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煤-热共采模式下矿井地热水开采及智能调度技术研究 被引量:1
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作者 李延河 万志军 +5 位作者 于振子 张源 张波 甄正 赵东 师鹏 《中国矿业》 2023年第9期110-118,共9页
为响应我国“碳达峰、碳中和”战略目标,实现能源绿色清洁转型,开发深部矿井地热资源具有重要意义。以平煤十矿为背景,利用热储体积法,评价了矿区地热水开发潜力,结果显示矿区地热水蕴藏热能7.63×10^(17)J,折合标煤26.1 Mt,动态地... 为响应我国“碳达峰、碳中和”战略目标,实现能源绿色清洁转型,开发深部矿井地热资源具有重要意义。以平煤十矿为背景,利用热储体积法,评价了矿区地热水开发潜力,结果显示矿区地热水蕴藏热能7.63×10^(17)J,折合标煤26.1 Mt,动态地热流体可采量折合标煤1.01 Mt/a,具有较高开发潜力。基于此,在煤-热共采理论及框架的基础上,提出了矿井地热水开采方法,并提出了一种基于地面热负荷的地热水开采智能调度技术。通过计算矿区热负荷,设计了矿井地热水开采方案,并进行了现场工业性实验。实验结果表明,开发利用矿井地热水可满足平煤十矿矿区17万m^(2)的冬季供暖及7000余名职工日常洗浴,同时可减少燃煤约10327 t/a,折合CO_(2)排放量2.69×10^(4)t/a,为企业带来693.8万元的经济效益。因此,深部矿井地热水开采具有良好的安全效益、经济效益、社会效益与环境效益,可为我国“双碳”目标的实现贡献力量。 展开更多
关键词 煤-热共采 地热水 热负荷 矿区供暖 井筒防冻 高温矿井
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三代非能动核电厂乏燃料贮运系统衰变热计算及关键因素研究
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作者 王梦琪 彭超 +2 位作者 黎辉 郑征 梅其良 《辐射防护》 CAS CSCD 北大核心 2023年第S01期14-19,共6页
本文以三代非能动核电厂国和一号乏燃料组件为研究对象,基于ANS5.1—2005和ORIGEN-S软件的衰变热计算开展对比研究,分析了不同冷却时间下裂变产物、锕系元素衰变热变化规律。结果显示,对于冷却时间在5年以上的乏燃料,锕系元素占总衰变... 本文以三代非能动核电厂国和一号乏燃料组件为研究对象,基于ANS5.1—2005和ORIGEN-S软件的衰变热计算开展对比研究,分析了不同冷却时间下裂变产物、锕系元素衰变热变化规律。结果显示,对于冷却时间在5年以上的乏燃料,锕系元素占总衰变热的贡献接近20%甚至更高,锕系元素的主要贡献来自于Cm-244、Pu-238和Am-241。ANS 5.1-2005对锕系元素仅考虑了U-239和Np-239,对于冷却时间较长的乏燃料贮运系统,相对ANS 5.1—2005,ORIGEN-S衰变热计算结果更加保守。建议在三代非能动核电厂乏燃料的贮运系统衰变热计算中采用基于ORIGEN-S等类似功能的专用程序进行计算。 展开更多
关键词 衰变热 裂变产物 锕系元素
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可液化地层中盾构施工诱发振动影响的数值模拟研究
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作者 王菁悦 葛忻声 +5 位作者 吴平 甄正 王智强 田茂国 李沛轩 张军 《工程抗震与加固改造》 北大核心 2023年第1期158-167,共10页
以太原市地铁2号线人民南路站~化章街站区间可液化地层盾构施工过程中遇到地表沉降超限问题为例,采用FLAC3D有限差分软件,进行盾构隧道施工过程模拟,在开挖面水平方向模拟盾构施工振动的正弦速度边界,进行动力响应分析,分析孔压比、超... 以太原市地铁2号线人民南路站~化章街站区间可液化地层盾构施工过程中遇到地表沉降超限问题为例,采用FLAC3D有限差分软件,进行盾构隧道施工过程模拟,在开挖面水平方向模拟盾构施工振动的正弦速度边界,进行动力响应分析,分析孔压比、超静孔隙水压力、加速度时程曲线。分析结果表明:盾构机掘进太原市复合地层在隧道上覆黏质粉土及粉细砂层中形成一定液化区域,上覆土层中开挖面前方液化区域面积明显大于开挖面后方液化面积;盾构隧道轴线对应地表沉降最大值达60mm,与现场实测值相同,最大沉降发生在开挖面前方1m处;超静孔隙水压力在液化土层中形成一旋涡区,漩涡中心靠近液化层底部,位于开挖面前方,超静孔隙水压力在漩涡区中心最大,向四周扩散逐渐减小。本文的研究成果对盾构在可液化地层中的施工有一定参考价值。 展开更多
关键词 太原盾构隧道 可液化地层 FLAC^(3D)数值模拟 超孔压比 超静孔隙水压力
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流固耦合作用下盾构下穿高架桥稳定性分析 被引量:8
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作者 甄正 葛忻声 +1 位作者 王菁悦 张军 《科学技术与工程》 北大核心 2021年第22期9605-9614,共10页
依托太原铁路枢纽新建西南环线盾构隧道,结合盾构施工中的监测资料,利用有限元分析软件进行数值模拟分析,在考虑流固耦合作用下,并结合实际监测资料,研究了盾构下穿高架桥时地表和地下结构的稳定性,得出了地表、桥承台和桥桩的变形规律... 依托太原铁路枢纽新建西南环线盾构隧道,结合盾构施工中的监测资料,利用有限元分析软件进行数值模拟分析,在考虑流固耦合作用下,并结合实际监测资料,研究了盾构下穿高架桥时地表和地下结构的稳定性,得出了地表、桥承台和桥桩的变形规律及隧道周围孔隙水压力分布规律。研究结果表明:在富水地层中盾构下穿高架桥工程中,考虑流固耦合作用是必要且合理的;盾构隧道施工前采用隔离桩结合深层地层注浆的加固措施能有效地控制地表、桥承台和桥桩变形;盾构掘进过程中主要影响桥桩水平横向位移,对水平纵向和竖直方向位移影响较小;桥桩顶部受到的附加弯矩较大;深层地层注浆加固措施能减弱隧道周围流固耦合作用,降低隧道内涌水风险。 展开更多
关键词 流固耦合 盾构隧道 下穿高架桥 数值模拟 稳定性分析
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基于混沌关联维与决策树的运动数据分类研究 被引量:1
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作者 郑贞 邹俊颖 《计算机仿真》 北大核心 2022年第10期327-330,424,共5页
运动数据能够为运动的监测与管理提供指导依据,由于采集设备的差异导致运动数据表现出多源、混沌、非规则等特征,现有运动数据分类方法在准确性和效率等方面仍有欠缺,因此提出了基于混沌关联维与决策树的运动数据分类方法。首先构建运... 运动数据能够为运动的监测与管理提供指导依据,由于采集设备的差异导致运动数据表现出多源、混沌、非规则等特征,现有运动数据分类方法在准确性和效率等方面仍有欠缺,因此提出了基于混沌关联维与决策树的运动数据分类方法。首先构建运动数据相空间,利用时间的自相关与互信息来确定最优混沌延时,利用虚假临界点的条件约束确定最优嵌入维度;根据相空间内存在的关联相点对数量,计算得到关联积分,从而完成数据特征提取。然后针对运动数据的高维属性设计多参决策树,根据信息增益与增益率评价确定分裂规则,根据熵期望确定最优分裂点。最后通过轮廓相似性判断数据所属类别,完成运动数据分类。基于WEKA平台的仿真结果,验证所提方法显著提高了运动数据分类的准确性,准确度达到81.47%,灵敏度达到83.92%,降低了错误分类概率,不合度仅为19.46%;另外,决策树规模与叶子数量的降低,以及吞吐量结果均表明方法具有良好的数据处理速度,有效提升了数据分类效率。 展开更多
关键词 运动数据分类 混沌延时 嵌入维度 关联积分 多参决策树
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盾构下穿浅基础建筑的沉降规律分析 被引量:9
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作者 梁超强 葛忻声 +2 位作者 赵娟 甄正 张军 《太原理工大学学报》 CAS 北大核心 2021年第2期256-262,共7页
盾构施工会引起隧道周围土体变形,使地表已有建筑产生沉降和倾斜。针对太原地区汾河漫滩地层盾构下穿浅基础建筑物这一施工工况,比较FLAC3D模拟与现场监测两种方法得到的结果,分析建筑物存在与否以及建筑物刚度对于沉降规律的影响。结... 盾构施工会引起隧道周围土体变形,使地表已有建筑产生沉降和倾斜。针对太原地区汾河漫滩地层盾构下穿浅基础建筑物这一施工工况,比较FLAC3D模拟与现场监测两种方法得到的结果,分析建筑物存在与否以及建筑物刚度对于沉降规律的影响。结果表明:建筑物的存在对形成的横向沉降槽影响较小,但沉降过程与没有建筑物相比差别很大,建筑物的存在会约束周围土体,使建筑物及周围地层在沉降过程中表现出滞后性和整体性;建筑物刚度的改变对沉降滞后性的影响较小,刚度越大整体性越强。研究成果有助于盾构施工过程中建筑物及周围地层变形的预测。 展开更多
关键词 盾构隧道 沉降规律 约束性 滞后性 整体性
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奥拉西坦治疗脑出血后认知障碍的效果及安全性的meta分析 被引量:7
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作者 薛道金 尹莲君 +5 位作者 孟锦园 甄政 詹杰 沈有碧 彭子壮 黄涛 《中国医药导报》 CAS 2021年第29期77-81,共5页
目的系统评价奥拉西坦治疗脑出血后认知障碍的效果及安全性。方法计算机检索CNKI、Wanfang Data、VIP、CBM、Embase、PubMed、the Cochrane Library数据库中有关奥拉西坦治疗脑出血后认知障碍的随机对照试验,检索时限从建库至2020年11... 目的系统评价奥拉西坦治疗脑出血后认知障碍的效果及安全性。方法计算机检索CNKI、Wanfang Data、VIP、CBM、Embase、PubMed、the Cochrane Library数据库中有关奥拉西坦治疗脑出血后认知障碍的随机对照试验,检索时限从建库至2020年11月。采用RevMan 5.3软件进行meta分析。结果纳入8篇文献共计616例患者,试验组310例,对照组306例。meta分析结果显示:试验组简易精神状态检查(MMSE)评分(MD=8.85,95%CI:4.82~12.87,P<0.0001)、Barthel指数(MD=17.21,95%CI:15.29~19.14,P<0.0001)均高于对照组。进一步进行亚组分析显示:静滴组MMSE评分(MD=12.33,95%CI:8.54~16.11,P<0.00001)、Barthel指数(MD=20.44,95%CI:17.77~23.11,P<0.00001)和口服组MMSE评分(MD=4.19,95%CI:2.20~6.18,P<0.0001)、Barthel指数(MD=13.73,95%CI:10.95~16.50,P<0.00001)均高于对照组。试验组长谷川痴呆量表评分高于对照组(MD=3.84,95%CI:1.65~6.03,P=0.0006),美国国立卫生研究院卒中量表评分低于对照组(MD=-4.31,95%CI:-6.37~-2.25,P<0.0001)。两组不良反应发生率比较,差异无统计学意义(RR=1.18,95%CI:0.62~2.22,P=0.62)。结论奥拉西坦在改善脑出血患者认知功能、日常生活活动能力、神经功能缺损症状方面具有显著疗效。 展开更多
关键词 奥拉西坦 脑出血 认知障碍 META分析 随机对照试验
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基于波前编码的大焦深弹载双色红外探测系统 被引量:4
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作者 周军 陈守谦 +2 位作者 甄政 欧文 熊健 《红外与激光工程》 EI CSCD 北大核心 2020年第4期75-79,共5页
波前编码技术通过在光学系统光瞳位置加入特殊的相位掩模板,对目标信号光波进行编码调制,并在图像处理端对该编码信号进行解码而恢复原图像,由于被编码调制后的波前对离焦等像差的不敏感度扩大了十数倍,能显著扩大光学系统焦深。因此,... 波前编码技术通过在光学系统光瞳位置加入特殊的相位掩模板,对目标信号光波进行编码调制,并在图像处理端对该编码信号进行解码而恢复原图像,由于被编码调制后的波前对离焦等像差的不敏感度扩大了十数倍,能显著扩大光学系统焦深。因此,波前编码技术能在编码与解码之间解决恶劣力热条件或多色制导体制对弹载红外探测系统带来的离焦和对准误差。文中基于波前编码扩大焦深基本原理,对一长长双色红外光学系统进行了10倍焦深扩大的波前编码像差钝化设计。集成样机后,进行了波前编码成像实验。以小孔点靶编码像作为PSF解码10倍离焦位置处的十字靶和四条靶图像,十字靶和四条靶解码图像清晰可辨,证明波前编码技术对于系统像差或离焦像差的抑制是有效的。最后,对波前编码成像效果进行了分析:解码图像的水波纹是由于空间采样PSF不足导致的,可提取不同视场位置PSF,使用空间变化解码算法实现条纹消除;由于解码图像会在放大信号的同时放大噪声,因此,解码算法需要进一步研究噪声抑制算法,以期满足弹载高能量、高信噪比应用的要求。 展开更多
关键词 波前编码 焦深 红外探测 像差钝化
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长节段椎管内尤文肉瘤1例报告并文献回顾
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作者 郭韩玉 黄涛 +2 位作者 甄政 张志强 李聪 《安徽医药》 CAS 2022年第11期2291-2295,共5页
目的提高临床医师对椎管内尤文肉瘤(Ewing sarcoma,EWS)的认识,减少误诊,争取早期诊断,早期治疗,改善病人的预后。方法对广州中医药大学第二临床医学院神经外科2020年4月收治的1例长节段椎管内EWS病人的临床资料进行整理并回顾相关文献... 目的提高临床医师对椎管内尤文肉瘤(Ewing sarcoma,EWS)的认识,减少误诊,争取早期诊断,早期治疗,改善病人的预后。方法对广州中医药大学第二临床医学院神经外科2020年4月收治的1例长节段椎管内EWS病人的临床资料进行整理并回顾相关文献。结果病人主诉为进行性四肢麻木乏力1月余。术前初步诊断:脊髓占位性病变(C1-T1椎体,血管源性肿瘤?脊膜瘤?神经元性肿瘤?)。入院后9 d行C1-T1椎体占位性病变切除术,术后病理提示:小圆细胞恶性肿瘤;免疫组化:CD99(+)、S-100(+)。结合免疫组化及分子病理结果:符合椎管内EWS。出院在外院行7个疗程CAV/IE化疗,随访1年,病人复发于外院行手术及放化疗。结论椎管内EWS的来源为原始神经上皮,其构成为原始未分化小圆细胞,是一类发生率极低的高度恶性肿瘤,其预后不佳、病程短、容易误诊、进展快。目前确诊主要依赖于病理学和免疫组化。 展开更多
关键词 肉瘤 EWING 椎管内肿物 原始神经外胚层肿瘤 长节段 文献回顾
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High-efficiency extraction synthesis for high-purity copper nanowires and their applications in flexible transparent electrodes 被引量:4
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作者 He Zhang Shang Wang +6 位作者 Yanhong Tian Jiayue Wen Chunjin Hang zhen zheng Yilong Huang Su Ding Chenxi Wang 《Nano Materials Science》 CAS 2020年第2期164-171,共8页
Copper nanowires(Cu NWs)are considered an excellent alternative to indium tin oxide(ITO)in flexible transparency electrodes(FTEs).However,the mixed particles and surface oxidation of Cu NWs degrade the transmittance a... Copper nanowires(Cu NWs)are considered an excellent alternative to indium tin oxide(ITO)in flexible transparency electrodes(FTEs).However,the mixed particles and surface oxidation of Cu NWs degrade the transmittance and conductivity of the electrodes.Therefore,highly purified Cu NWs without oxidation are vital for high-performance FTEs.Herein,a facile and effective purification process is introduced to purify Cu NWs in a water and n-hexane system,which takes advantage of the differences in hydrophilicity between Cu NWs and Cu NPs caused by their different adsorption affinities to octadecylamine(ODA).At the same sheet resistance,the transmittance of the purified Cu NW-based FTEs improved approximately 2%compared to that of non-purified Cu NW-based FTEs.Immersion of the electrode in glacial acetic acid removed the surface organics and oxides.After only 40 s of treatment,the sheet resistance dramatically decreased from 10^5 Ohm/sq to 31 Ohm/sq with a transmittance of 85%.In addition,the Cu NW-based FTE conductors showed excellent flexibility(remaining stable after 1000 bending cycles).The Cu NW-based FTEs were further applied to fabricate a flexible transparent heater.At a voltage of 10 V,the temperature of the heater reached 73℃,demonstrating the potential applications of this material in various fields. 展开更多
关键词 Copper nanowires PURIFICATION Transparent electrode Flexible electronics
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一种新型红外多波段低背景探测技术 被引量:2
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作者 甄政 王英瑞 +2 位作者 欧文 周军 李昂 《红外与激光工程》 EI CSCD 北大核心 2020年第5期145-149,共5页
红外低背景探测技术主要应用在深空环境,系统灵敏度与自身背景辐射关系较大,如何有效抑制探测系统自身背景辐射一直是重点研究方向;识别一直是红外领域的研究热点,增加探测谱段是提高特征获取量的最有效方式。介绍了一种局部制冷分光的... 红外低背景探测技术主要应用在深空环境,系统灵敏度与自身背景辐射关系较大,如何有效抑制探测系统自身背景辐射一直是重点研究方向;识别一直是红外领域的研究热点,增加探测谱段是提高特征获取量的最有效方式。介绍了一种局部制冷分光的红外多波段探测技术,该技术采用探测器一体化设计思路,将折反结构光学系统局部集成到探测器内部随红外芯片一起制冷;再利用分光元件进行双路分光,实现双波段能力,如果结合叠层芯片可以有效拓展到多波段能力;通过光学自辐射仿真,比较不同光学结构形式下的自辐射结果,可以看出:该技术背景辐射降低至常温折反系统背景辐射1/4,理论灵敏度可以大幅度提高,该技术优势明显,潜力巨大。 展开更多
关键词 低背景探测 灵敏度 背景辐射 红外多波段 制冷
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Tourmaline geochemistry and boron isotopic variations as a guide to fluid evolution in the Qiman Tagh W-Sn belt, East Kunlun, China 被引量:1
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作者 zhen zheng Yanjing Chen +3 位作者 Xiaohua Deng Suwei Yue Hongjin Chen Qingfei Wang 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第2期569-580,共12页
The Qiman Tagh W-Sn belt lies in the westernmost section of the East Kunlun Orogen, NW China, and is associated with early Paleozoic monzogranites, tourmaline is present throughout this belt. In this paper we report c... The Qiman Tagh W-Sn belt lies in the westernmost section of the East Kunlun Orogen, NW China, and is associated with early Paleozoic monzogranites, tourmaline is present throughout this belt. In this paper we report chemical and boron isotopic compositions of tourmaline from wall rocks, monzogranites, and quartz veins within the belt, for studying the evolution of ore-forming fluids. Tourmaline crystals hosted in the monzogranite and wall rocks belong to the alkali group, while those hosted in quartz veins belong to both the alkali and X-site vacancy groups. Tourmaline in the walk rocks lies within the schorl-dravite series and becomes increasingly schorlitic in the monzogranite and quartz veins. Detrital tourmaline in the wall rocks is commonly both optically and chemically zoned,with cores being enriched in Mg compared with the rims. In the Al-Fe-Mg and Ca-Fe-Mg diagrams,tourmaline from the wall rocks plots in the fields of Al-saturated and Ca-poor metapelite, and extends into the field of Li-poor granites, while those from the monzogranite and quartz veins lie within the field of Li-poor granites. Compositional substitution is best represented by the MgFe_(-1), Al(NaR)_(-1), and AlO(Fe(OH))_(-1) exchange vectors. A wider range of δ^(11)B values from -11.1‰ to -7.1‰ is observed in the wall-rock tourmaline crystals, the B isotopic values combining with elemental diagrams indicate a source of metasediments without marine evaporates for the wall rocks in the Qiman Tagh belt. The δ^(11)B values of monzogranite-hosted tourmaline range from -10.7‰ and-9.2‰, corresponding to the continental crust sediments, and indicate a possible connection between the wall rocks and the monzogranite. The overlap in δ^(11)B values between wall rocks and monzogranite implies that a transfer of δ^(11)B values by anataxis with little isotopic fractionation between tourmaline and melts. Tourmaline crystals from quartz veins have δ^(11)B values between -11.0‰ and-9.6‰, combining with the elemental diagrams and geological features, thus indicating a common granite-derived source for the quartz veins and little B isotopic fractionation occurred. Tourmalinite in the wall rocks was formed by metasomatism by a granite-derived hydrothermal fluid, as confirmed by the compositional and geological features.Therefore, we propose a single B-rich sedimentary source in the Qiman Tagh belt, and little boron isotopic fractionation occurred during systematic fluid evolution from the wall rocks, through monzogranite, to quartz veins and tourmalinite. 展开更多
关键词 TOURMALINE Chemical composition BORON isotope Qiman Tagh W-Sn BELT Fluid evolution
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Effects of fast ions produced by ICRF heating on the pressure at EAST
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作者 郑振 项农 +1 位作者 杨程 徐颖峰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第2期38-46,共9页
Ion cyclotron resonance heating(ICRH),which can produce fast ions,is an important auxiliary heating method at EAST.To analyze the effect of ICRH-induced fast ions on the plasma pressure at EAST,simulations are perform... Ion cyclotron resonance heating(ICRH),which can produce fast ions,is an important auxiliary heating method at EAST.To analyze the effect of ICRH-induced fast ions on the plasma pressure at EAST,simulations are performed using TRANSP and TORIC codes.It is found that the ICRF-induced fast ion pressure cannot be negligible when the ICRF power is sufficiently high.The magnitude of the total ion pressure can be raised up to 60%of the total pressure as the input power rises above 3 MW.The pressure profile is also significantly modified when the resonant layer is changed.It is shown that by changing the wave frequency and antenna position,the total ion pressure profile can be broadened,which might provide an option for profile control at EAST. 展开更多
关键词 ICRH EQUILIBRIUM fast ion pressure minority heating
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Kinetic equilibrium reconstruction for the NBI-and ICRH-heated H-mode plasma on EAST tokamak
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作者 郑振 项农 +8 位作者 陈佳乐 丁斯晔 杜红飞 李国强 王一丰 刘海庆 李颖颖 吕波 臧庆 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第6期30-38,共9页
The equilibrium reconstruction is important to study the tokamak plasma physical processes.To analyze the contribution of fast ions to the equilibrium,the kinetic equilibria at two time-slices in a typical H-mode disc... The equilibrium reconstruction is important to study the tokamak plasma physical processes.To analyze the contribution of fast ions to the equilibrium,the kinetic equilibria at two time-slices in a typical H-mode discharge with different auxiliary heatings are reconstructed by using magnetic diagnostics,kinetic diagnostics and TRANSP code.It is found that the fast-ion pressure might be up to one-third of the plasma pressure and the contribution is mainly in the core plasma due to the neutral beam injection power is primarily deposited in the core region.The fast-ion current contributes mainly in the core region while contributes little to the pedestal current.A steep pressure gradient in the pedestal is observed which gives rise to a strong edge current.It is proved that the fast ion effects cannot be ignored and should be considered in the future study of EAST. 展开更多
关键词 kinetic equilibrium reconstruction NBI ICRH pressure gradient edge current fast ions
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The Anneal Temperature Effect on the BTO and NZFO Films and Their Capacitance-Inductance Integrated Device
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作者 zhen zheng Yuhao Shi +1 位作者 Chengjie Shi Chunqing Wang 《Semiconductor Science and Information Devices》 2019年第1期2-7,共6页
In this paper,a novel capacitor-inductor integrated structure was proposed.The dielectric material BaTiO3(BTO)and ferromagnetic material Ni0.5Zn0.5Fe2O4(NZFO)was prepared by sol-gel method.Phase composition and morpho... In this paper,a novel capacitor-inductor integrated structure was proposed.The dielectric material BaTiO3(BTO)and ferromagnetic material Ni0.5Zn0.5Fe2O4(NZFO)was prepared by sol-gel method.Phase composition and morphology of the thin films were characterized by XRD,SEM and AFM.The effect of annealing temperature on film crystallinity,surface morphology,dielectric properties and ferromagnetism was investigated.When the annealing temperature was 700°C,the BTO film and the NZFO film got the better dielectric properties and ferromagnetic properties.Then the BTO thin film was spin-coated on the substrate,and the NZFO thin film was in-situ sintered on the BTO thin film.The composite film possessed both ferromagnetism and dielectric properties.Finally,an inductive coil was fabricated on the BTO/NZFO composite film to produce a capacitance and inductance integrated device. 展开更多
关键词 Capacitor-inductor Integrated device BTO FILM NZFO FILM ANNEAL temperature
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Discovery of a potent and highly selective inhibitor of SIRT6 against pancreatic cancer metastasis in vivo
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作者 Xinyuan Xu Qian Zhang +14 位作者 Xufeng Wang Jing Jin Chengwei Wu Li Feng Xiuyan Yang Mingzhu Zhao Yingyi Chen Shaoyong Lu zhen zheng Xiaobing Lan Yi Wang Yan zheng Xuefeng Lu Qiufen Zhang Jian Zhang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2024年第3期1302-1316,共15页
Pancreatic cancer,one of the most aggressive malignancies,has no effective treatment due to the lack of targets and drugs related to tumour metastasis.SIRT6 can promote the migration of pancreatic cancer and could be ... Pancreatic cancer,one of the most aggressive malignancies,has no effective treatment due to the lack of targets and drugs related to tumour metastasis.SIRT6 can promote the migration of pancreatic cancer and could be a potential target for antimetastasis of pancreatic cancer.However,highly selective and potency SIRT6 inhibitor that can be used in vivo is yet to be discovered.Here,we developed a noveSIRT6 allosteric inhibitor,compound 11e,with maximal inhibitory potency and an IC_(50) value of 0.98±0.13μmol/L.Moreover,compound 11e exhibited significant selectivity against other histone deacetylases(HADC1-11 and SIRT1-3)at concentrations up to 100μmol/L.The allosteric site and the molecular mechanism of inhibition were extensively elucidated by cocrystal complex structure and dynamic structural analyses.Importantly,we confirmed the antimetastatic function of such inhibitors in four pancreatic cancer cell lines as well as in two mouse models of pancreatic cancer liver metastasis.To our knowledge,this is the first study to reveal the in vivo effects of SIRT6 inhibitors on liver metastatic pancreatic cancer.It not only provides a promising lead compound for subsequent inhibitor developmentargeting SIRT6 but also provides a potential approach to address the challenge of metastasis in pancreatic cancer. 展开更多
关键词 SIRT6 INHIBITOR ALLOSTERIC SELECTIVITY COCRYSTAL Pancreatic cancer metastasis
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Underwater four-quadrant dual-beam circumferential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-LMS algorithm
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作者 Guangbo Xu Bingting Zha +2 位作者 Hailu Yuan zhen zheng He Zhang 《Defence Technology(防务技术)》 SCIE EI CAS 2024年第7期1-13,共13页
The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser fuzes.To overcome this issue,we propose a four-quadrant ... The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser fuzes.To overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering algorithm.This enhances the algorithm loading capability of the fuze.In order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)algorithm.We also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the fuze.Finally,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo signals.The experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance. 展开更多
关键词 Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm
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Pulmonary fibrosis:A short-or long-term sequelae of severe COVID-19?
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作者 zhen zheng Fei Peng Yong Zhou 《Chinese Medical Journal Pulmonary and Critical Care Medicine》 2023年第2期77-83,共7页
The pandemic of coronavirus disease 2019(COVID-19),caused by a novel severe acute respiratory syndrome(SARS)coronavirus 2(SARS-CoV-2),has caused an enormous impact on the global healthcare.SARS-CoV-2 infec-tion primar... The pandemic of coronavirus disease 2019(COVID-19),caused by a novel severe acute respiratory syndrome(SARS)coronavirus 2(SARS-CoV-2),has caused an enormous impact on the global healthcare.SARS-CoV-2 infec-tion primarily targets the respiratory system.Although most individuals testing positive for SARS-CoV-2 present mild or no upper respiratory tract symptoms,patients with severe COVID-19 can rapidly progress to acute respira-tory distress syndrome(ARDS).ARDS-related pulmonary fibrosis is a recognized sequelae of COVID-19.Whether post-COVID-19 lung fibrosis is resolvable,persistent,or even becomes progressive as seen in human idiopathic pulmonary fibrosis(IPF)is currently not known and remains a matter of debate.With the emergence of effective vaccines and treatments against COVID-19,it is now important to build our understanding of the long-term se-quela of SARS-CoV-2 infection,to identify COVID-19 survivors who are at risk of developing chronic pulmonary fibrosis,and to develop effective anti-fibrotic therapies.The current review aims to summarize the pathogenesis of COVID-19 in the respiratory system and highlights ARDS-related lung fibrosis in severe COVID-19 and the potential mechanisms.It envisions the long-term fibrotic lung complication in COVID-19 survivors,in particular in the aged population.The early identification of patients at risk of developing chronic lung fibrosis and the development of anti-fibrotic therapies are discussed. 展开更多
关键词 Coronavirus disease 2019(COVID-19) Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) Lung fibrosis
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内外套管组合沉管夯扩法在大厚度湿陷性黄土地基中的现场试验研究 被引量:8
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作者 王鼎 葛忻声 +2 位作者 甄正 李斌 刘清洁 《建筑结构》 CSCD 北大核心 2019年第6期134-137,共4页
由传统技术改进而来的内外套管组合沉管夯扩法,是一种利用内外套管组合沉管成孔,加大成孔深度,再由重锤二次夯扩挤密的新技术,地基处理深度可达60m。结合具体的工程,对在大厚度湿陷性黄土地基中使用该方法成桩的桩长26,32,35m的灰土挤... 由传统技术改进而来的内外套管组合沉管夯扩法,是一种利用内外套管组合沉管成孔,加大成孔深度,再由重锤二次夯扩挤密的新技术,地基处理深度可达60m。结合具体的工程,对在大厚度湿陷性黄土地基中使用该方法成桩的桩长26,32,35m的灰土挤密桩和桩长20,32,36m的水泥土挤密桩进行现场试验研究,测得两种桩间土挤密系数均不小于0.93,桩体压实系数均不小于0.97,湿陷系数均小于0.015,满足规范要求;同时承载力也满足设计要求。 展开更多
关键词 大厚度湿陷性黄土 内外套管组合沉管夯扩法 地基处理
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基于流固耦合作用的太原砂卵石层盾构隧道变形特性分析 被引量:5
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作者 甄正 葛忻声 张军 《公路》 北大核心 2021年第4期361-367,共7页
依托太原铁路枢纽新建西南环线勘察资料,结合盾构施工中实际的监测资料,利用Plaxis软件模拟分析了考虑与不考虑流固耦合作用下盾构机在砂卵石层中的掘进情况,研究了盾构施工扰动引起的地表沉降、隧道周围主应力和孔隙水压力变化的规律... 依托太原铁路枢纽新建西南环线勘察资料,结合盾构施工中实际的监测资料,利用Plaxis软件模拟分析了考虑与不考虑流固耦合作用下盾构机在砂卵石层中的掘进情况,研究了盾构施工扰动引起的地表沉降、隧道周围主应力和孔隙水压力变化的规律。研究结果表明:考虑耦合作用下的地表沉降范围比不考虑耦合作用广,与实际情况接近,砂卵石地区的沉降槽系数约为15m;考虑耦合与不耦合作用下拱顶和拱底都出现斑点状的低应力集中区域,而考虑耦合作用下的拱顶处最大主应力场呈现漏斗状,耦合主要影响最大主应力分布;考虑耦合作用下拱腰的孔隙水压力呈"勺子"状,并在隧道周围产生了负值的超孔隙水压力,孔隙水压力主要在拱腰和拱底处变化。 展开更多
关键词 盾构隧道 流固耦合 地表沉降 主应力 孔隙水压力
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