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Exploration of the mechanism of cavitation vortex rope and vortex development in the draft tube of tubular turbine units

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 163-171,F0002页

作者： chuang cheng Zhenggui Li Changrong Shen Shenglong Gu Chuchu Zeng Chuanzheng Bai Meng Liu Junfeng Hu Qinghai University of Science and Technology Xining 810000China Key Laboratory of Fluid and Power Machinery Ministry of Education(Xihua University)Chengdu 610039China South-to-North Water Diversion East Jiangsu Water Source Co. Ltd.Nanjing 210029China School of civil engineering and water resources Qinghai UniversityXining 810016China Dongyuan Branch of Shenzhen Water Planning and Design Institute Co. Ltd.Changsha 410000China

Draft tube vortex rope is considered a special cavitation flow phenomenon in tubular turbine *** vortex rope is one of the most detrimental factors affecting the safety of hydraulic *** this study,ANSYS CFX software was utilized to numerically simulate the internal cavitation flow of a hydraulic turbine draft *** evolution of the cavitation vortex core was characterized by vortex line distribution and vorticity transport *** shape and number of blades influenced the revolving direction and distribution characteristics of the vortex close to the runner cone,which formed a counterclockwise-clockwise-counterclockwise distribution ***,there were many secondary flows in the draft *** cancellation and dissipation between the flows was one of the reasons for reduction in *** the cross-sectional shape of the draft tube was changed,the vorticity was distributed from the center of the vortex rope to all parts of the cross-sectional draft tube,with extreme values at the center and at the *** vortex stretching and dilatation terms played a major role in the change in vorticity,with the baroclinic torque having an effect at the center of the vortex rope,this study is helpful to understand the flow of water in the draft tube and guide the design and optimization of the draft tube in engineering application.

关键词： cavitation vortex rope vorticity transport equation vortex line draft tube

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CT引导下^(125)I粒子植入联合TACE+射频消融治疗肝包膜下小肝癌的价值

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中国CT和MRI杂志 2024年第2期22卷 111-113页

作者：王健庄崔创撑三二〇一医院核医学科陕西汉中723000 西安市第九医院放射医学科陕西西安710054

目的探讨计算机断层扫描(CT)引导下放射性^(125)I粒子植入联合肝动脉化疗栓塞(TACE)+射频消融治疗肝包膜下小肝癌的价值。方法选取2020年1月-2022年2月收治的80例肝包膜下小肝癌患者,随机分为观察组和对照组各40例,对照组采用TACE+射频... 详细信息

目的探讨计算机断层扫描(CT)引导下放射性^(125)I粒子植入联合肝动脉化疗栓塞(TACE)+射频消融治疗肝包膜下小肝癌的价值。方法选取2020年1月-2022年2月收治的80例肝包膜下小肝癌患者,随机分为观察组和对照组各40例,对照组采用TACE+射频消融术治疗,观察组在对照组的基础上采用CT引导下^(125)I粒子植入治疗,比较两组客观缓解率(ORR)、肝功能[谷丙转氨酶(ALT)、天冬氨酸转氨酶(AST)和总胆红素(TBil)]、血清肿瘤标志物[甲胎蛋白(APF)、癌胚抗原(CEA)]、不良反应以及无进展生存率。结果观察组ORR高于对照组(85.00%vs 62.50%,χ^(2)=5.230,P0.05);治疗后,观察组APF、CEA水平低于对照组(t=7.616;t=8.938,P0.05);观察组1年无进展生存率为80.00%,高于对照组的50.00%(Log Rankχ^(2)=7.487,P<0.05)。结论CT引导下^(125)I粒子植入联合TACE+射频消融治疗肝包膜下小肝癌的疗效显著,可有效降低血清肿瘤标志物水平,提高无进展生存率,且安全性较好。

关键词：小肝癌放射性^(125)I粒子肝动脉化疗栓塞射频消融术

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A novel energetic framework with the combination of 5,6-fused triazolo-triazine and nitropyrazole-tetrazole for energy-stability balanced explosive

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Defence Technology(防务技术) 2023年第9期27卷 184-192页

作者： cheng-chuang Li Hao Gu Jie Tang Guo-jie Zhang Guang-bin cheng Hong-wei Yang School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China

In recent years,the introduction of fused rings own high density and low sensitivity has promoted the development of energetic ***,the development of energetic compounds containing fused and bridged rings by introducing multiple nitrogen heterocycles at different sites of fused rings is still difficult to progress,which seriously limits the emergence of advanced energetic *** this study,a series of energetic materials choosing different nitrogen rich heterocycles at the vacancies of the fused ring,i.e.,neutral compound 5,6 and their ionic derivatives(compounds 7-12)were designed and *** 5 and 6 were further confirmed by single crystal X-ray diffraction,while the crystal analysis and theoretical calculations were carried out to explore the relationship between crystal structure and physicochemical *** of the newly synthesized compounds(5-12)are insensitive to mechanical stimulation(IS>40 J;FS≥342 N)and they own the high detonation velocity(D:8322-9075 m/s).Notably,hydrazine salt 11 own the higher detonation velocity(9075 m/s)and powder density(1.83 g/cm^(3)),but exhibits lower sensitivity(IS>40 J)than the classical energetic compound RDX(8795 m/s,1.80 g/cm^(3),7.5 J).It is obvious that the combination of 5,6-fused triazolo-triazine and nitropyrazole-tetrazole may be a new energetic skeleton for synthesising the heterocyclic compounds with balanced energy-stability.

关键词： Fused and bridged rings Energetic skeleton Balanced energy-stability Energetic materials

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Divalent nitrogen-rich cationic salts with great gas production capacities

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Defence Technology（防务技术） 2023年第4期22卷 54-68页

作者： Hao Gu cheng-chuang Li Chang-hao Dai Dong-xu Chen Hong-wei Yang Guang-bin cheng School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyXiaolingwei 200Nanjing210094PR China

Monocyclic nitrogen-rich 3-(aminomethyl)-4,5-diamine-1,2,4-triazole(1)and fused cyclic 3,7-diamine-6-(aminomethyl)-[1,2,4]triazolo[4,3-b][1,2,4]triazole(9)were synthesized through the convenient cyclization reaction from the readily available *** energetic salts with high nitrogen content were proved to be rare examples of divalent monocyclic/fused cyclic cationic salts according to the single crystal *** structure of intermediate B was also identified and verified by its trivalent cation crystal 17.5H_2O *** compounds 2-8 and 10-17 were fully characterized by NMR spectroscopy,infrared spectroscopy,differential scanning calorimetry,elemental *** energetic salts exhibit good thermal stability with decomposition temperatures ranged from 182℃to 245℃.The sensitivity of compounds 2,6,10 and 14 is similar or superior to that of RDX while the others were much more insensitive to mechanical ***,detonation velocity of 10(8843 m/s)surpass that of RDX(D=8795 m/s).Considering the high gas production volume(≥808 L/kg)of 2,4,10and 12,constant-volume combustion experiments were conduct to evaluate their gas production capacities *** compounds possess much higher maximum gas-production pressures(P_(max):7.88-10.08 MPa)than the commonly used reagent guanidine nitrate(GN:P_(max)=4.20 MPa),which indicate their strong gas production capacity.

关键词： Fused cyclic compound Triazole Divalent cation Gas production Energetic materials

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Determination and Comparison of M_(L),M_(S_BB),m_(B),M_(Wp),M_(WW),M_(dt),and M(GNSS)for the 22 May 2021 M7.4 Madoi,Qianghai,China Earthquake

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Journal of Earth Science 2022年第4期33卷 847-856页

作者： Xiaolin Huang Yuyang Peng chuang cheng Dun Wang Qiang Yao State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan 430074China

The 2021 Madoi M7.4 Earthquake in Qinghai is a major earthquake that occurred in the Bajankara Block of Qinghai-Tibet Plateau in the past 30 years,which spatially filled the seismogenic gap in the eastern section of the northern boundary of the *** we determined the values of M_(L),M_(S_BB),m_(B),M_(Wp),M_(WW),M_(dt),and M(GNSS)by abundant regional and global seismic and geodetic observations,which is 6.61,7.43,7.18,7.33,7.43,7.38,and 7.4,*** compare the time efficiency and stability of different magnitude scales,we generated a real-time environment,to iteratively determine the magnitudes over elapsed *** methods such as m_(B),M_(S_BB),M_(Wp) gave considerable variations of as large as 0.5 units for the determined magnitudes with elapsed time,as more data were *** such as M_(WW) and M_(dt) were very stable with increasing data over *** systematic calculations of various magnitude scales in this study quantitively evaluated the stability and accuracy of those methods,shading light on the adaptability and applicability of different magnitude scales.

关键词： the 2021 Madoi Earthquake earthquake magnitude magnitude scale earthquakes

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电感耦合等离子体质谱法测定注射用芝麻油中10种无机元素含量

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中国药业 2024年第8期33卷 88-91页

作者：黄华郑明何志刚程闯浙江省衢州市食品药品检验研究院浙江衢州324000 浙江龙游聚兴医药科技有限公司浙江衢州324400

目的建立测定注射用芝麻油中10种无机元素含量的电感耦合等离子体质谱(ICP-MS)法。方法采用微波消解法前处理样品,采用ICP-MS内标标准曲线法检测各元素含量,射频功率为1500 W,雾化室温度为2℃,采用氦碰撞模式,载气(氩气)流速为0.8 L/mi... 详细信息

目的建立测定注射用芝麻油中10种无机元素含量的电感耦合等离子体质谱(ICP-MS)法。方法采用微波消解法前处理样品,采用ICP-MS内标标准曲线法检测各元素含量,射频功率为1500 W,雾化室温度为2℃,采用氦碰撞模式,载气(氩气)流速为0.8 L/min。结果铅、镉、砷、汞、钴、钒、镍、锂、锑、铜质量浓度分别在1.25~12.5 ng/mL、0.50~5.0 ng/mL、4.00~40.0 ng/mL、0.75~7.5 ng/mL、1.25~12.5 ng/mL、2.50~25.0 ng/mL、5.00~50.0 ng/mL、62.50~625.0 ng/mL、22.50~225.0 ng/mL、75.00~750.0 ng/mL范围内与各元素和内标仪器响应值比值线性关系良好(r>0.9900),检测限为0.0002~0.0420μg/g,定量限为0.075~7.5μg/g;精密度、重复性试验结果的RSD均小于10%;平均加样回收率为78.64%~110.39%,RSD为1.40%~6.41%(n=9)。结论所建立的方法灵敏,结果准确可靠,可用于注射用芝麻油中10种无机元素含量的测定。

关键词：电感耦合等离子体质谱法注射用芝麻油无机元素含量测定

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空心螺钉联合锚钉治疗坐骨结节骨骺撕脱性骨折1例

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生物骨科材料与临床研究 2024年第4期21卷 91-93页

作者：项飞潘波程创丁吉博王建广新疆喀什地区第二人民医院骨科新疆喀什844000.91

坐骨结节撕脱性骨折(avulsion fracture of ischial tuberosity,AFIT)是通常发生在骨骼尚未发育成熟的运动员身上的一种较为少见的损伤^([1]),由于膝关节伸展时突然用力屈曲使半腱肌、半膜肌或股二头肌强烈收缩,导致坐骨结节骨折并出现... 详细信息

坐骨结节撕脱性骨折(avulsion fracture of ischial tuberosity,AFIT)是通常发生在骨骼尚未发育成熟的运动员身上的一种较为少见的损伤^([1]),由于膝关节伸展时突然用力屈曲使半腱肌、半膜肌或股二头肌强烈收缩,导致坐骨结节骨折并出现骨折块移位。关于AFIT治疗策略的选择,医学界尚未达成共识。部分学者推荐保守治疗,强调其低风险和非侵入性特点^([2]);而另一些学者则主张手术治疗,认为其对严重或复杂病例更为有效^([3])。

关键词：撕脱性骨折坐骨结节复杂病例半膜肌空心螺钉非侵入性骨折块移位股二头肌

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Fabrication and properties of well-ordered arrays of single-crystalline NiSi2 nanowires and epitaxial NiSi2/Si heterostructures

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Nano Research 2014年第11期7卷 1592-1603页

作者： Chenfu chuang Shaoliang cheng Department of Chemical and Materials Engineering Central University Chung-Li City Taoyuan 32001

在这研究，我们报导了 wellordered 数组的设计，制造，和描述垂直地排列，取向附生非最后 2 /Si heterostructures 并且单人赛水晶非最后 2 nanowires 在上(001 ) Si 底层。取向附生非最后有 \ 的 2 (\{\bar 111 \}\) 方面被发现... 详细信息

在这研究，我们报导了 wellordered 数组的设计，制造，和描述垂直地排列，取向附生非最后 2 /Si heterostructures 并且单人赛水晶非最后 2 nanowires 在上(001 ) Si 底层。取向附生非最后有 \ 的 2 (\{\bar 111 \}\) 方面被发现是第一并且唯一的 silicide 阶段在在象 300 琠敨攠癮一样低的温度退火以后在 Si nanowires 内形成了？？

关键词：单晶体结构镍纳米线有序排列异质结构结构性能垂直排列硅化程度 Si衬底

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Determination and comparison of M， M， m， M， M， M， and M（GNSS） for the 22 May 2021 Mw 7.3 Madoi， Qianghai， China earthquake

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Journal of Earth Science 2022年

作者： Xiaolin Huang Qiang Yao Yuyang Peng chuang cheng Dun Wang State Key Laboratory of Geological Processes and Mineral Resources， School of Earth Sciences， China University of Geosciences

The 2021 Madoi M7.3 earthquake in Qinghai is a major earthquake that occurred in the Bajankara block of Qinghai-Tibet Plateau in the past 30 years， which spatially filled the seismogenic gap in the eastern section of the northern boundary of the block. Here we determined the values of M， M， m， M， M， M， and M （GNSS） by abundant regional and global seismic and geodetic observations， which is 6.61， 7.43， 7.18， 7.33， 7.43， and 7.38， respectively. To compare the time efficiency and stability of different magnitude scales， we generated a real-time environment， to iteratively determine the magnitudes over elapsed times. Some methods such as m， M， Mgave considerable variations of as large as 0.5 units for the determined magnitudes with elapsed time， as more data were included. Others such as Mand Mwere very stable with increasing data over time. The systematic calculations of various magnitude scales in this study quantitively evaluated the stability and accuracy of those methods， shading light on the adaptability and applicability of different magnitude scales.

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Combined use of fly ash and silica to prevent the long-term strength retrogression of oil well cement set and cured at HPHT conditions

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Petroleum Science 2024年第2期21卷 1122-1134页

作者： Guo-Dong cheng Xue-Yu Pang Jin-Sheng Sun Zheng-Song Qiu chuang-chuang Wang Jian-Kun Qin Ning Li School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Oil and Gas Engineering Research Institute(Tarim Oilfield Company) China National Petroleum CorporationTarim841000XinjiangChina

The long-term strength retrogression of silica-enriched oil well cement poses a significant threat to wellbore integrity in deep and ultra-deep wells, which is a major obstacle for deep petroleum and geothermal energy development. Previous attempts to address this problem has been unsatisfactory because they can only reduce the strength decline rate. This study presents a new solution to this problem by incorporating fly ash to the traditional silica-cement systems. The influences of fly ash and silica on the strength retrogression behavior of oil well cement systems directly set and cured under the condition of 200°C and 50 MPa are investigated. Test results indicate that the slurries containing only silica or fly ash experience severe strength retrogression from 2 to 30 d curing, while the slurries containing both fly ash and silica experience strength enhancement from 2 to 90 d. The strength test results are corroborated by further evidences from permeability tests as well as microstructure analysis of set cement. Composition of set cement evaluated by quantitative X-ray diffraction analyses with partial or no known crystal structure(PONKCS) method and thermogravimetry analyses revealed that the conversion of amorphous C-(A)-S-H to crystalline phases is the primary cause of long-term strength *** addition of fly ash can reduce the initial amount of C-(A)-S-H in the set cement, and its combined use with silica can prevent the crystallization of C-(A)-S-H, which is believed to be the working mechanism of this new admixture in improving long-term strength stability of oil well cement systems.

关键词： Fly ash Long-term strength retrogression High temperature Quantitative X-ray diffraction(QXRD) Partial or no known crystal structure(PONKCS)

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