
[Objective] The aim of this study was to understand the difference of N fertilizer requirement between hybrid rapeseed and conventional rapeseed. [Method] Two hybrid cultivars, ZY5628 and ZY7819, and the conventional ... [Objective] The aim of this study was to understand the difference of N fertilizer requirement between hybrid rapeseed and conventional rapeseed. [Method] Two hybrid cultivars, ZY5628 and ZY7819, and the conventional cultivar ZS10, were compared through two field experiments. In Experiment 1, seed yield and optimum N application rate were assessed in the field with five N application treatments. In Expedment 2, N was applied uniformly at 180 kg/hm2, and plant biomass and N accumulation were measured at several developmental stages, while N use efficien- cy was calculated for rape at maturity. [Results] The experiment 1 results showed that seed yields of ZY5628 and ZY7819 were both significantly higher than that of ZS10, and compared to ZS10, optimum yield (plateau yield) was higher by 18.7% and 20.2%, while the recommended N application rate was lower by 9.5% and 9.6% for ZY5628 and ZY7819, respectively. The experiment 2 results showed that during vegetative development, all three cultivars exhibited similar accumulations of plant biomass and N, but through flowering and maturity ZY5628 and ZY7819 pro- duced more biomass, acquired more N, and utilized acquired N more efficiently to- wards seed production than ZS10. [Conclusion] With equivalent inputs, the hybrid rapeseed cultivars ZY5628 and ZY7819 tested herein yield more seed with higher N use efficiency than the conventional rapeseed ZS10. This information will be valu- able for growers seeking to improve efficiency while reducing costs of rape production in China. 展开更多
关键词 Rapeseed (Brassica napus. L) Hybrid cultivars Yield Nitrogen applica- tion rate Nitrogen use efficiency
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Effect of Cultivation Conditionss on Quality Parameters of High Grade Hybrid Rape of Brassica napus L.
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作者 赵继献 任廷波 程国平 《Agricultural Science & Technology》 CAS 2013年第1期59-68,共10页
[Objective] This study aimed to investigate the combined effects of sowing date, plant density, nitrogenous fertilizer, phosphorus fertilizer and potassium fertilizer on quality parameters of high grade hybrid rapesee... [Objective] This study aimed to investigate the combined effects of sowing date, plant density, nitrogenous fertilizer, phosphorus fertilizer and potassium fertilizer on quality parameters of high grade hybrid rapeseed. [Method] By using Youyan 599 and Sanbei 98 as experimental materials, quadratic orthogonal rotation combination with five factors was designed for this study. [Result] Erucic acid content was nega- tively correlated with sowing date and nitrogen fertilizer, positively correlated with plant density. Glucosinolate content was negatively correlated with sowing date, positively correlated with potash fertilizer amount. Oil content was negatively correlated with sowing date and nitrogen fertilizer amount, positively correlated with plant density and potash fertilizer amount. Protein content was positively correlated with sowing date and nitrogen fertilizer amount, negatively correlated with plant density and potash fer- tilizer amount. Oleic acid content was negatively correlated with phosphate fertilizer amount, positively correlated with nitrogen fertilizer amount. Palmitic acid was nega- tively correlated with potash fertilizer amount, positively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Youyan 599, but negatively correlated with sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount in Sanbei 98. Stearic acid content was posi- tively correlated with sowing date, plant density, nitrogen fertilizer amount and phos- phate fertilizer amount. Linoleic acid was positively correlated with density and nitroge- nous fertilizer, but negatively correlated with potash fertilizer amount. Linolenic acid was positively correlated with nitrogen fertilizer amount and potash fertilizer amount. Eicosenoic acid was negatively correlated with sowing date. There were positive cor- relations and negative correlations among cultivation conditions and quality parame- ters, and the positive correlations and negative correlations could counteract each other. Expression of quality parameters for each treatment was the combined effect. Among the 50 pairs of simple correlations of five cultivation factors and ten quality parameters, 26 pairs were consistent between two varieties, 24 pairs of simple corre- lation were not. Sowing date, plant density, nitrogen fertilizer amount and phosphate fertilizer amount showed significant influence on erucic acid of two varieties, but small effect on palmitic acid. [Conclusion] The combined effect of the five cultivation factors could not fundamentally improve the quality traits of high grade hybrid rapeseed. 展开更多
关键词 Hybrid rapeseed Cultivation factor Quality parameters Orthogonal rota- tion combination design EFFECT
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