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Optimum Tilt Angle of Flow Guide in Steam Turbine Exhaust Hood Considering the Effect of Last Stage Flow Field

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 866-875页

作者： lihua cao Aqiang LIN Yong LI Bin XIAO School of Energy and Power Engineering Northeast Dianli UniversityJilin 132012China

Abstract Heat transfer and vacuum in condenser are influenced by the aerodynamic performance of steam tur- bine exhaust hood. The current research on exhaust hood is mainly focused on analyzing flow loss and optimal design of its structure without consideration of the wet steam condensing flow and the exhaust hood coupled with the front and rear parts. To better understand the aerodynamic performance influenced by the tilt angle of flow guide inside a diffuser, taking a 600 MW steam turbine as an example, a numerical simulator CFX is adopted to solve compressible three-dimensional （3D） Reynolds time-aver- aged N-S equations and standard k-e turbulence model. And the exhaust hood flow field influenced by different tilt angles of flow guide is investigated with consideration of the wet steam condensing flow and the exhaust hood coupled with the last stage blades and the condenser throat. The result shows that the total pressure loss coefficient and the static pressure recovery coefficient of exhaust hood change regularly and monotonously with the gradual increase of tilt angle of flow guide. When the tilt angle of flow guide is within the range of 30~ to 40~, the static pressure recovery coefficient is in the range of 15.27% to 17.03% and the total pressure loss coefficient drops to approximately 51%, the aerodynamic performance of exhaust hood is significantly improved. And the effectiveenthalpy drop in steam turbine increases by 0.228% to 0.274%. It is feasible to obtain a reasonable title angle of flow guide by the method of coupling the last stage and the condenser throat to exhaust hood in combination of the wet steam model, which provides a practical guidance to flow guide transformation and optimal design in exhaust hood.

关键词： Steam turbine Exhaust hood Last stageblades Tilt angle of flow guide Aerodynamicperformance

Application of the Static Headland-Bay Beach Concept to a Sandy Beach: A New Elliptical Model

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Journal of Ocean University of China 2020年第1期19卷 81-89页

作者： LI Bing ZHUANG Zhenye cao lihua DU Fengchao College of Marine Geosciences Ocean University of ChinaQingdao 266100China Island Research Center Ministry of Natural ResourcesPingtan 350400China Key Laboratory of Submarine Science and Exploration Technology Education Ministry of ChinaQingdao 266100China Shandong Marine Resources and Environment Institute Shandong Provincial Key Laboratory of Restoration for Marine EcologyYantai 264006China

The headland-bay beach is one of the most common coastal types in the *** morphology reflects the changes that occurred during long-term evolution of the sandy *** headland-bay beach models have been proposed to simulate the coastline’s configuration in *** this paper,a new elliptical model is proposed,described,and *** the east coast of Laizhou Bay in Shandong Province from Longkou Port to Diaolongzui,four typical headland-bay beaches have developed,and four headland-bay beach models are used in this paper to simulate the morphology of these beaches to assess the applicability of each *** simulation results of the elliptical model verify that it is applicable to the study *** addition,the elliptical model is easy to *** simulation and field investigations,we concluded that most of the coastal segments in this area will remain in an erosion state,and the human activity has a significant impact on the shoreline’s evolution.

关键词： static headland-bay beach concept elliptical model sandy beach coastal erosion east coast of Laizhou Bay

TXV Technology:The cornerstone of 3D system-in-packaging

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Science China(Technological Sciences) 2022年第9期65卷 2031-2050页

作者： ZHAO HeRan CHEN MingXiang PENG Yang WANG Qing KANG Min cao lihua School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China The 47th Institute of China Electronics Technology Group Corporation Shenyang 110000China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Shenyang National Laboratory for Materials Science Shenyang 110016China

System-in-packaging(Si P) can realize the integration and miniaturization of electronic devices and it is significant to continue Moore’s ***-X-via(TXV) technology is the cornerstone of 3 D-SiP,which enables the vertical stacking and electrical interconnection of electronic *** originated from through-hole(TH) in PCB substrates and evolved in different substrate materials,such as silicon,glass,ceramic,and *** work provides a comprehensive review of four distinguishing TXV technologies(through silicon via(TSV),through glass via(TGV),through ceramic via(TCV),and through mold via(TMV)),including the fabrication mechanisms,processes,and *** TXV technology has unique characteristics and owns particular processes and *** process methods,key technologies,application fields,and advantages and disadvantages of each TXV technology were *** cutting-edge through-hole process and development direction were reviewed.

关键词： through silicon via(TSV) through ceramic via(TCV) through glass via(TGV) through mold via(TMV) 3D packaging chip stacking interposer

Variations in EXD3 caused congenital cataracts in three Chinese families

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Genes & Diseases 2023年第3期10卷 660-663页

作者： lihua cao Yunji Leng Xinmiao Nie Shuyang Zhao Tianxiao Zhang College of Kinesiology Shenyang Sport UniversityShenyangLiaoning 110102China The Research Center for Medical Genomics China Medical UniversityShenyangLiaoning 110122China Department of Ophthalmology The Fourth Affiliated Hospital of China Medical UniversityKey Laboratory of Lens Research Liaoning ProvinceEye Hospital of China Medical UniversityShenyangLiaoning 110033China

Congenital cataract is a clinically and genetically heterogeneous disease characterized by any opacity of the lens presenting at birth or in the first year of life,with an incidence of 1–6/10,000 live births in developed countries and 5–15/10,000 live births in developing *** cataract accounts for 7.4%–15.5%of all childhood blindness,and it occurs as either a syndromic disease or an isolated(nonsyndromic)disease with or without other ocular malformations,such as microcornea.

关键词： birth cataract incidence

Distribution characteristics of soil organic carbon and nitrogen in farmland and adjacent natural grassland in Tibet

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International Journal of Agricultural and Biological Engineering 2016年第1期9卷 135-145页

作者： Liu Heman cao lihua Xu Changchang Yang Hong Li Baoguo College of Resources and Environment China Agricultural UniversityBeijing 100093China Research Center of Climate Change and Material Cycle of Pedosphere of Tibet Pleateau Agricultural and Animal Husbandry CollegeTibet UniversityLinzhi 860000China

Land-use significantly affects soil organic carbon(SOC)and nitrogen cycling,eventually leading to global climate *** cold and arid climate conditions in Tibet are not conducive to transformation of SOC and ***,research on SOC and nitrogen distribution under different land-use patterns in Tibet is an important basis to assess the soil carbon and nitrogen potential in the land ecosystem of this *** study aims to explain the effects of two land-use patterns,namely,farmland and grassland,on SOC and nitrogen contents in the cold regions of *** study also seeks to provide a scientific basis for the agricultural and grass production *** achieve these goals,the changing features of total nitrogen(TN),mineralized nitrogen(nitrate nitrogen(NN)and ammonium nitrogen(AN)),and SOC were analyzed in different soil depths(0-5,5-10,10-20,20-30,30-40,and 40-50 cm)in farmland and adjacent natural *** differences in carbon and nitrogen contents between the farmland and grassland of the main agricultural area of Tibet were determined through combined field survey and lab *** showed that the contents of SOC,TN and mineralized nitrogen in the grassland and farmland decreased with increasing soil depth mainly in the surface with depth of 0-20 *** effects of the different land-use patterns on the contents of SOC and TN were primarily evident in the 0-10 cm surface *** contents of SOC and TN in the farmland were significantly lower than those in the grassland,with mean reduction by 28.36%for SOC and 20.76%for *** the soil layer is deeper than 10 cm,the contents of SOC and TN in the farmland were greater than those in the *** finding indicated that the transformation from grassland to farmland in Tibet mainly influenced the SOC and TN in the 0-10 cm surface ***,the results showed that the increment of carbon in the deep soil layers of the farmland partially offsets the SOC loss from the surface becau

关键词： Tibet farmland grassland soil organic carbon soil total nitrogen nitrate nitrogen ammonium nitrogen

Ginkgo paste improves tinea corporis in a guinea pig model

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BIOCELL 2020年第4期44卷 649-653页

作者： lihua cao MINGSAN MIAO YAN ZHENG HUIYAUN HUANG RUI ZHANG DANDAN LIU Academy of Chinese Medical Sciences Henan University of Chinese MedicineZhengzhou450046China Department of Pharmacology Henan University of Chinese MedicineZhengzhou450046China

To investigate the effects of Ginkgo paste for external use on tinea corporis in a guinea pig *** guinea pig tinea corporis model were induced by infection with Trichophyton mentagrophytes *** then,high and low doses of Ginkgo water-paste and alcohol-paste were administrated to the *** symptom,tinea corporis skin lesions and histopathological aspects of guinea pig were *** and low doses of Ginkgo alcohol-paste and Ginkgo water-paste could significantly reduced the tinea corporis symptom(P<0.01),increased negative rate of strain culture(P<0.01),and improved pathological changes of tinea corporis(P<0.01).The best efficacy was observed in high dose ginkgo alcohol paste *** results suggest that Ginkgo paste exhibits the efficacy to treat tinea corporis in a guinea pig model.

关键词： Ginkgo Alcohol paste Tinea corporis Guinea pig

A Retrospective Study of Treatment Efficacy of 65 Children with Ametroic Amblyopia

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Eye Science 2012年第2期27卷 85-88页

作者： Yuxiang Zhang lihua Huang Changyang cao Yingfang Li Shaoguan Hygienic Hospital of Women and Children Shaoguan 512026 China

Purpose: To investigate relationship between treatment efficacy and the severity of ametropic amblyopia, the type of anisometropia and patient age. Methods:A total of 65 children with ametropic amblyopia undergoing clinical treatment in the ophthalmology department of Shaoguan Hygienic Hospital of Women and Children between June 2005 and November 2011 were enrolled in this study. The treatment efficacy for those subjects with different severities of ametropic amblyopia, types of anisometropia and ages was recorded. Results: The near-recovery/recovery rate, improvement rate and ineffectiveness rate were 70.8%, 16.9% and 12.3%, respectively. The recovery rates in mild-, moderate- and severe amblyopia groups were 97.1%, 61.1% and 8.3% respectively (P0.05), whereas a statistically significant difference was noted between myopic children compared with their hyperopic and myopic-anisometropia counterparts (all P<0.05). The recovery rate for patients aged 3 to 6 years was 86.8% and 48.1% for those aged between 7 and 10 years (P<0.05). Conclusion: The treatment efficacy in ametropic amblyopia is associated with the severity of amblyopia, type of anisometropia and patient's age. Older patients with more severe amblyopia had poorer treatment efficacy. The efficacy in patients with hyperopic and astigmatic anisometropia was better than that for myopic anisometropia subjects.

关键词：治疗功效弱视儿童治疗效果临床治疗严重程度恢复率回收率

Characterization of natural fiber from manau rattan(Calamus manan)as a potential reinforcement for polymer-based composites

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Journal of Bioresources and Bioproducts 2022年第3期7卷 190-200页

作者： Linhu Ding Xiaoshuai Han lihua cao Yiming Chen Zhe Ling Jingquan Han Shuijian He Shaohua Jiang Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Chemical EngineeringNanjing Forestry UniversityNanjing 210037China

Researches on novel natural fibers in polymer-based composites will help promote the invention of novel reinforcement and expand their possible ***,in this study,novel cellulosic fibers were extracted from the stem of manau rattan(Calamus manan)by mechanical *** chemical,thermal,mechanical and morphological properties of manau rattan fibers were comprehensively analyzed and studied by Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD)analysis,thermogravimetric analysis(TGA),single fiber tensile test and scanning electron microscopy(SEM).Component analysis re-sults showed that the cellulose,hemicellulose and lignin contents of *** fibers were 42wt%,20wt%,and 27wt%,*** surface of the rattan fiber was hydrophilic according to the oxygen/carbon ratio of *** *** has a crystalline index of 48.28%,inducing a max-imum degradation temperature of 332.8°*** reveals that it can be used as a reinforcement for thermoplastic composites whose operating temperature is below 300°*** average ten-sile strength can reach(273.28±52.88)MPa,which is beneficial to improve the mechanical properties of rattan fiber reinforced *** SEM images displayed the rough surface of the fiber,which helped to enhance the interfacial adhesion between the fibers and matrices in *** results indicate the great potential of *** fibers as the reinforcement in polymer-based composites.

关键词： Cellulose Manau rattan(Calamus manan) Mechanical properties Natural fiber Thermal analysis

Collective stimulated Brillouin scattering modes of two crossing laser beams with shared scattered wave

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Matter and Radiation at Extremes 2021年第6期6卷 45-55页

作者： Jie Qiu Liang Hao lihua cao Shiyang Zou Institute of Applied Physics and Computational Mathematics Beijing 100094China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China

In inertial confinement fusion(ICF),overlapping of laser beams is *** to the effective high laser intensity of the overlapped beams,the collective mode of stimulated Brillouin scattering(SBS)with a shared scattered light wave is potentially *** this work,an exact analytic solution for the convective gain coefficient of the collective SBS modes with shared scattered wave is presented for two overlapped beams based on a linear *** effects of the crossing angle,polarization states,and finite beamoverlapping volume of the two laser beams on the shared light modes are analyzed for cases with zero and nonzero wavelength difference between the two *** is found that all these factors have a significant influence on the shared lightmodes of ***,the out-of-plane modes,in which the wavevectors of daughter waves lie in different planes from the two overlapped beams,are found to be important for certain polarization states and especially for obtuse crossing *** particular,adjusting the polarization directions of the two beams to be orthogonal to each other or tuning the wavelength difference to a sufficiently large value(of the order of nanometers)are found to be effective methods to suppress the shared light modes of *** work will be helpful for comprehending and suppressing collective SBS with shared scattered waves in ICF experiments.

关键词： polarization scattering tuning