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Characteristics of laser-induced breakdown spectroscopy of liquid slag
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作者 董长言 于洪霞 +4 位作者 孙兰香 李洋 刘修业 周平 黄少文 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期86-93,共8页
Rapid online analysis of liquid slag is essential for optimizing the quality and energy efficiency of steel production. To investigate the key factors that affect the online measurement of refined slag using laser-ind... Rapid online analysis of liquid slag is essential for optimizing the quality and energy efficiency of steel production. To investigate the key factors that affect the online measurement of refined slag using laser-induced breakdown spectroscopy(LIBS), this study examined the effects of slag composition and temperature on the intensity and stability of the LIBS spectra. The experimental temperature was controlled at three levels: 1350℃, 1400℃, and 1450℃. The results showed that slag composition and temperature significantly affected the intensity and stability of the LIBS spectra. Increasing the Fe content and temperature in the slag reduces its viscosity, resulting in an enhanced intensity and stability of the LIBS spectra. Additionally, 42 refined slag samples were quantitatively analyzed for Fe, Si, Ca, Mg, Al, and Mn at 1350℃, 1400℃, and 1450℃.The normalized full spectrum combined with partial least squares(PLS) quantification modeling was used, using the Ca Ⅱ 317.91 nm spectral line as an internal standard. The results show that using the internal standard normalization method can significantly reduce the influence of spectral fluctuations. Meanwhile, a temperature of 1450℃ has been found to yield superior results compared to both 1350℃ and 1400℃, and it is advantageous to conduct a quantitative analysis of the slag when it is in a “water-like” state with low viscosity. 展开更多
关键词 laser-induced breakdown spectroscopy(LIBS) SLAG temperature COMPOSITION VISCOSITY internal standard normalization partial least squares(PLS)
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Time-resolved ultra-small-angle X-ray scattering beamline(BL10U1)at SSRF
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作者 Wen-Qiang Hua Chun-Ming Yang +12 位作者 ping zhou Feng Tian Jin-You Lin Yu-Zhu Wang Xiao-Yun Li Xia-Ran Miao Chun-Xia Hong Qiu-Shi Huang Xin-Tong Zhao Yong-Feng Men Jie Wang Xing-Yu Gao Xiu-Hong Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期6-19,共14页
The construction of a new beamline,BL10U1,was completed at the Shanghai synchrotron radiation facility in 2020.This multipurpose beamline was designed to provide X-ray scattering techniques such as ultra-small-angle X... The construction of a new beamline,BL10U1,was completed at the Shanghai synchrotron radiation facility in 2020.This multipurpose beamline was designed to provide X-ray scattering techniques such as ultra-small-angle X-ray scattering(USAXS),small-angle X-ray scattering(SAXS),wide-angle X-ray scattering,and microfocus SAXS(μSAXS)for a broad user community.To realize fast time-resolved USAXS experiments,the beamline adopted an in-vacuum undulator with a total length of 1.6 m as the photon source.An in-house cryogenic-cooled double multilayer monochromator was installed to deliver a photon flux of approximately 10^(13) photons/s at a photon energy of 10 keV.The three-year successful operation of this beamline demonstrated that the monochromator operated smoothly,as expected.BL10U1 has three end stations in succession:USAXS end station,μSAXS end station,and end station for industrial applications.The minimum scattering vector q~0.0042 nm^(-1) at 10 keV can be achieved at the USAXS end station equipped with a 28 m-long and 1.8 m-diameter vacuum flight tube.At theμSAXS end station,a beam spot of less than 10×8μm was achieved for micro-SAXS experiments.In contrast,in situ experimental instruments up to 5 m high and 8 m wide can be mounted at the industrial application end station,which offers industrial scientists the opportunity to use their large industrial equipment.BL10U1 opens up a new capability to investigate phenomena such as non-equilibrium and dynamic processes of materials with a wide length scale from angstroms to micrometers with millisecond time resolution.In this paper,we also report beamline design considerations and commissioning results. 展开更多
关键词 Synchrotron radiation Ultra-small-angle X-ray scattering Micro small-angle X-ray scattering USAXS Time resolved μSAXS
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Study of the reaction mechanism for preparing powdered activated coke with SO_(2)adsorption capability via one-step rapid activation method under flue gas atmosphere
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作者 Binxuan zhou Jingcai Chang +5 位作者 Jun Li Jinglan Hong Tao Wang Liqiang Zhang ping zhou Chunyuan Ma 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期158-168,共11页
In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction m... In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction mechanism is summarized.Results indicate that the reaction process of this method can be divided into three stages:stage I is the rapid release of volatiles and the rapid consumption of O_(2),primarily occurring within a reaction time range of 0-0.5 s;stage II is mainly the continuous release and diffusion of volatiles,which is the carbonization and activation coupling reaction stage,and the carbonization process is the main in this stage.This stage mainly occurs at the reaction time range of 0.5 -2.0 s when SL-coal is used as material,and that is 0.5-3.0 s when JJ-coal is used as material;stage III is mainly the activation stage,during which activated components diffuse to both the surface and interior of particles.This stage mainly involves the reaction stage of CO_(2)and H2O(g)activation,and it mainly occurs at the reaction time range of 2.0-4.0 s when SL-coal is used as material,and that is 3.0-4.0 s when JJ-coal is used as material.Besides,the main function of the first two stages is to provide more diffusion channels and contact surfaces/activation sites for the diffusion and activation of the activated components in the third stage.Mastering the reaction mechanism would serve as a crucial reference and foundation for designing the structure,size of the reactor,and optimal positioning of the activator nozzle in PAC preparation. 展开更多
关键词 Reaction mechanism Powdered activated coke preparation SO_(2)adsorption One-step rapid activation Flue gas atmosphere
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Omental fibroma combined with right indirect inguinal hernia masquerades as a scrotal tumor: A case report
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作者 ping zhou Chan-Hui Jin +6 位作者 Ying Shi Guo-Qing Ma Wen-Hao Wu Yu Wang Kun Cai Wu-Feng Fan Tian-Bao Wang 《World Journal of Clinical Cases》 SCIE 2024年第5期988-994,共7页
BACKGROUND The most common causes of scrotal enlargement in patients include primary tumor of the scrotum,inflammation,hydrocele of the tunica vaginalis,and indirect inguinal hernia;scrotal enlargement caused by exter... BACKGROUND The most common causes of scrotal enlargement in patients include primary tumor of the scrotum,inflammation,hydrocele of the tunica vaginalis,and indirect inguinal hernia;scrotal enlargement caused by external tumors of the scrotum is rare.The patient had both a greater omentum tumor and an inguinal hernia,and the tumor protruded into the scrotum through the hernia sac,which is even rarer.Moreover,omental tumors are mostly metastatic,and primary omental fibroma is rare.CASE SUMMARY Here,we report a rare case of a 25-year-old young man with scrotal enlargement and pain for 3 months.Preoperative examination and multidisciplinary discu-ssions considered intra-abdominal tumor displacement and inguinal hernia,and intraoperative exploration confirmed that the greater omentum tumor protruded into the scrotum.Therefore,tumor resection and tension-free inguinal hernia repair were performed.The final diagnosis was benign fibroma of the greater omentum accompanied by an indirect inguinal hernia.CONCLUSION This unusual presentation of a common inguinal hernia disease illustrates the necessity of performing detailed history taking,physical examination,and imaging before surgery. 展开更多
关键词 HERNIA Indirect inguinal hernia FIBROMA Omental tumor Scrotal tumor Greater omentum Case report
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Effect of Salvia Miltiorrhiza Injection on Blood Pressure and Cardiac Function in Rats with Gestational Hypertension and Preeclampsia
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作者 Xi Zhang Juan Li +3 位作者 ping zhou Qianqian Luo Zhaojun Xiang Hongying Wu 《Journal of Biosciences and Medicines》 2023年第12期152-160,共9页
Objective: This study is to observe the effects of Salvia miltiorrhiza injection on blood pressure and cardiac function in rats with pregnancy-induced hypertension and preeclampsia. Methodology: Syncytiotrophoblast mi... Objective: This study is to observe the effects of Salvia miltiorrhiza injection on blood pressure and cardiac function in rats with pregnancy-induced hypertension and preeclampsia. Methodology: Syncytiotrophoblast microvilli (stbm) and l-arginine nitrosyl methyl ester were screened out via caudal vein injection. Twenty gestational hypertension-preeclampsia model SD (Sprague Dawley) rats successfully induced by L-NAME (L-arginine Nitrosyl methyl ester) were randomly divided into 2 groups (model group and Danshen injection group, n = 10). Then another 10 normal pregnant SD rats without model were selected as blank control group. The Salvia miltiorrhiza injection group was given Salvia miltiorrhiza injection (0.5 g?kg?1?d?1) through tail vein, and the control group and model group were given equal volume of normal saline through tail vein injection. All three groups were treated by tail vein injection once a day (d) for 7 days. After treatment, heart rate (HR), Systolic pressure (SP), diastolic pressure (DP) and mean arterial pressure (MAP) were measured by tail artery. Left ventricular end-diastolic diameter (LVDd) and Left ventricular end systolic diameter (LVDs) were recorded by echocardiography. Left ventricular end diastolic pressure (LVEDP), left ventricular systolic pressure (LVSP), left ventricular ejection fraction (left ventricular ejection) fraction, LVEF) and the maximum rate of increase/decrease of left ventricular pressure during isovolemic systole (+dp/dtmax/?dp/dtmax);Endothelin-1 (ET-1) levels in rat tail vein blood were detected by ELISA. Results: SP, DP, MP, HR, LVSP, LVDs and ?dp/dtmaxx were all decreased, plasma ET-1 expression was low, and LVDd, LVEDP, LVEF, and +dp/dtmax were all increased in the Salvia miltiorroot injection group, with statistical significance compared to the model group (p Conclusion: Salvia miltiorrhiza injection can improve the cardiac function and reduce blood pressure in rats with pregnancy-induced hypertension and preeclampsia, and the mechanism may be related to alleviating systemic arteriolar spasm by regulating ET-1 level. 展开更多
关键词 RAT Danshen Injection Pregnancy-Induced Hypertension PREECLAMPSIA ENDOTHELIN-1 Blood Pressure Cardiac Function
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Brief introduction to the historical development and therapeutic effects of cupping therapy in traditional Chinese medicine
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作者 ping zhou Wei-Jie Xie ping Zheng 《TMR Non-Drug Therapy》 2019年第1期27-34,共8页
Cupping therapy (CT) is an ancient traditional and complementary medicine practice. Recently, there has been a growing evidence of its potential benefits in the treatment of various diseases. The CT has been constantl... Cupping therapy (CT) is an ancient traditional and complementary medicine practice. Recently, there has been a growing evidence of its potential benefits in the treatment of various diseases. The CT has been constantly developing with the emergence of various modern and improved cupping devices. It is now evident that cupping could adjust the Qi, blood, Yin and Yang, dredge the meridian, as well as relieve the effect of illness, achieve fitness and relative equilibrium of Yin-Yang. It exerts its effects through the negative pressure suction via the mechanical and thermal stimulations, and the negative pressure effects induced by cupping. This article gives an overview of CT practice, its historical development, as well as its therapeutic effects and mechanism. Furthermore, a new and updated classification of CT was briefly introduced. 展开更多
关键词 CUPPING therapy THERAPEUTIC mechanisms HISTORICAL development TCM
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闪速吹炼炉内颗粒在不同操作参数下的分布与演化规律
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作者 祝振宇 周萍 +4 位作者 陈卓 周俊 万兴邦 张劲松 任鹏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第9期2866-2878,共13页
通过开展工业试验揭示闪速吹炼炉内颗粒质量和粒径的分布与演化规律,同时研究不同配风参数对颗粒分布的影响。结果表明,颗粒在反应塔内的下落过程中,其平均粒径增长通常为2~3倍,且聚并后的大颗粒主要分布在料锥中部和外部;而导致该现象... 通过开展工业试验揭示闪速吹炼炉内颗粒质量和粒径的分布与演化规律,同时研究不同配风参数对颗粒分布的影响。结果表明,颗粒在反应塔内的下落过程中,其平均粒径增长通常为2~3倍,且聚并后的大颗粒主要分布在料锥中部和外部;而导致该现象出现的原因是较高的湍流强度和颗粒分布密度、以及天然气燃烧的位置使该位置处颗粒升温熔融、并发生碰撞和聚并。另外,提高分散风与工艺风动量比能使物料颗粒在反应塔内的分布更加均匀,更有利于冰铜的氧化反应。相较于调整工艺风参数,改变分散风能更有效地提高颗粒的空间分布范围。 展开更多
关键词 工业试验 颗粒演化 质量分布 粒径分布 动量比 闪速吹炼炉
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Mitochondrial carnitine palmitoyltransferase-Ⅱ dysfunction: A possible novel mechanism for nonalcoholic fatty liver disease in hepatocarcinogenesis
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作者 Min Yao ping zhou +2 位作者 Yan-Yan Qin Li Wang Deng-Fu Yao 《World Journal of Gastroenterology》 SCIE CAS 2023年第12期1765-1778,共14页
Nonalcoholic fatty liver disease(NAFLD)or metabolic-associated fatty liver disease has been characterized by the lipid accumulation with injury of hepatocytes and has become one of the most common chronic liver diseas... Nonalcoholic fatty liver disease(NAFLD)or metabolic-associated fatty liver disease has been characterized by the lipid accumulation with injury of hepatocytes and has become one of the most common chronic liver diseases in the world.The complex mechanisms of NAFLD formation are still under identification.Carnitine palmitoyltransferase-Ⅱ(CPT-Ⅱ)on inner mitochondrial membrane(IMM)regulates long chain fatty acidβ-oxidation,and its abnormality has had more and more attention paid to it by basic and clinical research in NAFLD.The sequences of its peptide chain and DNA nucleotides have been identified,and the catalytic activity of CPT-Ⅱ is affected on its gene mutations,deficiency,enzymatic thermal instability,circulating carnitine level and so on.Recently,the CPT-Ⅱ dysfunction has been discovered in models of liver lipid accumulation.Meanwhile,the malignant transformation of hepatocyte-related CD44^(+) stem T cell activation,high levels of tumor-related biomarkers(AFP,GPC3)and abnormal activation of Wnt3a expression as a key signal molecule of the Wnt/β-catenin pathway run parallel to the alterations of hepatocyte pathology.This review focuses on some of the progress of CPT-Ⅱ inactivity on IMM with liver fatty accumulation as a possible novel pathogenesis for NAFLD in hepatocarcinogenesis. 展开更多
关键词 Carnitine palmitoyl transferase-II Nonalcoholic fatty liver disease Fatty acidβ-oxidation CARNITINE Hepatocyte malignant transformation Mitochondrial membrane
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Genome sequencing revealed the red-flower trait candidate gene of a peach landrace
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作者 ping zhou Siru Lei +5 位作者 Xiaodan Zhang Yinghao Wang Rui Guo Shaobin Yan Guang Jin Xingtan Zhang 《Horticulture Research》 SCIE CSCD 2023年第11期155-167,共13页
Peach(Prunus persica)is an economically important fruit crop globally and an excellent material for genomic studies.While considerable progress has been made in unveiling trait-associated genes within cultivars and wi... Peach(Prunus persica)is an economically important fruit crop globally and an excellent material for genomic studies.While considerable progress has been made in unveiling trait-associated genes within cultivars and wild relatives,certain novel genes controlling valuable traits in peach landraces,such as the red-flowering gene,remained unclear.In this study,we sequenced and assembled the diploid genome of the red-flower landrace‘Yingzui’(abbreviated as‘RedY’).Multi-omics profiling of red petals of‘RedY’revealed the intensified red coloration associated with anthocyanins accumulation and concurrent decline in f lavonols.This phenomenon is likely attributed to a natural variant of Flavonol Synthase(FLS)harboring a 9-bp exonic insertion.Intriguingly,the homozygous allelic configurations of this FLS variant were only observed in red-flowered peaches.Furthermore,the 9-bp sequence variation tightly associated with pink/red petal color in genome-wide association studies(GWAS)of collected peach germplasm resources.Functional analyses of the FLS variant,purified from procaryotic expression system,demonstrated its diminished enzymatic activity in f lavonols biosynthesis,impeccably aligning with the cardinal trait of red flowers.Therefore,the natural FLS variant was proposed as the best candidate gene for red-f lowering trait in peach.The pioneering unveiling of the red-flowered peach genome,coupled with the identification of the candidate gene,expanded the knowledge boundaries of the genetic basis of peach traits and provided valuable insights for future peach breeding efforts. 展开更多
关键词 intensified FLOWERS PEACH
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Research progress on the role of cold-sensitive channel TRPM8 in controlling low temperature-induced bone metabolic imbalance
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作者 Yimeng Zhang Kazakova E.V +1 位作者 Huijuan Chai ping zhou 《Frigid Zone Medicine》 2023年第4期202-208,共7页
With increasing aging population,osteoporosis has emerged as a public health problem worldwide.Epidemiological data reveal that the prevalence of osteoporosis in cold regions is high,and low temperatures may crucially... With increasing aging population,osteoporosis has emerged as a public health problem worldwide.Epidemiological data reveal that the prevalence of osteoporosis in cold regions is high,and low temperatures may crucially affect bone mass.Recent studies have found that the transient receptor potential melastatin-8(TRPM8)channel,a cold-sensitive ion channel,can sense cold environment,and can be activated in cold environment.It may play an antagonistic role in low temperature-induced bone mass reduction.Mechanistically,this function may be ascribed to the activation of TRPM8 channel proteins in human bone marrow mesenchymal stem cells(hBM-MSCs),which causes osteoblast differentiation and mineralization in the bone.TRPM8 channel on the surface of brown adipocytes participates in the thermogenesis in brown adipose tissue(BAT)and the regulation of whole-body energy balance to maintain bone homeostasis.TRPM8 may be involved in bone remodeling throughout life.This paper reviews recent research on the possible antagonistic mechanism of TRPM8 in signaling pathways related to low temperature-induced bone mass loss and assesses the possibility of TRPM8 as a molecular target for the prevention and treatment of low temperature-induced osteoporosis in cold regions. 展开更多
关键词 TRPM8 low temperature OSTEOPOROSIS bone mass
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基于血栓弹力图抗栓治疗动脉粥样硬化性脑梗死的疗效分析 被引量:17
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作者 葛中林 钱明月 +6 位作者 周萍 谭玉 伏兵 张照婷 张浩江 庄爱霞 陈皆春 《中国现代医学杂志》 CAS 2019年第11期78-83,共6页
目的探讨基于血栓弹力图(TEG)抗栓治疗急性动脉粥样硬化性脑梗死的疗效。方法选取连云港市第二人民医院收治的184例急性动脉粥样硬化性脑梗死(ACI)患者。随机分为:A组,阿司匹林抗栓治疗;B组,氯吡格雷抗栓治疗;C组,氯吡格雷联合阿司匹林... 目的探讨基于血栓弹力图(TEG)抗栓治疗急性动脉粥样硬化性脑梗死的疗效。方法选取连云港市第二人民医院收治的184例急性动脉粥样硬化性脑梗死(ACI)患者。随机分为:A组,阿司匹林抗栓治疗;B组,氯吡格雷抗栓治疗;C组,氯吡格雷联合阿司匹林抗栓治疗;D组,用血栓弹力图仪检测血小板抑制率,选择血小板抑制率高的抗栓药物治疗,每组46例。比较患者治疗前后神经功能缺损评分(NIHSS)、日常生活能力评分(ADL)、微栓子(MES)阳性率改善情况,统计卒中复发率及出血性事件的发生率。结果治疗后4组患者的NIHSS评分下降,而ADL评分提高(P<0.05),且治疗后C、D组NIHSS评分低于A、B组,ADL评分高于A、B组(P <0.05)。治疗后,C、D两组临床治疗有效率高于A组(P<0.0167)。治疗后,4组患者的MES阳性率均降低(P<0.05),且C组MES阳性率均低于A、B组(P<0.0167)。4组胃肠道不适、病死率比较,差异无统计学意义(P>0.05);治疗后C、D两组复发率低于A组(P <0.0167),但C、D两组间比较,差异无统计学意义(P>0.05)。出血事件B、D两组低于C组(P <0.0167)。结论采用基于血栓弹力图个体化治疗ACI的抗栓效果优于阿司匹林和氯吡格雷单用,同时能够有效降低双抗药物联合治疗带来的出血性事件风险。 展开更多
关键词 梗塞 大脑中动脉 血栓弹力图 氯吡格雷 阿司匹林 动脉粥样硬化 微栓子
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水域底泥中重金属Cd与Pb释放规律的数值模拟 被引量:5
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作者 闫红杰 张河杨 +4 位作者 史雅君 周萍 李欢 伍东玲 刘柳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第1期277-287,共11页
采用实验研究与数值模拟相结合的方法,研究某水域底泥中典型重金属污染物Cd与Pb再释放过程和释放速率。结果表明,底泥中Cd和Pb的释放规律分为快速释放和动态平衡两个阶段,与准二级动力学方程具有较好的匹配度,相关系数R2大于0.99。随着... 采用实验研究与数值模拟相结合的方法,研究某水域底泥中典型重金属污染物Cd与Pb再释放过程和释放速率。结果表明,底泥中Cd和Pb的释放规律分为快速释放和动态平衡两个阶段,与准二级动力学方程具有较好的匹配度,相关系数R2大于0.99。随着河流流速的加快,底泥中重金属的释放速率增大。分析表明,该区域水质可以在3 h内超过地表水环境质量V类标准。数值模拟结果与实测值之间的相对偏差除一项外均在±10%以内。 展开更多
关键词 底泥 重金属污染 再释放率 数值模拟
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不同进液方式下铜电解槽内电解液流动特性的评价(英文) 被引量:3
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作者 周萍 马海博 +2 位作者 谢紫微 闫红杰 Chenn Q.zhou 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第10期2282-2290,共9页
铜电解槽的进液口布置方式对极板间的流场有着显著的影响,而流场的分布决定电解过程中的电流分布。为了深入了解电解液在竖直极板间复杂的流动行为,以铜电解槽为研究对象,建立了针对"一端进液"、"底部中心进液"、&q... 铜电解槽的进液口布置方式对极板间的流场有着显著的影响,而流场的分布决定电解过程中的电流分布。为了深入了解电解液在竖直极板间复杂的流动行为,以铜电解槽为研究对象,建立了针对"一端进液"、"底部中心进液"、"上侧交错进液"和"底部交错进液"4种不同进液方式下电解槽内电解液的流动过程的三维计算流体动力学模型并进行数值模拟。结果表明:由于"底部中心进液"式电解槽中进液口的位置分布不均匀,其速度的极差较大,是交错进液时的4倍以上。另外,由于"底部交错进液"式电解槽内电解液的湍流强度较大,因此其体平均速度是"一端进液"式的4倍。综合来看,"底部交错进液"式电解槽能够将新鲜的电解液快速、均匀地补充到极板间,为提高电流密度和增加产能奠定了基础。 展开更多
关键词 铜电解精炼 进液口布置方式 流场均匀性 计算流体力学
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卧式搅拌釜气液两相流场的参数化研究 被引量:6
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作者 陈志彬 闫红杰 +4 位作者 周萍 杨平 丁杰辉 刘佳 刘柳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第6期1806-1817,共12页
基于Fluent软件,采用SST k−ω湍流模型、欧拉−欧拉两相流模型和多重参考系法对卧式搅拌釜气液两相流场进行数值模拟,并采用示踪剂法研究釜内混合过程。结果表明:增大转速或气体流量有利于气相分布更均匀并加快液相的混合。当搅拌转速超... 基于Fluent软件,采用SST k−ω湍流模型、欧拉−欧拉两相流模型和多重参考系法对卧式搅拌釜气液两相流场进行数值模拟,并采用示踪剂法研究釜内混合过程。结果表明:增大转速或气体流量有利于气相分布更均匀并加快液相的混合。当搅拌转速超过93 r/min时,相对功率消耗基本不变。上叶轮倾斜角的变化对气相分布的影响很小。当倾角为50°时,相对功率消耗最大。适当提高桨叶离底高度可以提高气含率并改善气相分布,但会增加液相混匀时间。 展开更多
关键词 卧式搅拌釜 气液两相流 欧拉−欧拉两相流模型 多重参考系法
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端淬冷却过程的实验及CFD研究(英文) 被引量:4
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作者 付佩 周萍 +2 位作者 谢紫微 吴红宇 陈继光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第11期2440-2446,共7页
合金的显微组织很大程度上受其冷却过程的影响。为了建立一种先进镍基高温合金材料的冷却速率及对应微观结构的关系,采用实验和数值模拟的方法研究其冷却过程。实验测量数据包含工件在端淬过程中的温度及其后的二次γ′相的尺寸。通过... 合金的显微组织很大程度上受其冷却过程的影响。为了建立一种先进镍基高温合金材料的冷却速率及对应微观结构的关系,采用实验和数值模拟的方法研究其冷却过程。实验测量数据包含工件在端淬过程中的温度及其后的二次γ′相的尺寸。通过导热反问题方法确定模拟所需的端淬表面换热系数。结果表明,端淬表面换热系数超过1574 K/min。基于模拟所得的平均冷却速率和实验所得的二次γ′相的尺寸数据,建立两者间的双对数关系式,其可靠性通过特定冷却速率的实验得到验证。 展开更多
关键词 端淬实验 数值模拟 冷却速率 换热系数 镍基高温合金
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基夫赛特熔炼过程中供氧方式的CFD模拟与优化(英文) 被引量:3
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作者 李家栋 周萍 +3 位作者 廖舟 柴立元 Chenn Q.zhou 张岭 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第7期1560-1568,共9页
通过数值模拟研究供氧方式对基夫赛特熔炼过程的影响。以中央喷射分配喷嘴的中央氧与侧氧质量流量比表示供氧方式,模拟质量流量比在 0.09~0.39 范围内的基夫赛特炉熔炼过程。结果表明,4 个中央喷射分配喷嘴下方区域为高效反应区。增大... 通过数值模拟研究供氧方式对基夫赛特熔炼过程的影响。以中央喷射分配喷嘴的中央氧与侧氧质量流量比表示供氧方式,模拟质量流量比在 0.09~0.39 范围内的基夫赛特炉熔炼过程。结果表明,4 个中央喷射分配喷嘴下方区域为高效反应区。增大中央氧流量可以改善颗粒与气体的混合状况,从而促进化学反应的进行,同时会缩短高效反应区;但是,由于喷嘴下颗粒柱的分散会使烟尘率增加。对于熔炼能力为 50000 kg/h 的基夫赛特炉,其最优的供氧方式为质量流量比取 0.31,在该工况下,炉料的化学反应可以充分进行,同时也保证较低的烟尘率。 展开更多
关键词 基夫赛特炉 中央喷射分散喷嘴 计算流体力学 中央氧 侧氧 最优化
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Platelet count combined with right liver volume and spleen volume measured by magnetic resonance imaging for identifying cirrhosis and esophageal varices 被引量:10
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作者 Xiao-Li Chen Tian-Wu Chen +7 位作者 Xiao-Ming Zhang Zhen-Lin Li Nan-Lin Zeng ping zhou Hang Li Jing Ren Guo-Hui Xu Jia-Ni Hu 《World Journal of Gastroenterology》 SCIE CAS 2015年第35期10184-10191,共8页
AIM: To determine whether the combination of platelet count(PLT) with spleen volume parameters and right liver volume(RV) measured by magnetic resonance imaging(MRI) could predict the Child-Pugh class of liver cirrhos... AIM: To determine whether the combination of platelet count(PLT) with spleen volume parameters and right liver volume(RV) measured by magnetic resonance imaging(MRI) could predict the Child-Pugh class of liver cirrhosis and esophageal varices(EV).METHODS: Two hundred and five cirrhotic patients with hepatitis B and 40 healthy volunteers underwent abdominal triphasic-enhancement MRI and laboratory examination of PLT in 109/L. Cirrhotic patients underwent endoscopy for detecting EV. Spleen maximal width(W), thickness(T) and length(L) in mm together with spleen volume(SV) and RV in mm3 were measured by MRI, and spleen volume index(SI) in mm3 was obtained by W × T × L. SV/PLT, SI/PLT and RV × PLT/SV(RVPS) were calculated and statistically analyzed to assess cirrhosis and EV.RESULTS: SV/PLT(r = 0.676) and SI/PLT(r = 0.707) increased, and PLT(r =-0.626) and RVPS(r =-0.802) decreased with the progress of Child-Pugh class(P < 0.001 for all). All parameters could determine the presence of cirrhosis, distinguish between each class of Child-Pugh class, and identify the presence of EV [the areas under the curve(AUCs) = 0.661-0.973]. A m o n g p a ra m e t e r s, R V P S c o u l d b e s t d e t e r m i n e presence and each class of cirrhosis with AUCs of 0.973 and 0.740-0.853, respectively; and SV/PLT could best identify EV with an AUC of 0.782.CONCLUSION: The combination of PLT with SV and RV could predict Child-Pugh class of liver cirrhosis and identify the presence of esophageal varices. 展开更多
关键词 CIRRHOSIS SPLEEN HEPATIC LOBE Magnetic resonance i
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基于端淬实验冷却曲线的相变潜热计算及其在镍基高温合金中的应用
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作者 赵天阳 付佩 +2 位作者 陈卓 周萍 李超 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第5期1718-1727,共10页
为了高效、低成本获取合金在不同冷却速率下的相变潜热,讨论基于端淬实验冷却曲线的牛顿热分析方法和改进牛顿热分析方法。通过对45^(#)钢相变潜热的计算验证这两种方法的有效性。结果表明,改进的牛顿热分析方法得到的相变潜热相对误差... 为了高效、低成本获取合金在不同冷却速率下的相变潜热,讨论基于端淬实验冷却曲线的牛顿热分析方法和改进牛顿热分析方法。通过对45^(#)钢相变潜热的计算验证这两种方法的有效性。结果表明,改进的牛顿热分析方法得到的相变潜热相对误差为5.20%,比牛顿热分析方法更准确。当冷却速率从50.15℃/min降低到33.40℃/min时,自制的CSU-A1粉末冶金镍基高温合金相变潜热释放量从4.3 J/g增加到12.29 J/g,这是因为当冷却速度较小时,合金组织有足够的时间完成相变过程。 展开更多
关键词 冷却曲线 端淬实验 牛顿热分析方法 相变潜热 镍基高温合金
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Blood perfusion of the contralateral testis evaluated with contrast-enhanced ultrasound in rabbits with unilateral testicular torsion 被引量:10
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作者 Lin Chen Wei-Wei Zhan +7 位作者 zhou-Jun Shen Wen-Bin Rui Chen Lv Man Chen Jian-Qiao zhou ping zhou Mi zhou Ying Zhu 《Asian Journal of Andrology》 SCIE CAS CSCD 2009年第2期253-260,共8页
The changes of blood perfusion of contralateral testis after unilateral testicular torsion remain controversial.In this study,28 New Zealand white male rabbits were randomly divided into five groups.Group A(n=8),the c... The changes of blood perfusion of contralateral testis after unilateral testicular torsion remain controversial.In this study,28 New Zealand white male rabbits were randomly divided into five groups.Group A(n=8),the control group,underwent a sham operation on the unilateral testis without inducing testicular torsion.In groups B,C,and D(n=5 each),unilateral testicular torsion was induced,and,after 3,6 or 24 h,respectively,detorsion was performed.In group E(n=5),permanent unilateral testicular torsion was applied.Contrast-enhanced ultrasound was used to observe the blood perfusion of the contralateral testis at the following stages:pre-torsion(preopration),immediately post-torsion(postopration),pre-detorsion,immediately post-detorsion,and late-stage post-detorsion(6-12 h post-detorsion in groups B-D)or at a similar time point(15-21 h post-torsion in group E).Time-intensity curves were generated,and the following parameters were derived and analyzed:arrival time,time to peak intensity,peak intensity,and half-time of the descending peak intensity.The analysis revealed that blood perfusion of the contralateral testis increased immediately after testicular torsion on the opposite side(P<0.05),which increased with prolonged testicular torsion of the other testis.This research demonstrated that contrast-enhanced ultrasound was valuable in evaluating blood perfusion of the contralateral testis after unilateral testicular torsion. 展开更多
关键词 contrast-enhanced ultrasound RABBITS testicular torsion
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Application of acoustic radiation force impulse imaging for the evaluation of focal liver lesion elasticity 被引量:11
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作者 ping Zhang ping zhou +3 位作者 Shuang-Ming Tian Ying Qian Jin Deng Lu Zhang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2013年第2期165-170,共6页
BACKGROUND: Acoustic radiation force impulse (ARFI) imaging is a new elastography method for the evaluation of tissue stiffness. This study aims to evaluate the performance of ARFI in noninvasive assessment of the tis... BACKGROUND: Acoustic radiation force impulse (ARFI) imaging is a new elastography method for the evaluation of tissue stiffness. This study aims to evaluate the performance of ARFI in noninvasive assessment of the tissue stiffness of focal liver lesion (FLL) and to explore its potential value in the differential diagnosis of FLL. METHODS: ARFI was performed in 140 patients with 154 FLLs, which included 28 hemangiomas (ANGIs), 14 focal nodular hyperplasias (FNHs), 61 hepatocellular carcinomas (HCCs), 39 metastases and 12 cholangiocellular carcinomas (CCCs). Virtual touch tissue quantification (VTTQ) values were obtained, analyzed and compared. The area under the receiver operating characteristic curve (AUROC) and optimal cut-off values were obtained using a receiver operating characteristic (ROC) curve analysis to assess diagnostic performance. All cases were definitively diagnosed using histopathology, CT, MRI or contrast-enhanced ultrasound. RESULTS: The VTTQ median values of ANGI, FNH, HCC metastasis and CCC were 1.30, 1.80, 2.52, 3.08 and 3.89 m/s respectively. A significant increase in the VTTQ values of different lesions was observed: ANGI【FNH【HCC【metastasis 【CCC (P【0.001). The AUROC (95% CI) of VTTQ values was 0.94 (0.90-0.98) for ANGI, 0.91 (0.87-0.96) for malignant lesions and 0.87 (0.79-0.94) for CCC. The sensitivity and specificity for ANGI (86.5%, 89.3%, respectively), malignancy (81.3% 92.9%, respectively), and CCC (91.7%, 72.5%, respectively) were associated with VTTQ cut-off values of 1.76, 2.22 and 3.00 m/s respectively.CONCLUSIONS: ARFI can accurately and objectively assess the elasticity of lesions by obtaining the shear wave elastic value of FLL with VTTQ. Therefore, ARFI is a novel, simple, noninvasive and useful diagnostic method for the characterization of FLL. 展开更多
关键词 acoustic radiation force impulse imaging elastosonography focal liver lesion
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