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Mass Increase with Strong and Gravitational Potentials, and Mass Defect with Electromagnetic Potential
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作者 Hany Ali Hussein 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1079-1094,共16页
The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons,... The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons, & mesons) and their components (quarks), mass difference between nucleus and its individual components (protons and neutrons), massless of gamma photons, abnormal masses of mesons and bosons, and the excess in galaxy masses (dark matter). Also, this proposal shows the exact relation between mass and energy: Strong Potential=−3.04mc2| Electric Potential |=−5.57×10−3mc2Gravitational Potential=−1.22×10−7mc2where m represents the excess in mass due to strong potential, or gravitational potential and represents the decrease in mass due to electromagnetic potential. Released energy here equals potential energy and doesn’t equal decrease in mass using the formula E = mc2. Released energy is transferred to heat, photons, kinetic energy… Finally, proposal will try to describe the relation between photon energy and mass of its components using the general equation of kinetic energy: Photon Energy=1/2mc2m is the sum of the individual masses of its components, while the total mass of photon is zero. 展开更多
关键词 mass defect Dark Matter PHOTON Gamma Photon Strong Potential Gravitational Potential Electromagnetic Potential QUARKS Mesons BOSONS Deuterium Proton Neutron
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Using of the Generalized Special Relativity (GSR) in estimating the proton (nucleon) mass to explain the mass defect 被引量:4
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作者 Mahmoud Hamid Mahmoud Hilo M. D. Abd Allah Khalid Mohammed Haroon 《Natural Science》 2011年第2期141-144,共4页
This paper presents theoretical investigation on explanation of the mass defect estimating a new value for the proton mass inside the nucleus in the presence of the gravitational potential, the work has been done by u... This paper presents theoretical investigation on explanation of the mass defect estimating a new value for the proton mass inside the nucleus in the presence of the gravitational potential, the work has been done by using a new theory called the generalized special relativity (GSR). 展开更多
关键词 Generalized mass defect GSR APPROXIMATIONS
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Characterization of metabolic profiles of Lanqin Oral Liquid in rats by ultra-high-performance liquid chromatography tandem time-of-flight mass spectrometry
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作者 Yue-Yue Tan Meng-Yuan Wang +6 位作者 Yu-Nuo Fan Ya-Liu Fan Ye Zhang Bin Li Yong-Xiang Wang Hua Yang Ping Li 《Acupuncture and Herbal Medicine》 2025年第1期76-88,共13页
Objective:Lanqin oral liquid(LOL),as a traditional Chinese medicine prescription,has obvious clinical efficacy in the treatment of pharyngeal inflammation.Exploring the distribution of LOL prototype components and met... Objective:Lanqin oral liquid(LOL),as a traditional Chinese medicine prescription,has obvious clinical efficacy in the treatment of pharyngeal inflammation.Exploring the distribution of LOL prototype components and metabolites in plasma is of great significance for understanding potentially effective compounds.The aim of this study is to elucidate the metabolites and main metabolic pathways of LQL in vivo.Methods:In this study,a reliable approach integrated background subtraction and mass defect filtering(MDF),based on quadrupole time-of-flight mass spectrometry(QTOF-MS)technology,was performed to systematically scan the metabolites of LOL in rat plasma.In addition,according to the prototype mass spectrometry fragmentation pattern and combined with metabolic pathway analysis,a biotransformation oriented analysis strategy was established and applied to the identification of metabolites in LOL in vivo.Results:As a result,159 compounds(58 prototypes and 101 metabolites)were identified or tentatively characterized in drug-containing plasma,including 74 flavonoids,30 alkaloids,34 terpenoids,five phenylpropanoids,six phenolic acids,five fatty acids,and five other type components.The main metabolic pathways include methylation,demethylation,hydroxylation,hydrogenation,glucuronidation,and sulfation.Conclusions:This study provides an overall characterization of the metabolites of LOL in vivo for the first time,providing a solid material basis for exploring the therapeutic effects and pharmacological mechanisms of LOL. 展开更多
关键词 Background subtracts Lanqin Oral Liquid mass defect filtering Metabolic profiles UHPLC-QTOF-MS
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Direct Derivation of the Neutrino Mass
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作者 Volodymyr Krasnoholovets 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期621-646,共26页
In this paper, the submicroscopic deterministic concept developed by the author is applied to the problem of the neutrino mass. A particle appears from space considered as a mathematical lattice of primary topological... In this paper, the submicroscopic deterministic concept developed by the author is applied to the problem of the neutrino mass. A particle appears from space considered as a mathematical lattice of primary topological balls, and induces a deformation coat in its surrounding. The principles of the interaction of particles with space and through space between themselves are considered in detail. The approach states that real quarks possess only an integer charge (±e) and when moving they periodically change to the monopole state (&rlarr;g) and hence, canonical particles are dynamic dyons. A neutrino emerges as a squeezed quark when it is in a monopole state, or in other words, the quark monopole state (a bubble in the tessellattice) is transferred to the appropriate lepton monopole state (a speck in the tessellattice). The self-mass (a “rest” mass) for each neutrino flavour is calculated. The calculated value of the self-mass for the electron anti-neutrino is 1.22873978 × 10<sup>-36</sup> kg = 0.68927247 eV/c<sup>2</sup>. The concept of neutrino oscillations is revised, and another postulation is proposed, namely, that the transition from lighter to heavier flavors is due to the inelastic scattering of neutrinos on oncoming scatterers. As a result, the neutrino captures the mass defect, becomes heavier, and therefore the transitions V<sub>e</sub>&xrarr;V<sub>μ</sub> and V<sub>μ</sub>&xrarr;V<sub>τ</sub> occur;thus, the number of light neutrinos decreases in the neutrino flux studied. 展开更多
关键词 CHARGE Inerton mass defect MONOPOLE NEUTRINO Space Tessellattice
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榫卯连接缝合术在胸背部浅表肿物切除术中的应用研究
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作者 游小恩 江渊 《中国烧伤创疡杂志》 2025年第4期288-291,共4页
目的分析榫卯连接缝合术在胸背部浅表肿物切除术中的应用效果。方法选取2021年3月至2023年3月丽水市人民医院收治的36例拟行胸背部浅表肿物切除的患者作为研究对象,按照术中不同缝合方法将其分为榫卯连接缝合组(20例)和传统减张缝合组(1... 目的分析榫卯连接缝合术在胸背部浅表肿物切除术中的应用效果。方法选取2021年3月至2023年3月丽水市人民医院收治的36例拟行胸背部浅表肿物切除的患者作为研究对象,按照术中不同缝合方法将其分为榫卯连接缝合组(20例)和传统减张缝合组(16例),榫卯连接缝合组患者肿物切除术中切口采用榫卯连接缝合术一期线性缝合,传统减张缝合组患者肿物切除术中切口采用皮肤减张缝合术一期缝合,对比两组患者切口愈合时间、医疗费用、切口缝合难度评分、愈后皮肤瘢痕增生情况以及不良事件发生情况。结果榫卯连接缝合组患者切口愈合时间、医疗费用与传统减张缝合组无明显差异(t/Z=0.021、-1.216,P=0.984、0.236),而切口缝合难度评分明显高于传统减张缝合组(Z=-4.227,P<0.001);术后3个月,榫卯连接缝合组患者愈后皮肤温哥华瘢痕量表(VSS)中的色泽、血管分布、厚度、柔软度评分均明显低于传统减张缝合组(t/Z=2.889、4.764、-4.881、-4.848,P=0.007、P<0.001、P<0.001、P<0.001);术后,榫卯连接缝合组患者不良事件发生率与传统减张缝合组无明显差异(χ^(2)=0.360,P=0.549)。结论与传统皮肤减张缝合相比,胸背部浅表肿物切除术中应用榫卯连接缝合术一期线性缝合切口虽难度较大,但却能降低愈后皮肤瘢痕增生程度,且不会增加切口愈合时间、医疗费用及术后不良事件发生风险。 展开更多
关键词 榫卯连接缝合术 美容缝合 胸背 浅表肿物 皮肤缺损 手术切口 瘢痕
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基于UHPLC-Q Exactive-Orbitrap MS技术的大鼠体内胆汁酸成分分析
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作者 张嘉静 林玟秀 +3 位作者 白俊其 庞淞元 黄娟 丘小惠 《药物分析杂志》 北大核心 2025年第4期605-633,共29页
目的:采用UHPLC-Q Exactive Orbitrap MS技术鉴定SD大鼠体内胆汁酸类成分,并利用本研究建立的胆汁酸数据库研究胆汁酸循环过程中各组织胆汁酸分布情况。方法:以0.1%甲酸水-乙腈作为流动相梯度洗脱,流速为0.2 mL·min^(-1),在电喷雾... 目的:采用UHPLC-Q Exactive Orbitrap MS技术鉴定SD大鼠体内胆汁酸类成分,并利用本研究建立的胆汁酸数据库研究胆汁酸循环过程中各组织胆汁酸分布情况。方法:以0.1%甲酸水-乙腈作为流动相梯度洗脱,流速为0.2 mL·min^(-1),在电喷雾离子源负离子模式下采集大鼠血清、肝脏、胆汁、肠组织、肠内容物、尿液及粪便等生物样品的质谱数据,联合质量亏损过滤、关键离子过滤、提取离子色谱等技术对胆汁酸类成分进行系统筛选,分析体内各组织部位胆汁酸成分。结果:本研究鉴定了449个胆汁酸成分,包括139个游离型胆汁酸,112个牛磺酸结合型胆汁酸,44个甘氨酸结合型胆汁酸,56个硫酸化胆汁酸,36个葡萄糖醛酸化胆汁酸,3个N-乙酰氨基葡萄糖结合型胆汁酸,7个六碳糖结合型胆汁酸,19个非C24的胆汁酸,2个乙酰化胆汁酸,其他氨基酸结合型胆汁酸15个,并新发现与有机酸小分子结合胆汁酸12个。肝脏、胆汁、十二指肠、空肠组织及其肠内容物牛磺酸结合型胆汁酸含量最多,回肠内容物中游离型胆汁酸与牛磺酸结合型胆汁酸含量接近,血清及结肠内容物、尿液、粪便中游离型胆汁酸含量最高。结论:本研究可为进一步探索体内胆汁酸代谢在胆汁酸异常相关疾病中的作用奠定基础数据。 展开更多
关键词 胆汁酸 超高效液相色谱-高分辨四极杆静电场轨道阱联用质谱 鉴定 体内分布 代谢产物 肠肝循环 质量亏损过滤
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基于UPLC-Q-Orbitrap-MS的整合定性策略分析茯苓类药材差异化学成分
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作者 王佳媛 范晓涵 +7 位作者 魏晓晓 曹蓉 王进 王蕾 许凤清 黄顺旺 吴德玲 赵宏苏 《中国实验方剂学杂志》 北大核心 2025年第7期148-156,共9页
目的:基于超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(UPLC-Q-Orbitrap-MS),联合质量亏损过滤(MDF)和分子网络整合技术,建立快速鉴定茯苓类药材中差异化学成分的分析方法。方法:采用UPLC-Q-Orbitrap-MS对茯苓类药材进行质谱数据... 目的:基于超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(UPLC-Q-Orbitrap-MS),联合质量亏损过滤(MDF)和分子网络整合技术,建立快速鉴定茯苓类药材中差异化学成分的分析方法。方法:采用UPLC-Q-Orbitrap-MS对茯苓类药材进行质谱数据采集及鉴定,借助MDF对三萜类成分进行裂解行为研究和结构鉴定,基于各成分MS/MS离子碎片的相似度创建全球天然产物社会分子网络(GNPS),利用软件Cytoscape 3.6.1可视化结构相似的分子簇,对主要的化合物类别的结构进行鉴定及确证。采用主成分分析(PCA)和正交偏最小二乘法-判别分析(OPLS-DA)等多元统计分析,以变量重要性投影(VIP)值>1、P<0.05为标准筛选5种茯苓类药材的差异成分。结果:通过数据库比对鉴定出66种化合物,经MDF新鉴定出8种化合物,经GNPS新鉴定出28种化合物,共鉴定出102种化学成分,其中三萜类成分43种,糖类成分16种,氨基酸及肽类26种,核苷类3种,其他类化合物14种。茯苓皮和野生茯神中的三萜类成分居多,茯苓和人工茯神的氨基酸及肽类成分最多,茯苓皮的糖类成分最多,茯苓和人工茯神中Ⅰ型三萜和Ⅱ型三萜含量较高,茯苓皮中Ⅲ型三萜含量较高,茯神木中4种类型的三萜类均含量较高,野生茯神中Ⅰ型、Ⅱ型、Ⅳ型三萜含量较高。筛选出12种共有差异化学成分,包括丝氨酸、鸟嘌呤核苷、没食子酸、2-辛烯醛、麦芽三糖、栓菌酸、去氢齿孔酸、松苓新酸、茯苓酸A、茯苓酸B、茯苓酸E、茯苓酸G,在不同茯苓类药材中的相对含量存在明显差异。结论:在5种茯苓类药材中,成分的种类整体相似,但其相对含量存在显著差异,尤其是在三萜类成分的分布上。UPLC-Q-Orbitrap-MS、MDF与GNPS整合技术的联用,可为其他中药的快速定性分析提供思路。 展开更多
关键词 分子网络 质量亏损过滤 超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(UPLC-Q-Orbitrap-MS) 多元统计分析 差异化合物 成分鉴定 三萜类成分
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颌面部软组织缺损术后瘢痕的防治
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作者 马金凤 迪丽达尔·塔西甫拉提 +1 位作者 岳丽 王玲 《中国医疗美容》 2025年第1期123-126,共4页
颌面部肿物的切除以及颌面部外伤等都会造成软组织的缺损,但是皮肤受损后的一大问题是术后瘢痕,而面部是人体重要的解剖部位,其外观的正常与否直接影响人们的社交活动。本文通过回顾瘢痕形成的机制及影响因素,总结了目前在不同阶段减轻... 颌面部肿物的切除以及颌面部外伤等都会造成软组织的缺损,但是皮肤受损后的一大问题是术后瘢痕,而面部是人体重要的解剖部位,其外观的正常与否直接影响人们的社交活动。本文通过回顾瘢痕形成的机制及影响因素,总结了目前在不同阶段减轻瘢痕的临床常用方式。单一的方式往往不能取得显著的效果,综合性的个性化序列治疗或可从多个维度最大限度地减轻瘢痕的形成。 展开更多
关键词 面部肿物 浓缩生长因子 软组织缺损 瘢痕
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基于氦质谱检漏技术的SiC衬底微管检测设备
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作者 周立平 刘慧强 +2 位作者 王琪 李明 张继光 《半导体技术》 北大核心 2025年第9期972-980,共9页
为解决SiC衬底微管缺陷检测精度低、效率差的问题,研制了基于氦质谱检漏技术的SiC衬底微管检测设备。该设备以PFEIFFER公司的ASM 340型检漏仪作为检测核心、西门子S7-1200系列可编程逻辑控制器(PLC)作为控制核心、节卡机器人股份有限公... 为解决SiC衬底微管缺陷检测精度低、效率差的问题,研制了基于氦质谱检漏技术的SiC衬底微管检测设备。该设备以PFEIFFER公司的ASM 340型检漏仪作为检测核心、西门子S7-1200系列可编程逻辑控制器(PLC)作为控制核心、节卡机器人股份有限公司的JAKA Zu@7型机器人作为自动搬运系统,实现SiC衬底微管缺陷的全自动检测。使用ANSYS Workbench仿真平台对衬底密封结构进行受力分析和计算仿真,以确保衬底在大气压作用下不会碎裂。该设备检测到的漏率最低值为3.0×10^(-10)Pa·m^(3)/s,测试速度为2.5 min/片,均显著优于漏液检测法;重复测试数据偏差小于10%,结果稳定可靠。通过瑕疵微管检测仪和奥林巴斯显微镜对SiC衬底湿法腐蚀前后状态进行检测,发现视觉技术无法准确识别贯穿微管缺陷。该设备可以显著提高SiC衬底微管的检测精度与效率,降低检测成本,对于提升SiC衬底质量具有重要意义。 展开更多
关键词 SIC衬底 微管缺陷 氦质谱检漏技术 计算仿真 西门子可编程逻辑控制器(PLC)
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飞行时间二次离子质谱技术(TOF-SIMS)在钢铁材料缺陷分析中的应用
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作者 顾佳卿 强少明 +2 位作者 李秀军 叶若如 章乃俊 《宝钢技术》 2025年第4期69-77,共9页
飞行时间二次离子质谱(time-of-flight secondary ion mass spectrometry,TOF-SIMS)作为一种高灵敏度、高分辨率的表面分析技术,在材料科学领域应用广泛。聚焦于TOF-SIMS在钢铁材料分析中的应用,探讨了其在薄膜/钝化膜分析、微量元素残... 飞行时间二次离子质谱(time-of-flight secondary ion mass spectrometry,TOF-SIMS)作为一种高灵敏度、高分辨率的表面分析技术,在材料科学领域应用广泛。聚焦于TOF-SIMS在钢铁材料分析中的应用,探讨了其在薄膜/钝化膜分析、微量元素残留、晶界富集、表面基团表征及氢元素分析等方面的潜力。凭借高空间分辨率和卓越的化学灵敏度,TOF-SIMS能提供高精度的表面成分分布、深度剖析与三维成像结果,有效克服了能量色散X射线光谱(EDS)等传统分析方法在灵敏度与元素检测范围上的局限性。通过镀锡板黄斑缺陷、ZM镀层钢板残油及BW600钢晶界元素富集等案例,展示了该技术的实际应用。特别是在氢脆研究中,TOF-SIMS能够高效、精确地表征氢在材料中的分布,为揭示氢脆机理提供了独特优势。综上,TOF-SIMS技术在钢铁材料缺陷分析中具有广阔的应用前景,可为钢铁行业提供精准的分析手段,从而推动相关领域的技术进步。 展开更多
关键词 飞行时间二次离子质谱(TOF-SIMS) 钢铁材料 缺陷分析 微量元素 氢脆 表面分析
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富血小板纤维蛋白联合自体骨植骨对牙槽骨缺损合并牙缺失种植患者骨量及骨代谢情况的影响 被引量:2
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作者 王锦华 秦铭 《临床医学研究与实践》 2025年第8期94-97,共4页
目的探讨富血小板纤维蛋白联合自体骨植骨对牙槽骨缺损合并牙缺失种植患者骨量及骨代谢情况的影响。方法选取2020年1月至2023年1月我院收治的90例牙槽骨缺损合并牙缺失种植患者,以随机数字表法将其分为对照组(45例,自体骨植骨)和观察组... 目的探讨富血小板纤维蛋白联合自体骨植骨对牙槽骨缺损合并牙缺失种植患者骨量及骨代谢情况的影响。方法选取2020年1月至2023年1月我院收治的90例牙槽骨缺损合并牙缺失种植患者,以随机数字表法将其分为对照组(45例,自体骨植骨)和观察组(45例,富血小板纤维蛋白联合自体骨植骨)。比较两组的治疗效果。结果术后3、6个月,观察组的种植体唇侧牙槽骨骨密度、种植体唇侧骨壁厚度高于对照组(P<0.05)。术后3个月,观察组的骨保护素(OPG)水平高于对照组,骨桥蛋白(OPN)、碱性磷酸酶(ALP)水平低于对照组(P<0.05)。术后6个月,观察组的牙周袋深度、附着丧失低于对照组,平均灰度值(MGVs)高于对照组(P<0.05)。观察组的完全愈合率高于对照组,局部感染率低于对照组(P<0.05)。结论富血小板纤维蛋白联合自体骨植骨可改善牙槽骨缺损合并牙缺失种植患者骨量及骨代谢情况,减轻炎症反应,且不良反应少,值得推广。 展开更多
关键词 富血小板纤维蛋白 自体骨植骨 牙槽骨缺损 牙缺失 种植 骨量 骨代谢
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Identification and screening of cardiac glycosides in Streptocaulon griffithii using an integrated data mining strategy based on high resolution mass spectrometry 被引量:6
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作者 ZHU Xiao-Yu LIU Jia-Zhuo +2 位作者 DONG Zhen-Huan FENG Feng LIU Wen-Yuan 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2018年第7期546-560,共15页
The present study was designed to develop a practical strategy to tackle the problem of lacking standard compounds and limited references for identifying structure-related compounds in Streptocaulon griffithii Hook. f... The present study was designed to develop a practical strategy to tackle the problem of lacking standard compounds and limited references for identifying structure-related compounds in Streptocaulon griffithii Hook. f., especially those in trace concentrations, with a focus on antitumor activity. The cardiac glycosides(CGs)-enriched part was determined using in vitro bioactive assays in three cancer cell lines and then isolated using macroporous resins. The MS and MS/MS data were acquired using a high performance liquid chromatography coupled with hybrid quadrupole-time of flight(HPLC-Q-TOF-MS) system. To acquire data of trace compound in the extract, a multiple segment program was applied to modify the HPLC-Q-TOF-MS method. A mass defect filter(MDF) approach was employed to make a primary MS data filtration. Utilizing a MATLAB program, the redundant peaks obtained by imprecise MDF template calculated with limited references were excluded by fragment ion classification, which was based on the ion occurrence number in the MDF-filtered total ion chromatograms(TIC). Additionally, the complete cleavage pathways of CG aglycones were proposed to assist the structural identification of 29 common fragment ions(CFIs, ion occurrence number ≥ 5) and diagnostic fragment ions(DFIs, ion occurrence number < 5). As a result, 30 CGs were filtered out from the MDF results, among which 23 were identified. This newly developed strategy may provide a rapid and effective tool for identifying structure-related compounds in herbal medicines. 展开更多
关键词 Streptocaulongriffithii CARDIAC GLYCOSIDES mass defect filter HPLC-Q-TOF-MS
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浮法玻璃密集气泡带的处理及管控
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作者 孙成海 李刚 +2 位作者 吴华亭 刘海 张方泽 《玻璃》 2025年第8期27-32,共6页
浮法玻璃生产中,气泡缺陷影响着玻璃生产的产质量,其成因及位置多种多样、难以控制。结合生产实例,对特定浮法玻璃生产线的气泡缺陷进行案例分析,通过缺陷取样判断缺陷类型,再使用问题树分析缺陷来源问题,并同步结合GIA522气泡质谱分析... 浮法玻璃生产中,气泡缺陷影响着玻璃生产的产质量,其成因及位置多种多样、难以控制。结合生产实例,对特定浮法玻璃生产线的气泡缺陷进行案例分析,通过缺陷取样判断缺陷类型,再使用问题树分析缺陷来源问题,并同步结合GIA522气泡质谱分析仪分析气泡缺陷成分,判断气泡缺陷来源并制定可行的治理措施,达到提高产品质量的目的。 展开更多
关键词 浮法工艺 气泡缺陷 GIA522气泡质谱分析仪 气泡案例
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An extended displacement discontinuity method for analysis of stress wave propagation in viscoelastic rock mass 被引量:9
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作者 L.F.Fan1,F.Ren1,G.W.Ma2 1 School of Civil and Environmental Engineering,Nanyang Technological University,Singapore,639798,Singapore 2 School of Civil and Resource Engineering,The University of Western Australia,Crawley,WA 6009,Australia 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2011年第1期73-81,共9页
An extended displacement discontinuity method (EDDM) is proposed to analyze the stress wave propagation in jointed viscoelastic rock mass (VRM).The discontinuities in a rock mass are divided into two groups.The primar... An extended displacement discontinuity method (EDDM) is proposed to analyze the stress wave propagation in jointed viscoelastic rock mass (VRM).The discontinuities in a rock mass are divided into two groups.The primary group with an average geometrical size larger than or in the same order of magnitude of wavelength of a concerned stress wave is defined as 'macro-joints',while the secondary group with a high density and relatively small geometrical size compared to the wavelength is known as 'micro-defects'.The rock mass with micro-defects is modeled as an equivalent viscoelastic medium while the macro-joints in the rock mass are modeled explicitly as physical discontinuities.Viscoelastic properties of a micro-defected sedimentary rock are obtained by longitudinally impacting a cored long sedimentary rod with a pendulum.Wave propagation coefficient and dynamic viscoelastic modulus are measured.The EDDM is then successfully employed to analyze the wave propagation across macro-joint in VRM.The effect of the rock viscosity on the stress wave propagation is evaluated by comparing the results of VRM from the presented EDDM with those of an elastic rock mass (ERM) from the conventional displacement discontinuity method (CDDM).The CDDM is a special case of the EDDM under the condition that the rock viscosity is ignored.Comparison of the reflected and transmitted waves shows that the essential rock viscosity has a significant effect on stress wave attenuation.When a short propagation distance of a stress wave is considered,the results obtained from the CDDM approximate to the EDDM solutions,however,when the propagation distance is sufficiently long relative to the wavelength,the effect of rock viscosity on the stress wave propagation cannot be ignored. 展开更多
关键词 stress wave propagation extended displacement discontinuity method (EDDM) viscoelastic rock mass (VRM) micro-defect macro-joint
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外鼻肿物34例临床分析 被引量:1
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作者 史雅文 汪李琴 殷敏 《中国耳鼻咽喉颅底外科杂志》 CAS CSCD 2024年第5期12-17,共6页
目的探讨外鼻肿物的临床流行病学特点,分析切除后缺损的修复方法及临床效果。方法回顾性分析2010年1月-2020年12月收治的34例外鼻肿物,分析肿物的发病部位、大小、病理类型、手术和修复方法等。结果本组患者,男女发病比例为1.125∶1,男... 目的探讨外鼻肿物的临床流行病学特点,分析切除后缺损的修复方法及临床效果。方法回顾性分析2010年1月-2020年12月收治的34例外鼻肿物,分析肿物的发病部位、大小、病理类型、手术和修复方法等。结果本组患者,男女发病比例为1.125∶1,男女发病率差异无统计学意义(P>0.05);外鼻恶性肿瘤中,基底细胞癌最多(16例,80%),各年龄层均有发病,恶性肿瘤的发病高峰年龄为60岁以上人群(15例,75%)。术中彻底切除肿物后,选择直接缝合15例,邻近皮瓣修复7例,转移鼻唇沟皮瓣修复10例,植皮2例。术后随访1例接受放化疗,2例接受单纯化疗。28例伤口一期愈合,鼻外观基本对称,鼻腔无明显通气功能障碍。1例行二期瘢痕修复。3例失访,3例死亡(死于老龄),2例对外鼻形态不满意。结论外鼻肿物切除彻底,很少复发,一般无需放化疗。在手术彻底切除肿瘤的基础上,依据缺损部位及程度灵活应用不同的修复方法,重建鼻部轮廓,保持鼻部外形及结构的完整性。其中鼻唇沟皮瓣修复操作方便,并发症少,患者取得满意效果,是临床常选择的治疗方案。 展开更多
关键词 外鼻肿物 缺损 鼻唇沟皮瓣 修复
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一种SiC MOSFET栅氧界面缺陷的POA优化工艺
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作者 付兴中 刘俊哲 +4 位作者 薛建红 尹志鹏 谭永亮 王德君 张力江 《半导体技术》 CAS 北大核心 2024年第12期1144-1152,共9页
栅氧界面缺陷严重影响SiC MOSFET性能。开发了一种NO氧化后退火(POA)优化工艺,采用氮、氢、氧、氯四种元素组合钝化工艺,实现对SiC MOSFET栅氧界面缺陷的抑制。通过X射线光电子能谱(XPS)、二次离子质谱(SIMS)和电学测试,对工艺优化前后... 栅氧界面缺陷严重影响SiC MOSFET性能。开发了一种NO氧化后退火(POA)优化工艺,采用氮、氢、氧、氯四种元素组合钝化工艺,实现对SiC MOSFET栅氧界面缺陷的抑制。通过X射线光电子能谱(XPS)、二次离子质谱(SIMS)和电学测试,对工艺优化前后的SiC MOSFET栅氧界面缺陷类型及器件电学特性进行了分析。测试结果表明,采用传统NO POA工艺的SiC MOSFET退火后在栅氧化层和栅氧界面中存在大量缺陷,尤其是C相关缺陷,影响器件栅氧的绝缘特性。POA优化工艺对SiC MOSFET栅氧界面缺陷具有明显的抑制作用,可极大地提高N元素对栅氧界面缺陷的钝化效果,并且抑制了O空位的形成,进而提升了器件的可靠性和迁移率,降低了界面态密度,对器件性能起到了较好的优化效果。 展开更多
关键词 SiC MOSFET X射线光电子能谱(XPS) 二次离子质谱(SIMS) 界面缺陷 氧化后退火(POA)
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Identification and trimming of the unbalanced mass in micro hemispherical resonators based on an elastic electrode substrate
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作者 Yimo Chen Yan Shi +4 位作者 Xiang Xi Yang Yu Kun Lu Dingbang Xiao Xuezhong Wu 《Microsystems & Nanoengineering》 2025年第2期343-354,共12页
This study presents a scheme for the identification and trimming of the first three harmonics of mass defects in micro hemispherical resonators(MHRs),aiming to refine their mass balancing techniques.Given the manufact... This study presents a scheme for the identification and trimming of the first three harmonics of mass defects in micro hemispherical resonators(MHRs),aiming to refine their mass balancing techniques.Given the manufacturing and structural uniqueness of MHRs,a multimodal elastic electrode substrate is designed to respond to the first three harmonics.Configured as cantilever beams with a load platform,this substrate forms an identification assembly with the MHR.The radial eccentric forces generated by the 1st and 3rd harmonics in the MHR can excite the swing modes of the assembly,while the axial force generated by the 2nd harmonic can induce axial mode vibrations along the Z-axis.A method is proposed to decompose the vibration information of the elastic electrode substrate into doublecycle,single-cycle,and offset components under the N=2 modes,enabling the extraction of swing mode and Z-axis translational mode response signals and the retro-calculation of the first three harmonics.Finite element simulation,based on a model of the identification assembly,validates the proposed scheme by simulating the identification and trimming process.Subsequently,an identification assembly sample is fabricated and subjected to identification and trimming of the first three harmonics using a laser vibrometer and femtosecond laser ablation process.After multiple iterations,the first three harmonics are reduced by 92.8%,89.3%,and 75.5%,respectively,effectively suppressing the swing modes and axial translation modes induced by unbalanced mass. 展开更多
关键词 refine their mass balancing techniquesgiven IDENTIFICATION micro hemispherical resonators mhrs aiming multimodal elastic electrode substrate cantilever beams load platformthis trimming first three harmonics mass defects radial eccentric forces
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涂料传热、传质过程与铸件缺陷控制 被引量:1
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作者 宋会宗 《现代铸铁》 CAS 2024年第2期51-53,59,共4页
介绍了涂料在干燥和浇注过程中的传热、传质过程,分析了传热、传质过程对涂料的干燥、抗脉纹、防硫等作用的重要影响,指出:(1)对流+红外辐射换热具有最佳的烘干效率,对砂芯质量的影响最小;(2)涂料的导热性影响砂芯的高温强度及保持时间... 介绍了涂料在干燥和浇注过程中的传热、传质过程,分析了传热、传质过程对涂料的干燥、抗脉纹、防硫等作用的重要影响,指出:(1)对流+红外辐射换热具有最佳的烘干效率,对砂芯质量的影响最小;(2)涂料的导热性影响砂芯的高温强度及保持时间、硅砂相变膨胀、热应力、温差,进而影响到铸件脉纹、石墨衰退、结疤、粘砂等一系列缺陷;(3)通过特殊设计的涂料成分可以控制涂料的传热和传质过程,使涂料具有防止某种缺陷的功能。 展开更多
关键词 涂料 传热 传质 缺陷
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含双垂直缺陷岩体爆生裂纹扩展行为试验研究 被引量:2
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作者 刘钊 张树辉 臧小静 《爆破》 CSCD 北大核心 2024年第1期21-26,66,共7页
为探究在爆炸载荷作用下含两条垂直预制缺陷岩体的爆生裂纹扩展行为,采用数字激光焦散线方法开展了一系列双垂直裂隙模型爆破实验,展现了爆生裂纹演化过程,揭示了单孔装药量对含缺陷岩体裂纹扩展行为(裂纹扩展长度、应力强度因子、扩展... 为探究在爆炸载荷作用下含两条垂直预制缺陷岩体的爆生裂纹扩展行为,采用数字激光焦散线方法开展了一系列双垂直裂隙模型爆破实验,展现了爆生裂纹演化过程,揭示了单孔装药量对含缺陷岩体裂纹扩展行为(裂纹扩展长度、应力强度因子、扩展速度和起裂时间等)的影响规律。研究结果表明:随着单孔装药量增加,双垂直裂隙端部的裂纹扩展长度、裂纹扩展速度、裂纹起裂韧度和应力强度因子均呈增加趋势。对于裂纹J_(u),单孔的药量对裂纹扩展速度影响较小,并且裂纹扩展极限速度约为横波速度的0.38倍;对于迎爆端裂纹D_(l)和背爆端裂纹D_(r),随着单孔药量的增加,裂纹D_(l)和D_(r)的起裂时间减小,但裂纹D_(l)和裂纹D_(r)的峰值应力强度因子增大。相比于裂纹D_(l),裂纹D_(r)的应力强度因子和扩展长度增加显著。当爆炸应力波作用于缺陷B两端部的能量足以使两侧裂纹扩展时,裂纹D_(l)比裂纹D_(r)先起裂。单孔药量的增加能够增大裂纹D_(r)的扩展速度,但是对裂纹D_(l)扩展速度影响较小。研究结果可为含缺陷岩体在爆破荷载作用下的断裂行为提供实验参考,有助于含缺陷岩体爆破安全设计工作。 展开更多
关键词 焦散线 缺陷岩体 爆破 装药量 裂纹扩展
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剖宫产术后子宫瘢痕憩室相关盆腔包块一例
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作者 延超凡 薛卢嘉黛 +1 位作者 王晓玉 李虎 《海南医学》 CAS 2024年第23期3474-3476,共3页
剖宫产术后子宫瘢痕憩室属于剖宫产术后长期并发症之一,主要症状为异常子宫出血、继发性不孕、慢性盆腔痛等。本文以一例育龄期妇女剖宫产术后子宫瘢痕憩室相关性盆腔肿物为报道内容,并复习相关文献来介绍该类疾病。
关键词 剖宫产术后 并发症 子宫瘢痕憩室 盆腔包块
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