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贵州麻江地区寒武纪杷榔动物群的群落组成和生态空间分析

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古生物学报 2024年第2期63卷 233-245页

作者：马闻语陈圣光罗绣春王德智杨宇宁贵州大学资源与环境工程学院喀斯特地质资源与环境教育部重点实验室贵阳550025

寒武纪特异埋藏化石库保存了海洋生物群落最原始的生态结构,为群落生态研究提供了宝贵材料。贵州寒武纪斜坡相区的杷榔动物群(第4期)具有较高的生物多样性,但定量生态学研究相对薄弱。本研究对贵州麻江地区杷榔动物群的新产地平定剖面... 详细信息

寒武纪特异埋藏化石库保存了海洋生物群落最原始的生态结构,为群落生态研究提供了宝贵材料。贵州寒武纪斜坡相区的杷榔动物群(第4期)具有较高的生物多样性,但定量生态学研究相对薄弱。本研究对贵州麻江地区杷榔动物群的新产地平定剖面进行化石采集和分类统计,并运用多元数理统计方法开展定量化分析。鉴定出腕足动物、海绵动物、刺胞动物、节肢动物、软舌螺动物、古虫动物、开腔骨动物和曳鳃动物8个化石门类,计31属33种,划分出12种生态类型。其中,腕足动物具有最高的个体丰度(占比61.5%),节肢动物物种分异度最高(占比60%),群落以底栖固着生态类型为主,游泳捕食为辅。对比分析结果显示,寒武纪海洋群落具有空间异质性,且节肢动物在影响群落组成和生态空间利用上起决定性作用。随水体深度增加,海洋生态群落中的表栖类群出现明显扩张,也体现了环境对群落面貌的塑造作用。

关键词：寒武纪杷榔动物群群落组成生态空间华南

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Acro-dermato-ungual-lacrimal-tooth syndrome:case report

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Chinese Medical Journal 2007年第9期120卷 851-853页

作者： YANG Jian ZHANG Hong-juan YANG Wen-lin chen guang-sheng TANG Zhi-wei chen Shuang YE Wen-hong Department of Dermatology Second Affiliated Hospital of Guangzhou Medical College Guangzhou 510260 China Department of Stomatology Second Affiliated Hospital of Guangzhou Medical College Guangzhou 510260 China Department of Radiology Second Affiliated Hospital of Guangzhou Medical College Guangzhou 510260 China Department of Medical Genetics and Cell Biology Guangzhou Medical College Guangzhou 510180 China

Acro-dermato-ungual-lacrimal-tooth syndrome （ADULT syndrome, OMIM 103285） is a rarely seen ectodermal dysplasia disorder first described by Propping and Zerres in 1993. ADULT syndrome is known as an autosomal dominant disorder. Only a family constellation and four independent cases were reported worldwide up to now. Here, we report a case of ADULT syndrome, which is the first case reported from China.

关键词： acro-dermato-ungual-lacrimal-tooth (ADULT) syndrome ectodermal dysplasia abnormalities, congenital

Soil Inorganic Nitrogen and Microbial Biomass Carbon and Nitrogen Under Pine Plantations in Zhanggutai Sandy Soil

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Pedosphere 2008年第6期18卷 775-784页

作者： YU Zhan-Yuan chen Fu-sheng ZENG De-Hui ZHAO Qiong chen guang-sheng Daqinggou Ecological Station Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China）. Life College Nanchang University Nanchang 330029 （China） Ecosystem Sciences and Regional Analysis （ESRA） Lab. School of Forestry ＆Wildlife Science Auburn University Alabama 36849 （USA）

The dynamics of soil inorganic nitrogen （NH4^＋ -N and NO3^- -N） and microbial biomass carbon （Cmic） and nitrogen （Nmic） under 30-year-old fenced Pinus sylvestris L. var. mongolica Litvin （SF）, unfenced P. sylvestris L. var. mongolica Litvin （SUF）, and unfenced Pinus densiflora Siebold et Zucc. （DUF） plantations in the Zhanggutai sandy soil of China were studied during Apr. to Oct. 2004 by the in situ closed-top core incubation method. All mentioned C and N indices in each stand type fluctuated over time. The ranges of inorganic N, Cmic, and Nmic contents in the three stand types were 0.7-2.6, 40.0-128.9, and 5.4-15.2 μg g^-1, respectively. The average contents of soil NH4^＋ -N and Cmic under the three 30-year-old pine plantations were not different. However, soil NO3^ -N and total inorganic N contents decreased in the order of SUF ≥ SF ≥ DUF, the Nmic content was in the order of SF = SUF 〉 DUF, and the Cmic：Nmic ratio was in the order of SUF = DUF 〉 SF. Seasonal variations were observed in soil inorganic N, microbial biomass, and plant growth. These seasonal variations had certain correlations with microbe and plant N use in the soil, and their competition for NH4^＋ -N was mostly regulated by soil N availability. The influence of tree species on inorganic N and Nmic were mainly because of differences in litter quality. Lack of gazing decreased the Cmic：Nmic ratio owing to decreased carbon output and increased the ability of soil to supply N. The soil N supply under the P. sylvestris var. mongolica plantation was lower than under the P. densiflora plantation.

关键词： ecosystem management Horqin sandy land soil nitrogen availability Pinus densiflora Pinus sylvestris vat. mongoliea

Soil animals and nitrogen mineralization under sand-fixation plantations in Zhanggutai region,China

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Journal of Forestry Research 2007年第1期18卷 73-77页

作者： chen Fu-sheng ZENG De-hui HU Xiao-fei chen guang-sheng YU Zhan-yuan Daqinggou Ecological Station Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 P. R. China College of Life Sciences Nanchang University Nanchang 330031 P. R. China Ecosystem Sciences ＆ Regional Analysis Laboratory School of Forestry and Wildlife Sciences Auburn University AL 36830 USA

The effects of soil animals on soil nitrogen (N) mineralization and its availability were studied by investigating soil animal groups and their amounts of macro-faunas sorted by hand, and middle and microfaunas distinguished with Tullgren and Baermann methods under three Pinus sylvestris var. mongolica Litv. plantations in Zhanggutai sandy land, China. In addition, soil N mineralization rate was also measured with PVC closed-top tube in situ incubation method. The soil animals collected during growing season belonged to 13 orders, 5 groups, 4 phyla, whose average density was 86 249.17 individuals·m^(-2). There were significant differences in soil animal species, densities, diversities and evenness among three plantations. Permanent grazing resulted in decrease of soil animal species and diversity. The average ammonification, nitrification and mineralization rates were 0.48 g·m^(-2)·a^(-1), 3.68 g·m^(-2)·a^(-1) and 4.16 g·m^(-2)·a^(-1), respectively. The ammonification rate in near-mature forest was higher than that in middle-age forests, while the order of nitrification and net mineralization rates was: middle-age forest without grazing < middle-age forest with grazing < near-mature forest with grazing (P<0.05). Soil N mineralization rate increased with soil animal amounts, but no significant relationship with diversity. The contribution of soil animals to N mineralization was different for different ecosystems due to influences of complex factors including grazing, soil characteristics, the quality and amount of litter on N mineralization.

关键词： Soil animals N mineralization Pinus sylvestris var. mongolica Litv. Zhanggutai sandy land

Energy saving analysis for CO_(2)–O_(2)mixed injection technology in converter steelmaking

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Journal of Iron and Steel Research International 2024年第5期31卷 1095-1103页

作者： Bao-chen Han Chun-liang Gao Ya-qiang Li Dan Liu guang-sheng Wei Rong Zhu Hebei Key Laboratory of Material Near-Net Forming Technology School of Material Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018HebeiChina Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai054000HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Energy-saving in China's iron and steel industry still relies on the development and improvement of short-term energy saving ***,a special converter smelting technology incorporating energy saving was *** evaluate the energy-saving potential of the CO_(2)–O_(2)mixed injection(COMI)technology,collected production data were used to develop an improved techno-economic *** reveal that the technology can save energy through auxiliary material consumption,sensible heat of solid by-product,iron loss reduction,and energy *** application of COMI technology in an enterprise is cost effective,involving the energy saving potential of 0.206 GJ/t,the cost of conserved energy of−48.83 yuan/GJ,and a simple payback period of 0.35 year for a 60-million-yuan *** analysis shows that the investment cost and discount rate primarily influence the cost of conserved energy of the *** the discount rate increased,the cost of conserved energy also gradually ***,the COMI technology is an energy-saving technology with good development prospects.

关键词： Converter steelmaking COMI technology Energy saving Techno-economic model Investment cost

Effects of soil moisture and soil depth on nitrogen mineralization process under Mongolian pine plantations in Zhanggutai sandy land, P. R. China

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Journal of Forestry Research 2005年第2期16卷 101-104页

作者： chenFu-sheng ZENGDe-hui SINGHAnandNarain chenguang-sheng DaqinggouEcologicalStation InstituteofAppliedEcologyChineseAcademyofSciencesShenyang110016P.R.China DaqinggouEcologicalStation InstituteofAppliedEcologyChineseAcademyofSciencesShenyang110016P.R.China／／GraduateSchoolofChineseAcademyofSciencesBeijing100039PR.China DaqinggouEcologicalStation InstituteofAppliedEcologyChineseAcademyofSciencesShenyang110016P.R.China／／SchoolofForestryandWddlifeSciencesAuburnUniversityAL36830U.S.A

The rates of soil N mineralization at soil depths of 0-15, 15-30, 30-45 and45-60 cm and moisture regimes were measured at three sand-fixation plantations of Pinus sylvestrisvar. mongolica by laboratory aerobic incubation method. The results showed that average rates ofsoil net N-mineralization across soil depth varied from 1.06 to 7.52 mg · kg^(-1)·month^(-1) atsoil depths from 0 to 60 cm. Statistical analyses indicated that the effects of different soildepths, moistures and their interactions on net N-mineralization rates were significant (P < 0.05).The net N-mineralization rates significantly decreased with increasing soil depths and at depth 0-15cm accounted for 60.52% of that at depth of 0-60 cm. There was no difference in soil netN-mineralization rates between half and fully-saturated water treatments, however these rates weresubstantially higher than that without water treatment (P < 0.05). The factors influencing Nmineralization process have to be studied further in these semiarid pine ecosystems.

关键词： laboratory aerobic incubation method nitrogen mineralization managementpractices sand-fixation forest semiarid region pinus sylvestris var· mongolica soil depth

Applying deep learning technique to chiral magnetic wave search

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Chinese Physics C 2024年第8期48卷 170-176页

作者： Yuan-sheng Zhao Xu-guang Huang Physics Department and Center for Particle Physics and Field Theory Fudan UniversityShanghai 200433China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics National Natural Science Foundation of China and Fudan UniversityShanghai 200438China

The chiral magnetic wave(CMW)is a collective mode in quark-gluon plasma originated from the chiral magnetic effect(CME)and chiral separation *** detection in heavy-ion collisions is challenging owing to significant background ***[*** et al.,***.C 106,L051901(2022)],we constructed a neural network that accurately identifies the CME-related signal from the final-state pion *** this study,we have generalized this neural network to the case of CMW *** show that,after an updated training,the neural network effectively recognizes the CMW-related ***,we have assessed the performance of the neural network in comparison with other known methods for CMW search.

关键词： deep learning chiral magnetic wave relativistic heavy-ion collisions

Volume of fluid simulation of single argon bubble dynamics in liquid steel under RH vacuum conditions

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Journal of Iron and Steel Research International 2024年第4期31卷 828-837页

作者： Gu-jun chen sheng-ping He College of Materials Science and Engineering Yangtze Normal UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

Single argon bubble dynamics in liquid steel under Ruhrstahl-Heraeus(RH)vacuum conditions were simulated using the volume of fluid method,and the ideal gas law was used to consider bubble growth due to heat transfer and pressure *** simulation with a constant bubble density was also performed to validate the numerical method,and the predicted terminal bubble shape and velocity were found to agree with those presented in the Grace diagram and calculated by drag correlation,*** simulation results under RH conditions indicate that the terminal bubble shape and velocity cannot be *** primary bubble growth occurs within a rising distance of 0.3 m owing to heating by the high-temperature liquid steel;subsequently,the bubble continues to grow under equilibrium with the hydrostatic *** the initial diameter is 8-32 mm,the bubble diameter and rising velocity near the liquid surface are 80-200 mm and 0.5-0.8 m/s,*** bubble rises rectilinearly with an axisymmetric shape,and the shape evolution history includes an initial sphere,(dimpled)ellipsoid,and spherical cap with satellite bubbles.

关键词： Bubble dynamics Liquid steel Volume of fluid Bubble growth Bubble shape Rising velocity

Prediction of liquid circulation flow rate in RH degasser:improvement of decarburization at low atmospheric pressure

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Journal of Iron and Steel Research International 2024年第7期31卷 1661-1667页

The two-fluid model coupled with population balance model was used for simulating the gas-liquid flow in the Ruhrstahl-Heraeus(RH)*** predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical ***,influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa,*** result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric ***,increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric *** test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion *** optimization,the percentage of heats with a final carbon content less than 0.002 wt.%is significantly increased from 22.0%to 96.4%.

关键词： RH degasser Two-fluid model Population balance model-Circulation flow rate Decarburization Snorkel immersion depth