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Chapter 3 Extra-galactic gamma-ray sources

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Chinese Physics C 2022年第3期46卷 63-84页

作者： xiang-Yu Wang Xiao-Jun Bi Zhen cao Piero Vallania Han-rong Wu Da-Hai Yan Qiang Yuan School of Astronomy and Space Sciences Nanjing UniversityNanjing 210093China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China INAF-Osservatorio Astrofisico di Torino Strada Osservatorio 2010025 Pino Torinese(TO)Italy and INFN Sezione di TorinoVia P.Giuria 110125 TorinoItaly Key Laboratory for the Structure and Evolution of Celestial Objects Yunnan ObservatoriesChinese Academy of SciencesKunming 650011China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China

Extra-galactic gammaray sources,such as gamma-ray bursts,active galactic nuclei,starburst galaxies,are interesting and important targets for LHAASO *** this chapter,the prospects of detecting these sources with LHAASO and their physical implications are *** upgrade plan for the Water Cherenkov Detector Array(WCDA),which aims to enhance the detectability of relatively lower energy photons,is also *** addition,a study on constraining the extragalactic background light with LHAASO observation of blazars is presented.

关键词： AGN Gamma-rays GRBs

Long-term effect of vasectomy on spermatogenesis in ,en： a morphometric study

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Asian Journal of Andrology 2013年第3期15卷 434-436页

作者： Yu xiang Peng Luo Yun cao Zheng-Wei Yang Morphometric Research Laboratory North Sichuan Medical College Nanchong 637007 China Department of Surgery People's Hospital of Peng'an County Nanchong 638250 China

Spermatogenic damage may occur after vasectomy, and the damage is pressure mediated, occurring when the occluded reproductive tract is unable to accommodate additional sperm produced by the testis. This study aimed to determine the long-term effect of vasectomy on spermatogenesis in humans and clarify how the balance between sperm production in the testis and sperm storage in or removal from the tract might be maintained. During inguinal hernia repair, an open biopsy was performed to obtain testicular tissue blocks from 51 Chinese men （aged ≥ 50 years）, of whom 25 （control group） had not undergone vasectomy and 26 （vasectomized group） had undergone bilateral vasectomy 22-42 years before. Methacrylate resin-embedded testicular sections were made, and morphometric studies were performed using light microscopy. In addition, sizes of the testis and epididymis were estimated with ultrasonography. The testicular tissue blocks obtained from one control and seven vasectomized men consisted almost completely of connective tissue. In the other 43 men, significant differences were not found between the two groups in the testicular or epididymal size, qualitative histology or quantitative parameters including the mean diameter or volume fraction of the seminiferous tubules. In conclusion, sperm production and sperm storage/removal reached a static equilibrium after vasectomy, likely due to spermatogenic degeneration or less sperm production as a result of aging or due to vasectomy-induced testicular （interstitial） fibrosis. Thus, complications that might occur in association with overproduction of sperm and distension of the tract would disappear or be relieved with time.

关键词： histology humans morphometry spermatogenesis testis vasectomy

Effect of Nitrate on Activities and Transcript Levels of Nitrate Reductase and Glutamine Synthetase in Rice

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Pedosphere 2008年第5期18卷 664-673页

作者： cao Yun FAN Xiao-rong SUN Shu-Bin XU Guo-Hua HU Jiang SHEN Qi-rong College of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China）.

Real-time polymerase chain reaction analysis was used to compare the effect of NO3^- on the activities of nitrate reductase （NR） and glutamine synthetase （GS）, and the transcript levels of two NR genes, OsNial and OsNia2, two cytosolic GS1 genes, OsGln1;1 and OsGln1;2, and one plastid GS2 gene OsGln2, in two rice （Oryza sativa L.） cultivars Nanguang （NG） and Yunjing （Y J）. Both cultivars achieved greater biomass and higher total N concentration when grown in a mixed N supply than in sole NH4^＋ nutrition. Supply of NO3^- increased NR activity in both leaves and roots. Expression of both NR genes was also substantially enhanced and transcript levels of OsNia2 were significantly higher than those of OsNial. NO3 also caused an increase in GS activity, but had a complex effect on the expression of the three GS genes. In roots, the OsGln1;1 transcript increased, but OsGln1;2 decreased. In leaves, NO3^- had no effect on the GS1 expression, but the transcript for OsGln2 increased both in the leaves and roots of rice with a mixed supply of N. These results suggested that the increase in GS activity might be a result of the complicated regulation of the various GS genes. In addition, the NO3-induced increase of biomass, NR activity, GS activity, and the transcript levels of NR and GS genes were proportionally higher in NG than in Y J, indicating a stronger response of NG to NO3^- nutrition than YJ.

关键词： ammonium glutamine synthetase nitrate nitrate reductase Oryza sativa L.

Study on Phase Equilibrium Properties for CO_(2)^+ Cosolvent Binary Systems

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Chinese Chemical Letters 2001年第9期12卷 829-832页

作者： Zhang Jing CHANG Wu xiang YANG cao Wei LIANG Faculty of Science Beijing University of Chemical TechnologyBeijing 100029

In this study, the constant volume, visual method is used to measure the critical point of CO2+toluene, CO2+cyclohexane, CO2+n-butyraldehyde, CO2+i-butyraldehyde, CO2+methanol and CO2+alcohol binary systems. The relationship between critical point and the concentration of the entrainer for different substances has been discussed, and the comparison of the phase behavior of single component system and that of binary systems have been carried out.

关键词： Critical point supercritical binary system phase equilibrium

Effect of Solution-ECAP-Aging Treatment on the Microstructure and Properties of TB8 Titanium Alloy

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Journal of Wuhan University of Technology(Materials Science) 2023年第3期38卷 669-676页

作者：陈枫华许晓静 LIU Yangguang HU Chaoxing cao Bin BAI xiang Institute for Advanced Manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang 212013China

The microstructure and mechanical properties of the TB8 titanium alloy were controlled by a secondary processing technology of solution-equal channel angular pressing(ECAP)-aging treatment,which combined strong plastic deformation with heat treatment. The effects of ECAP and heat treatment on the microstructure and properties of the titanium alloy were systematically investigated by optical microscopy(OM), scanning electron microscopy(SEM), hardness tests, and tensile property analysis. The results indicate that the metallographic structure without ECAP treatment is mainly equiaxed β-phase, while that after ECAP treatment is equiaxed β-phase with grain fragmentation, slip bands, and new small grains. After 850 ℃ solutionECAP-520 ℃ aging treatment, the titanium alloy has the smallest grain size, while the directionality of tissue growth along the ECAP direction is the most apparent. Under the same solution-aging conditions, the hardness of the titanium alloy increases from 431.5 to 531.2 HV compared to that without ECAP treatment, i e, increases by 23.11%, and the tensile strength increases from 1 045.30 to 1 176.25 MPa, i e, increases by 12.5%.

关键词： equal channel angular pressing heat treatment TB8 titanium alloys microstructure mechanical properties

Primary intestinal lymphangiectasia presenting as limb convulsions:A case report

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World Journal of Clinical Cases 2022年第18期10卷 6234-6240页

作者： Yun cao Xiao-Hong Feng Hai-xiang Ni Department of Endocrinology The First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Traditional Chinese Medicine)Hangzhou 310006Zhejiang ProvinceChina

BACKGROUND Primary intestinal lymphangiectasia(PIL)is a rare protein-losing enteropathy characterized by abnormally dilated lymphatic structures,resulting in leakage of lymph(rich in protein,lymphocytes,and fat)from the intestinal mucosal and submucosal layers and thus hypoproteinemia,lymphopenia,hypolipidemia,and pleural *** SUMMARY A 19-year-old Chinese male patient complained of recurrent limb convulsions for the last 1 *** investigations revealed low levels of calcium and magnesium along with hypoproteinemia and high parathyroid hormone levels,whereas gastroscopy exhibited chronic non-atrophic gastritis and duodenal lymphatic *** gastric biopsy showed moderate chronic inflammatory cell infiltration distributed around a small mucosal patch in the descending duodenum followed by lymphatic dilatation in the mucosal lamina propria,which was later diagnosed as *** following appropriate mediumchain triglycerides nutritional support significantly improved the patient’s *** Since several diseases mimic the clinical symptoms displayed by PIL,like limb convulsions,low calcium and magnesium,and loss of plasma proteins,it is imperative to conduct a detailed analysis to avoid any misdiagnosis while pinpointing the correct clinical diagnosis and simultaneously ruling out other clinical aspects in the reported cases without any past disease history.A careful assessment should always be made to ensure an accurate diagnosis in a timely manner so that the patient can be delivered quality health services for a positive health outcome.

关键词： Protein-losing enteropathy Primary intestinal lymphangiectasia Limb convulsions Adult Case report

Determination of boron concentration in uranium fuel samples by ICP-OES following a separation step by cation exchange resin

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Nuclear Science and Techniques 2018年第3期29卷 165-171页

作者： Yan Luo Hai-Xia Cong rong-rong Cui Chang-Qing cao Wei Zhou Zhong-Qi Zhao Shanghai Institute of Applied Physics Chinese Academy of Sciences

The boron content of uranium fuel samples with boron concentrations in the range of 0.05–10 μg/g was determined using inductively coupled plasma optical emission spectrometry(ICP-OES) after the uranium was separated by cation exchange. The samples were dissolved in 3 M HNO_3 on a hot plate at 150℃ and evaporated to near dryness. The residues were redissolved in 0.2 M HNO-_3 and passed through a column loaded with Dowex 50WX8-400 resin. Uranium was adsorbed on the resin,while boron was easily eluted with 0.2 M HNO_3. The boron content of the effluent was determined using ICPOES. Several strategies were employed to improve the reliability of the experimentally determined boron *** addition of mannitol and proper control of the evaporation process were shown to be effective in preventing boron loss during sample dissolution and evaporation. The memory effect was eliminated by flushing the system with 1.5% ammonia for 30 s between successive sample runs,and the matrix match method was used to eliminate the matrix effect arising from mannitol during the ICP-OES analysis. The accuracy of the results of the analysis was determined by addition recovery tests and by comparison with the results of three Chinese certified reference materials(GBW04242, GBW04243, and GBW04232). Using the method we developed, the limit of detection for boron was as low as 0.05 μg/g in uranium fuel samples, and the relative standard deviations for 0.1–0.5 g uranium samples with 0.05–2 μg/g of boron were within 9%.

关键词： Boron determination ICP-OES Boron evaporation Memory effect Matrix match method Resin separation

Schedule refinement for homogeneous multi-core processors in the presence of manufacturing-caused heterogeneity

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Frontiers of Information Technology & Electronic Engineering 2015年第12期16卷 1018-1033页

作者： Zhi-xiang CHEN Zhao-lin LI Shan cao Fang WANG Jie ZHOU Department of Automation Tsinghua University Institute of Microelectronics Tsinghua University Research Institute of Information Technology Tsinghua University Tsinghua National Laboratory for Information Science and Technology Tsinghua University The School of Information and Electronics Beijing Institute of Technology

Multi-core homogeneous processors have been widely used to deal with computation-intensive embedded applications. However, with the continuous down scaling of CMOS technology, within-die variations in the manufacturing process lead to a significant spread in the operating speeds of cores within homogeneous multi-core processors. Task scheduling approaches, which do not consider such heterogeneity caused by within-die variations,can lead to an overly pessimistic result in terms of performance. To realize an optimal performance according to the actual maximum clock frequencies at which cores can run, we present a heterogeneity-aware schedule refining(HASR) scheme by fully exploiting the heterogeneities of homogeneous multi-core processors in embedded *** analyze and show how the actual maximum frequencies of cores are used to guide the scheduling. In the scheme,representative chip operating points are selected and the corresponding optimal schedules are generated as candidate schedules. During the booting of each chip, according to the actual maximum clock frequencies of cores, one of the candidate schedules is bound to the chip to maximize the performance. A set of applications are designed to evaluate the proposed scheme. Experimental results show that the proposed scheme can improve the performance by an average value of 22.2%, compared with the baseline schedule based on the worst case timing analysis. Compared with the conventional task scheduling approach based on the actual maximum clock frequencies, the proposed scheme also improves the performance by up to 12%.

关键词： Schedule refining Multi-core processor Heterogeneity Representative chip operating point

Bulk Heterojunction Photovoltaic Devices Based on a Poly(2-Methoxy,5-Octoxy)-1,4-Phenylenevinylene-Single Walled Carbon Nanotube-ZnSe Quantum Dots Active Layer

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Chinese Physics Letters 2013年第10期30卷 187-190页

作者： QU Jun-rong ZHENG Jian-Bang WU Guang-rong cao Chong-De Department of Applied Physics School of ScienceNorthwestern Polytechnical UniversityXi'an 710072

A solution-processed bulk heterojunction photovoltaic cell is fabricated based on poly[(2-methoxy,5-octoxy)-1,4-phenylenevinylene](MOPPV)-single walled carbon nanotube(SWNT)-ZnSe quantum *** surface morphology shows the formation of an interpenetrating network between well-dispersed SWNTs and ZnSe in the MOPPV matrix.A blue-shifted absorption band indicates the strong electron interaction between SWNTs,ZnSe and MOPPV.A marked increase in the short-circuit current and power conversion efficiency(PCE)of ITO/PEDOT:PSS/MOPPV-SWNT-ZnSe/LiF/Al devices was achieved and compared with that without *** indicate that the enhanced performance is contributed by a high photocurrent due to efficient exciton dissociation and increased mobility for carrier transport in the SWNT pathway.

关键词： ZnSe Active Carbon