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Warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography
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作者 Pengyu Hu Jiangpeng Wu +3 位作者 Zhengang Yan meng he Chao Liang Hao Bai 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期162-172,共11页
High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high efficiency.However,it... High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high efficiency.However,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment swarm.To address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography.Firstly,background difference algorithm is utilized to extract the center and area of each fragment in the image sequence.Subsequently,a multi-object tracking(MOT)algorithm using Kalman filtering and Hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment swarm.To reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial fitting.Finally,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10^(3)fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%. 展开更多
关键词 Warhead fragment measurement High speed photography Stereo vision Multi-object tracking Spatio-temporal reconstruction
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新时代民族中小学教研工作实践探究——以吉林省教育学院民族中小学教研工作开展为例
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作者 孟和 《吉林省教育学院学报》 2025年第3期7-11,共5页
中共中央国务院《关于深化教育教学改革全面提高义务教育质量的意见》中明确指出要“发挥教研支撑作用”“加强和改进新时代教研工作,理顺教研管理体制”;教育部《关于加强和改进新时代基础教育教研工作的意见》中强调“教研工作是保障... 中共中央国务院《关于深化教育教学改革全面提高义务教育质量的意见》中明确指出要“发挥教研支撑作用”“加强和改进新时代教研工作,理顺教研管理体制”;教育部《关于加强和改进新时代基础教育教研工作的意见》中强调“教研工作是保障基础教育质量的重要支撑”“要进一步明确教研机构的工作职责,充分发挥教研机构在推进区域课程教学改革、教学诊断与改进、课程教学资源建设、培育推广优秀教学成果等方面的重要作用”。 展开更多
关键词 吉林省教育学院 民族中小学教研 新时代
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寄生疫霉侵染对不同类型烟草根系酶活性和内源激素的影响
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作者 刘昱彤 孙明铭 +7 位作者 王蕾 姜自鹏 王芳娟 刘洪泰 孙滢 官宇 孟鹤 程立锐 《分子植物育种》 北大核心 2025年第5期1558-1563,共6页
为研究烟草抗、感材料与寄生疫霉互作过程中相关防御酶活性以及内源激素含量的变化,了解烟草抗黑胫病的抗性机制。选用烟草抗病品种Beinhart1000-1(BH)和感病品种‘小黄金1025’(XHJ),分别接种寄生疫霉(Phytophthora nicotianae),检测... 为研究烟草抗、感材料与寄生疫霉互作过程中相关防御酶活性以及内源激素含量的变化,了解烟草抗黑胫病的抗性机制。选用烟草抗病品种Beinhart1000-1(BH)和感病品种‘小黄金1025’(XHJ),分别接种寄生疫霉(Phytophthora nicotianae),检测接种前及接种后6、12、24和60 h烟苗根部过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、苯丙氨酸解氨酶(PAL)和脂氧合酶(LOX)活性及过氧化氢(H_(2)O_(2))、茉莉酸(JA)、水杨酸(SA)含量的变化。结果显示,在整个侵染过程中,抗病品种BH的酶活性变化及激素含量的变化均强于感病品种XHJ。两个品种H_(2)O_(2)含量总体呈先上升再下降的趋势,BH中的H_(2)O_(2)水平持续高于XHJ;BH中的SA及JA含量在接种后6 h显著上调,均早于XHJ;LOX酶活性变化趋势与JA含量变化趋势呈正相关,PAL酶活性变化趋势与SA含量变化趋势呈正相关。本研究为阐明烟草应答寄生疫霉侵染的抗性机制提供了理论依据。 展开更多
关键词 烟草 寄生疫霉 烟草黑胫病 酶活性 内源激素
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PVA-g-PDLA的合成及其对PLLA/PVA共混物的改性研究
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作者 蒙赫 姜丽 +1 位作者 张凯 杨鸣波 《中国塑料》 北大核心 2025年第10期6-11,共6页
左旋聚乳酸(PLLA)因其优异的环保性、加工性以及力学性能而被广泛关注。然而,PLLA较低的韧性和熔体强度极大限制了其作为吹塑薄膜材料。为解决该问题,本文首先利用右旋聚乳酸(PDLA)与聚乙烯醇(PVA)反应,成功合成了接枝共聚物PVA-g-PDLA... 左旋聚乳酸(PLLA)因其优异的环保性、加工性以及力学性能而被广泛关注。然而,PLLA较低的韧性和熔体强度极大限制了其作为吹塑薄膜材料。为解决该问题,本文首先利用右旋聚乳酸(PDLA)与聚乙烯醇(PVA)反应,成功合成了接枝共聚物PVA-g-PDLA,并将其通过直接熔融共混法和母料熔融共混法与PLLA/PVA进行共混。研究了直接法和母料法制备的PLLA/PVA/PVA-g-PDLA共混物结晶性能、流变特性、松弛行为和冲击性能。结果表明,相比于直接法,母料法制备的PLLA/PVA/PVA-g-PDLA共混物中形成了数量更多、尺寸更小的立构复合晶(SC晶),显著提高了共混材料的熔体强度,改善其松弛行为,促使其在180℃下的特征松弛时间增加,并且在熔体拉伸流变中表现出了明显的拉伸硬化现象。此外,母料法制备的PLLA/PVA/PVA-g-PDLA共混材料具有更好的冲击韧性,其冲击强度达到了6.03 kJ/m^(2),分别为纯PLLA和直接法制备的PLLA/PVA/PVA-g-PDLA的3.8倍和2.5倍。 展开更多
关键词 聚乳酸 聚乙烯醇 接枝聚合物 熔体强度 冲击韧性
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煤矿机电技术管理在煤矿安全生产中的应用 被引量:1
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作者 张帅 全亚鹏 +3 位作者 孟和 李瑞 张学谦 周伟 《价值工程》 2025年第10期151-154,共4页
随着机电技术的不断发展,煤矿机电设备已经成为煤矿生产中不可或缺的重要装备,而煤矿机电技术管理的应用,可以大幅度提高生产效率,降低故障发生率,从根本上确保煤矿工作能够安全稳定进行。因此,应当针对煤矿机电技术管理在煤矿安全生产... 随着机电技术的不断发展,煤矿机电设备已经成为煤矿生产中不可或缺的重要装备,而煤矿机电技术管理的应用,可以大幅度提高生产效率,降低故障发生率,从根本上确保煤矿工作能够安全稳定进行。因此,应当针对煤矿机电技术管理在煤矿安全生产中的应用进行深入分析。 展开更多
关键词 煤矿 机电技术管理 安全生产
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一测多评法同时测定蒙药扎冲十三味丸中6个生物碱成分
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作者 包红英 周钰坤 +4 位作者 陈紫薇 嵇增云 孟和 郝俊生 辛颖 《中国药品标准》 2025年第2期190-197,共8页
目的:建立HPLC一测多评法(QAMS)同时测定扎冲十三味丸(ZSP)中苯甲酰新乌头原碱、苯甲酰乌头原碱、苯甲酰次乌头碱、新乌头碱、次乌头碱和乌头碱等6个生物碱成分,并验证该方法在ZSP质量分析中应用的可行性。方法:采用C 18色谱柱,流动相为... 目的:建立HPLC一测多评法(QAMS)同时测定扎冲十三味丸(ZSP)中苯甲酰新乌头原碱、苯甲酰乌头原碱、苯甲酰次乌头碱、新乌头碱、次乌头碱和乌头碱等6个生物碱成分,并验证该方法在ZSP质量分析中应用的可行性。方法:采用C 18色谱柱,流动相为0.1 mol·L^(-1)醋酸铵(每1000 mL加冰醋酸0.5 mL)(A)-乙腈:四氢呋喃(25∶15)(B),梯度洗脱(0~50 min,18%B→28%B),检测波长为235 nm,流速为1.0 mL·min^(-1),柱温为40℃。以苯甲酰乌头原碱为内参物,建立与其他5种生物碱的相对校正因子(f s/i),采用f s/i计算各成分的质量分数,同时用外标法(ESM)测定,比较2种方法测定结果,评价QAMS在ZSP中应用的准确性。结果:ZSP中苯甲酰新乌头原碱、苯甲酰次乌头原碱、新乌头碱、次乌头碱和乌头碱5个生物碱成分的f s/i重现性良好,分别为0.6804、0.4506、0.8508、0.6761、和0.7570,QAMS与ESM测得结果无明显差别。结论:该方法简便、稳定、重复性良好,可用于ZSP中6个生物碱成分的质量控制。 展开更多
关键词 蒙药扎冲十三味丸 一测多评法 相对校正因子 苯甲酰新乌头原碱 苯甲酰次乌头原碱 苯甲酰乌头原碱 新乌头碱 次乌头碱 乌头碱
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基于碱性抑制的矿山帷幕注浆材料配比优化研究
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作者 薛晓峰 刘宏磊 +2 位作者 张帅 孟和 全亚鹏 《水文地质工程地质》 北大核心 2025年第4期159-167,共9页
某大水型金属矿山帷幕注浆工程中应用的黏土-水泥浆液水化反应后的pH值高达13,表现为强碱性,对地下水及地表水构成了潜在污染风险。为探究低碱性外加剂对该矿山水害防治帷幕注浆工程中黏土-水泥浆液性能的调控机制,采用正交试验设计,系... 某大水型金属矿山帷幕注浆工程中应用的黏土-水泥浆液水化反应后的pH值高达13,表现为强碱性,对地下水及地表水构成了潜在污染风险。为探究低碱性外加剂对该矿山水害防治帷幕注浆工程中黏土-水泥浆液性能的调控机制,采用正交试验设计,系统分析了不同配比条件下浆液的流变特性,包括流动性、泵送性能、凝结时间及pH值的变化规律。通过分别引入磷石膏、粉煤灰及降碱外加剂(substance of Jin Pin,SJP),探讨不同材料在降低浆液碱性方面的有效性。试验结果显示:磷石膏能够将浆液pH值有效降低至11,同时延长凝结时间;粉煤灰虽在降低浆液碱度方面效果有限,却改善了浆液的泵送性能并缩短了泵送期限;SJP外掺剂在降低p H值和延长泵送期方面表现突出,当掺量由2.5%增加至3.5%时,浆液pH值显著降低至8。基于试验数据,优化了SJP外掺剂-粉质黏土-磷石膏-水泥配方,并通过正交试验确定了最优配比:复合酸式盐0.5%、硫铝酸盐1.5%、磷石膏10.0%、黏土50.0%。该优化配方制备的浆液p H值降低至10,流动度保持在18~23 cm,泵送期延长至100~220 min,充分满足工程应用需求。研究结果可为帷幕注浆工程中通过控制浆液碱性减少环境污染提供了科学依据。 展开更多
关键词 低碱性外加剂 黏土-水泥浆液 流变特性 p H值调控 优化配方
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海陆风对胶东沿海城市臭氧污染的影响
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作者 魏巍 张玉卿 +4 位作者 方渊 孟赫 隋玟萱 兰培文 叶子恒 《环境科学研究》 北大核心 2025年第7期1485-1495,共11页
为探究海陆风对胶东沿海城市臭氧(O_(3))污染的影响,以青岛市为代表城市,基于2023年4-10月地面空气、气象自动监测站的连续观测数据,分析海陆风对O_(3)浓度时空分布的影响,探讨有、无海陆风日气象要素、O_(3)生成潜势以及本地生成与外... 为探究海陆风对胶东沿海城市臭氧(O_(3))污染的影响,以青岛市为代表城市,基于2023年4-10月地面空气、气象自动监测站的连续观测数据,分析海陆风对O_(3)浓度时空分布的影响,探讨有、无海陆风日气象要素、O_(3)生成潜势以及本地生成与外来传输对O_(3)浓度贡献等的差异。结果表明:①观测期间青岛市共有69 d海陆风日,占比为35.9%,主要分布在7-10月。②海陆风日O_(3)日最大8 h平均浓度(O_(3)-8 h浓度)的平均值(140μg/m^(3))明显高于无海陆风日(127μg/m^(3));相较于无海陆风日,海陆风日青岛市各点位O_(3)-8 h浓度平均值升高了3~23μg/m^(3),尤其是南部沿海点位表现更为明显。③海陆风日O_(3)最大小时生成速率[49.66μg/(m^(3)·h)]及日间O_(3)生成速率平均值[26.38μg/(m^(3)·h)]均高于无海陆风日。高温、低湿、强太阳辐射以及静稳的气象条件促进了海陆风日O_(3)的光化学生成和污染累积。海陆风日影响O_(3)生成的主要VOCs来源为机动车排放源、液化石油气和油气挥发源以及溶剂涂料使用源,其中以机动车排放源贡献率最大。④基于观测的模型(OBM)模拟结果显示,海陆风日06:00-08:00存在明显的外来传输影响,日均O_(3)本地生成和外来传输贡献率分别为85.1%和14.9%。日间尤其是上午时段较高的本地生成,加之早间外来传输进一步抬升了O_(3)的本底浓度,这是海陆风日O_(3)-8 h浓度较高的主要原因。研究显示,海陆风日O_(3)污染以本地生成为主,同时也受外来传输影响,因此在加强本地重点VOCs源管控的同时,也应注重区域联防联控,从而实现空气质量的持续改善。 展开更多
关键词 海陆风 O_(3)污染 O_(3)生成潜势 基于观测的模型(OBM) 沿海城市
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基于客观环流分型的青岛市臭氧污染特征及潜在源区
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作者 薛莲 张玉卿 +4 位作者 孟赫 于慧珍 方渊 刘岳峰 韩矗 《环境科学学报》 北大核心 2025年第7期66-77,共12页
利用旋转T-mode主成分分析法(PCT)对青岛及周边区域海平面气压场等进行客观分型,并结合同期地面观测资料研究不同天气类型和气象要素对O_(3)浓度的影响,以服务O_(3)浓度预报和精细化管控工作.结果表明,2019—2023年,青岛市O_(3)年评价... 利用旋转T-mode主成分分析法(PCT)对青岛及周边区域海平面气压场等进行客观分型,并结合同期地面观测资料研究不同天气类型和气象要素对O_(3)浓度的影响,以服务O_(3)浓度预报和精细化管控工作.结果表明,2019—2023年,青岛市O_(3)年评价浓度范围为144~169μg·m^(-3),2021年最低,2023年最高;O_(3)日最大8 h浓度范围为10~258μg·m^(-3),其中,污染日共计146 d,集中出现在4—11月,5、6月居多.污染天气型中,O_(3)污染日500 hPa位势高度受西风槽后西北气流影响,850 hPa位势高度受暖区控制,近地面受东北低压槽影响,以西南风为主,且伴随高温、强太阳辐射、弱风、较低相对湿度等典型特征;气流轨迹主要为来自安徽北部和江苏北部的西南气流,潜在源区主要为青岛周边及南部区域.非污染天气型中,高空以槽后西北气流、槽底偏西气流为主,近地面主要为冷高压前部、高压中心北部和东北低压底部. 展开更多
关键词 O_(3)污染 环流分型 后向轨迹 潜在源区 青岛市
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Electrostatic discharge in powder-storage silos:Frequency and energy analysis under various conditions
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作者 ZHANG Gaoqiang LI Liangliang +4 位作者 LIANG Cai meng he LAN Qi CheN Xiaoping MA Jiliang 《Journal of Southeast University(English Edition)》 2025年第1期101-108,共8页
To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency... To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency,and energy are investigated for powders of different polarities.Although the powders have low charge-to-mass ratios(+0.087μC/kg for the positively charged powders and−0.26μC/kg for the negatively charged ones),electrostatic discharges occur approximately every 10 s,with the maximum discharge energy being 800 mJ.Powder polarity considerably influences discharge energy.The positive powders exhibit higher discharge energy than the negative ones,although discharge frequency remains similar for both.Effects of powder charge,humidity,and mass flow on discharge frequency and discharge energy are quantitatively analyzed,providing important insights for the improvement of safety in industrial powder handling. 展开更多
关键词 electrostatic discharge POWDER charge-to-mass ratio discharge frequency SILO
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1Cr17Ni9Ti∕Q235复合板矫直过程数值模拟与压下参数分析 被引量:2
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作者 孟贺 李秋鹤 +1 位作者 付颖 廖桂兵 《机械设计》 CSCD 北大核心 2024年第7期143-149,共7页
双金属复合板会受到材料间产生不同程度的热残余应力的影响,导致板型缺陷,需要进行矫直。为了研究不同压下倾角参数对复合板矫直效果的影响,文中采用数值模拟方法研究了在0.43°,0.33°和0.23°这3种不同压下倾角矫直方案下... 双金属复合板会受到材料间产生不同程度的热残余应力的影响,导致板型缺陷,需要进行矫直。为了研究不同压下倾角参数对复合板矫直效果的影响,文中采用数值模拟方法研究了在0.43°,0.33°和0.23°这3种不同压下倾角矫直方案下,1Cr17Ni9Ti∕Q235复合钢板矫直过程中各方向的应力极值情况,以及矫直后的复合板纵向残余应力分布、平直度及等效塑性应变情况。结果表明:在矫直过程中复合板的纵向应力极值最大且其差值也是最大;在压下倾角1,2,3矫直方案下,复合板的平直度值分别为0.19%,0.30%及0.23%;在3种不同压下倾角矫直方案下,对1Cr17Ni9Ti∕Q235复合钢板进行现场矫直试验,得到的复合板平直度结果与数值模拟结果几乎一致。在3种压下倾角矫直方案下1Cr17Ni9Ti∕Q235复合钢板等效塑性应变值分别为0.14,0.23及0.17。可见压下倾角的大小影响复合板矫直后的平直度,压下倾角方案1的复合板的矫直效果最好。 展开更多
关键词 复合板 矫直 数值模拟 压下倾角 残余应力
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Indocyanine Green Nanoparticles for Theranostic Applications 被引量:13
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作者 Zonghai Sheng Dehong Hu +3 位作者 Miaomiao Xue meng he Ping Gong Lintao Cai 《Nano-Micro Letters》 SCIE EI CAS 2013年第3期145-150,共6页
Theranostics is a concept that integrated imaging and therapy. As an emerging field, it embraces multiple techniques to arrive at an individualized treatment purpose. Indocyanine green(ICG) is a near infrared dye that... Theranostics is a concept that integrated imaging and therapy. As an emerging field, it embraces multiple techniques to arrive at an individualized treatment purpose. Indocyanine green(ICG) is a near infrared dye that has been approved by Food and Drug Administration(FDA) in USA for the use in indicator-dilution studies in humans. ICG nanoparticles(NPs) have attracted much attention for its potential applications in cancer theranostics. This review focuses on the preparation, application of ICG NPs for in vivo imaging(fluorescent imaging and photoacoustic imaging) and therapeutics(photothermal therapy, photodynamic therapy and photoacoustic therapy), and future directions based on recent developments in these areas. It is hoped that this review might provide new impetus to understand ICG NPs for cancer theranostics. 展开更多
关键词 Indocyanine green(ICG) NANOPARTICLES THERANOSTICS CANCER
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Effect of the benzene ring of the dispersant on the rheological characteristics of coal-water slurry:Experiments and theoretical calculations 被引量:6
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作者 Lin Li Chuandong Ma +5 位作者 Shanpei Hu meng he Hao Yu Qingbiao Wang Xiaoqiang Cao Xiaofang You 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第3期515-521,共7页
In this study,low-rank coal-water slurry(LCWS)was prepared using polyoxyethylene dodecylphenol ether(PDPE)and polyoxyethylene lauryl ether(PLE),respectively.A combination of experiments and simulations was used to inv... In this study,low-rank coal-water slurry(LCWS)was prepared using polyoxyethylene dodecylphenol ether(PDPE)and polyoxyethylene lauryl ether(PLE),respectively.A combination of experiments and simulations was used to investigate the pulping properties and microscopic mechanism of the LCWS samples prepared using the two agents,so as to explore the influence of benzene ring on the performance of dispersant.The results of the LCWS preparation experiments revealed that the pulp-forming performance of PDPE exceeded that of PLE.When LCWS concentration is 62%,64%,and 66%,the apparent viscosity corresponding to PDPE is 247.80,504.17,and 653.10 mPa·s,and the apparent viscosity corresponding to PLE is 548.10,1470.61,and 1549.98 mPa·s,respectively.The C_(1000)(When the apparent viscosity is 1000 mPa·s,the corresponding concentration of LCWS is defined as C_(1000))values of PDPE and PLE are 67.60%and 62.95%,respectively.In addition to the van der Waals forces and hydrogen bonds between the PDPE and/or PLE molecules and coal,the benzene rings of PDPE presentπ-πstacking effect with the aromatic rings of coal.That could facilitate and strengthen the adsorption of PDPE on coal,which would be conducive to further improving the dispersion of coal particles.The two dispersants have no significant difference in effect on the pyrolysis of LCWS.The simulation results indicated that the times for PDPE and PLE molecules to reach flat adsorption state on coal are approximately 290 and 565 ps,respectively.The self-diffusion coefficient(D)of the PDPE and PLE on coal is 3.16 x 10^(-6)and6.57×10^(-6)m~2/s,respectively,and their interaction energies with coal are 785.71 and 648.60 kcal/mol,respectively.The results of the simulation calculations demonstrated that PDPE adsorbed on coal easier than PLE,and its binding is more stable than that of PLE owing to theπ-πstacking effect,which is conducive to uniform dispersion of coal in solution.The simulation results confirmed the experimental results. 展开更多
关键词 Low rank coal Low-rank coal-water slurry Benzene ring Molecular dynamics simulation
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Y_(2)O_(3)-functionalized graphene-immobilized Ni–Pt nanoparticles for enhanced hydrous hydrazine and hydrazine borane dehydrogenation 被引量:4
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作者 Qi-Lu Yao meng he +2 位作者 Ya-Ru Kong Tian Gui Zhang-Hui Lu 《Rare Metals》 SCIE EI CAS CSCD 2023年第10期3410-3419,共10页
Developing efficient and highly selective catalyst to promote hydrogen generation from hydrous hydrazine(N_(2)H_(4)·H_(2)O) and hydrazine borane(N_(2)H_(4)BH_(3))remains a challenging issue for fuel cell-based hy... Developing efficient and highly selective catalyst to promote hydrogen generation from hydrous hydrazine(N_(2)H_(4)·H_(2)O) and hydrazine borane(N_(2)H_(4)BH_(3))remains a challenging issue for fuel cell-based hydrogen economy.In this work,ultrafine and well-dispersed bimetallic NiPt nanoparticles(3.4 nm) were successfully immobilized on Y_(2)O_(3)-functionalized graphene(Y_(2)O_(3)/rGO) without any surfactant by a simple liquid impregnation approach.It is firstly found that integration of graphene and Y_(2)O_(3) not only can facilitate the formation of ultrafine NiPt nanoparticles(NPs),but also can effectively modulate the electronic structure of NiPt NPs,thereby boosting the catalytic performance.Compared with NiPt/Y_(2)O_(3) and NiPt/rGO,the NiPt/Y_(2)O_(3)/rGO nanocomposites(NCs) show remarkable enhanced catalytic efficiency for hydrogen production from N_(2)H_(4)-H_(2)O.In particular,the optimized Ni_(0.6)Pt_(0.4/)Y_(2)O_(3)/rGO NCs display the best catalytic efficiency and 100% H_(2) selectivity for N_(2)H_(4)-H_(2)O dehydrogenation,providing a turnover frequency(TOF) of2182 h^(-1) at 323 K,which is among the highest values ever reported.Moreover,the Ni_(0.6)Pt_(0.4)/Y_(2)O_(3)/rGO NCs also exhibit an excellent catalytic performance(TOF=3191 h^(-1)) and 100% H_(2) selectively for N_(2)H_(4)BH_(3)dehydrogenation at 323 K.The outstanding catalytic results obtained provide more possibilities for the potential applications of N_(2)H_(4)·H_(2)O and N_(2)H_(4)BH_(3) as promising chemical hydrogen storage materials. 展开更多
关键词 Hydrous hydrazine(N_(2)H_(4)·H_(2)O) Hydrazine borane(N_(2)H_(4)BH_(3)) DEHYDROGENATION GRAPHENE Catalysis
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Feasibility study on determining the conventional true value of gamma-ray air kerma in a minitype reference radiation 被引量:2
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作者 Yi-Xin Liu Biao Wei +5 位作者 Yang Xu meng he Ren-Hong Zhuo De-Zhi Wen Da-Jie Ding Ben-Jiang Mao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第6期133-139,共7页
A minitype reference radiation(MRR) with dimensions of only 1 m × 1 m × 1 m has been developed for the in situ calibration of photon dosimeters.The present work conducts a feasibility study on determining th... A minitype reference radiation(MRR) with dimensions of only 1 m × 1 m × 1 m has been developed for the in situ calibration of photon dosimeters.The present work conducts a feasibility study on determining the conventional true value of gamma-ray air kerma at the point of test in the MRR.Owing to its smaller dimensions,the scattered gamma-rays in the MRR are expected to induce a non-negligible interference with the radiation field compared with conditions in the standard reference radiation stipulated by ISO4037-1 or GB/T12162.1.A gamma-ray spectrometer was employed to obtain the spectra of scattered gamma-rays within the MRR,and the feature components of the spectra were extracted by principal component analysis to characterize the interference of a dosimeter probe in the radiation field.A prediction model of the CAK at the point of test was built by least squares support vector machine based on the feature component data obtained from nine sample dosimeters under five different dose rates.The mean prediction error of the CAK prediction model was within ±4.5%,and the maximum prediction error was about ±10%. 展开更多
关键词 Air kerma REFERENCE RADIATION Calibration Principal component analysis Support VECTOR machine
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One-pot synthesis of hexagonal NaLuF_(4):Yb,Er microcrystals with enhanced upconversion emission and high production yield 被引量:2
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作者 Xuesong Zhai Yin Li +3 位作者 Wei Zhao Wu Sun meng he Jing Feng 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第4期498-506,共9页
In this work,monodisperseβ-NaLuF_(4):Yb,Er microcrystals with intense upconversion emission were synthesized via a modified hydrothermal method.With the increase of reactant concentration,their production yield is in... In this work,monodisperseβ-NaLuF_(4):Yb,Er microcrystals with intense upconversion emission were synthesized via a modified hydrothermal method.With the increase of reactant concentration,their production yield is increased obviously,and the upconversion emission intensity inβ-NaLuF_(4):Yb,Er microcrystals is also enhanced significantly.The luminescence enhancement should be attributed to minimal internal OH defects,validated by a combination of analytical X-ray diffraction(XRD),energy dispersive spectrum(EDS),and Eu^(3+)structural probe measurements.We also reveal that high Na^(+):RE~(3+)ratio in theβ-NaLuF_(4):Yb,Er microcrystals prepared under Na^(~)+-rich reaction will arouse the increased repulsive energy ofβ-NaLuF_(4)microcrystals between F^(~)-and OH^(~)-anions and then facilitate the substitution of large OH^(-)ions by small F^(~)-ions under F^(~)--rich reaction conditions.Minimal OH^(-)concentrations can limit nonradiative relaxation and promote excitation energy harvesting for high upconversion efficiency.The presented results not only offer a facile method for the simultaneous production yield and luminescence intensity increase ofβ-NaREF_(4)microcrystals,but also uncover a better insight into the upconversion emission alterations,which is favorable to broaden their practical applications. 展开更多
关键词 β-NaLuF_(4):Yb Er microcrystals UPCONVERSION High reactant concentration Luminescence enhancement Internal OH~-defects High production yield
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Olanzapine Induces Inflammation and Immune Response via Activating ER Stress in the Rat Prefrontal Cortex 被引量:2
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作者 Wen-ting LI Xu-feng HUANG +4 位作者 Chao DENG Bao-hua ZHANG Kun QIAN meng he Tao-lei SUN 《Current Medical Science》 2021年第4期788-802,共15页
Objective Antipsychotics,in particular olanzapine,are first-line medications for schizophrenia.The prefrontal cortex(PFC)is an important region for antipsychotics’therapeutic effects.The PFC inflammatory and immune p... Objective Antipsychotics,in particular olanzapine,are first-line medications for schizophrenia.The prefrontal cortex(PFC)is an important region for antipsychotics’therapeutic effects.The PFC inflammatory and immune pathways are associated with schizophrenia pathogenesis.However,the effect of antipsychotics on the inflammatory and immune pathways in the PFC remains unclear.We aimed to examined the time-dependent effect of olanzapine on inflammatory and immune markers in the PFC of rats.Since the inflammatory and immune pathways are related to endoplasmic reticulum(ER)stress,we further investigated whether or not olanzapine-induced inflammation and immune responses were related to ER stress.Methods Expression of pro-inflammatory markers including IkappaB kinaseβ(IKKβ),nuclear factor kappa B(NFκB),tumor necrosis factorα(TNF-α),interleukin-6(IL-6)and IL-1β,and immune-related proteins including inducible nitric oxide synthase(iNOS),toll-like receptor 2(TLR2)and cluster of differentiation 14(CD14)were examined by Western blotting.Results Olanzapine treatments for 1,8 and 36 days significantly activated the inflammatory IKKβ/NFκB signaling,and increased the expression of TNF-α,IL-6,IL-1βand immune-related proteins such as iNOS,TLR4 and CD14.Olanzapine treatment for 1 day,8 and 36 days also induced ER stress in the PFC.Co-treatment with an ER stress inhibitor,4-phenylbutyrate,inhibited olanzapine-induced inflammation and the immune response in the PFC.Conclusion These results suggested olanzapine exposure could be a factor that induces central inflammation and immunological abnormities in schizophrenia subjects.Olanzapine induces PFC inflammation and immune response,possibly via activating ER stress signaling. 展开更多
关键词 OLANZAPINE prefrontal cortex INFLAMMATION immune response endoplasmic reticulum stress
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多螺旋复合箍筋约束混凝土方柱轴压性能有限元分析
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作者 孟和 郭书慧 +1 位作者 鱼涛 杨坤 《西安工业大学学报》 CAS 2024年第5期625-634,共10页
为了研究新型多螺旋复合箍筋约束混凝土方柱的力学性能,本文在其轴压试验的基础上,采用基于试验提出的约束混凝土本构模型,并利用有限元软件ABAQUS进行数值分析,讨论箍筋间距、箍筋强度、箍筋形式及混凝土强度对约束混凝土方柱轴压性能... 为了研究新型多螺旋复合箍筋约束混凝土方柱的力学性能,本文在其轴压试验的基础上,采用基于试验提出的约束混凝土本构模型,并利用有限元软件ABAQUS进行数值分析,讨论箍筋间距、箍筋强度、箍筋形式及混凝土强度对约束混凝土方柱轴压性能的影响。结果表明,数值模拟的多螺旋复合箍筋约束混凝土轴压方柱的应力-应变曲线与试验曲线拟合较好,验证了本文所提本构模型的适用性及所建有限元模型的合理性;多螺旋复合箍筋明显提高了约束混凝土方柱的强度和延性性能,约束效果好于传统井字形复合箍筋,且五螺旋复合箍筋的约束效果要好于四螺旋复合箍筋。 展开更多
关键词 约束混凝土 多螺旋复合箍筋 有限元分析 强度和延性
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填料性质对催化裂化油浆静电分离效率影响冷模试验研究
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作者 李亮亮 孟鹤 +1 位作者 李义鹏 兰琦 《石油石化绿色低碳》 CAS 2024年第1期39-44,共6页
为分析静电分离法脱除催化裂化油浆中固含量影响因素,采用自制静电分离器试验装置,研究填料直径和材质对催化油浆中催化剂固体颗粒脱除效率影响规律。结合数值模拟,分析填料直径和材质对其接触点处电场强度变化的影响。结果表明,油浆中... 为分析静电分离法脱除催化裂化油浆中固含量影响因素,采用自制静电分离器试验装置,研究填料直径和材质对催化油浆中催化剂固体颗粒脱除效率影响规律。结合数值模拟,分析填料直径和材质对其接触点处电场强度变化的影响。结果表明,油浆中固体颗粒分离效率随填料直径增大而降低,氧化锆填料的分离效率最高,玻璃填料的分离效果最差。随填料直径和填料相对介电常数增大,填料接触点处的电场强度增大。在不同材质填料物化参数中,填料相对介电常数对油浆中固体颗粒静电分离影响过程起主要作用。 展开更多
关键词 催化裂化油浆 催化剂固体颗粒 静电分离 填料 电场强度 分离效率 冷模试验
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Synthesis and electromagnetic transport of large-area 2D WTe_(2) thin film
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作者 Yumeng Zhang Zhejia Wang +6 位作者 Jiaheng Feng Shuaiqiang Ming Furong Qu Yang Xia meng he Zhimin Hu Jing Wang 《Journal of Semiconductors》 EI CAS CSCD 2022年第10期50-55,共6页
Tungsten telluride thin films were successfully prepared on monocrystal sapphire substrates by using atomic layer de-position and chemical vapor deposition technology,and the effects of different tellurization tempera... Tungsten telluride thin films were successfully prepared on monocrystal sapphire substrates by using atomic layer de-position and chemical vapor deposition technology,and the effects of different tellurization temperatures on the properties of tungsten telluride films were investigated.The growth rate,crystal structure and composition of the film samples were character-ized and analyzed by using scanning electron microscope,Raman spectroscopy and X-ray photoelectron spectroscopy.The res-ults showed that tungsten telluride thin films with good crystal orientation in(001)were obtained at telluride temperature of 550℃.When the telluride temperature reached 570℃,the tungsten telluride began to decompose and unsaturated mag-netoresistance was found. 展开更多
关键词 atomic layer deposition(ALD) chemical vapor deposition(CVD) telluride temperature WTe_(2)thin film
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