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Bioavailable phosphorus distribution in alpine meadow soil is affected by topography in the tian shan Mountains

Journal of Mountain Science 2020年第2期17卷 410-422页

作者： LI Fa-Yong YUAN Cheng-yu YUAN Zi-Qiang YOU Yong-jun HU Xue-fei WANG shan LI Guo-yu College of Water Resources and Architectural Engineering Tarim UniversityXinjiang 843300China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China

Phosphorus(P) bioavailability is an important factor in alpine meadows and plays an important role in the response to climate change and the maintenance of ecosystem ***,little is known about how environmental factors,such as elevation and slope aspect,affect soil P *** explored the effects of elevational gradient and slope aspect on different forms of P and P availability in the alpine meadows on the southern slope of the tian shan Mountain *** P was found to be 851.9-1556.7 mg·kg^(-1) at different elevational gradients and 437.5-1547.0 mg·kg^(-1) at different slope aspects,and highest at 3337 and 3652 m.a.s.l.,but little differences between slope *** P and Labile P linearly increased with the elevational *** valley and the base of the shady slope had higher contents of H_***_3-Pi,and NaHCO_3-Po,and high-active organic P(NaHCO_3-Po,NaOH-Po,and H_2O-Po) was positively correlated with soil total carbon(TC),total nitrogen(TN),soil organic carbon(SOC),and aboveground biomass(AGB),but was negatively correlated with pH,aluminum(Al),and calcium(Ca) at different elevational ***-active bioavailable P(H_2OPi,H_2O-Po,NaHCO_3-Pi,and NaHCO_3-Po) was positively correlated with soil SOC and AGB and was negatively correlated with pH at different slope *** results suggest that soil P availability in alpine meadows is significantly controlled by topographical factors and the valleys and base of shady slopes are reservoirs of high-active bioavailable P.

关键词： Soil phosphorus Altitude Shady aspect Sunny aspect Phosphorus forms

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LATE CENOZOIC TECTONICS ALONG THE NORTHWESTERN MARGIN OF THE TARIM BASIN: INTERACTIONS BETWEEN THE TARIM BASIN AND THE SOUTHERN tian shan, WEST CHINA

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地学前缘 2000年第S1期7卷 323-325页

作者： Chen Jie 1, Qu Guosheng 1, Shen Jun 2, Edward Sobel 3, Nan Ling 4, tian Qinjian 5,Yin Jinhui 1 (1 Institute of Geology, China Seismological Bureau, P.O.Box 9803, Beijing 100029,China, E\|mail chenjie@*** 2.Seismological Bureau of X

The Late Cenozoic fold\|and\|thrust zone along the northwestern margin of the Tarim Basin and the adjacent tian shan of Central Asia is an actively deforming part of the India\|Asia collision system. This deformation zone has two remarkable oppositely vergence arcuate fold\|and\|thrust systems (Kepingtage and Kashi\|Atushi fold\|and\|thrust belts) reaching from east of Keping to west of Kashi. This shape is manifested by structure, topography and seismicity. From north to south, this deformation zone is characterized by four main kinematic elements: (1) a hanging\|wall block (Maidan fault and Tuotegongbaizi\|Muziduke thrust system) that represents the Cenozoic reactivation of a late Paleozoic thrust system; (2) an imbricated thrust stack (Kepingtage\|Tashipeshake thrust system) where slices of Tarim platform sediments are thrust south toward the basin; (3) the Kashi\|Atushi fold\|and\|thrust system where thrusting and folding verge toward the tian shan; (4) a foot\|wall block (Tarim craton) that dips gently northwest below the sediment\|filled southern tian shan basin and generally has little internal deformation.

关键词： Late Cenozoic tectonics Northwestern Tarim basin tian shan folding and thrusting shortening rate

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Effects of geometrical parameters on wrinkling of thin-walled rectangular aluminum alloy wave-guide tubes in rotary-draw bending

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Chinese Journal of Aeronautics 2013年第1期26卷 242-248页

作者： tian shan Liu Yuli Yang He State Key Laboratory of Solidification Processing Northwestern Polytechnical University

Inner flange and side wrinkling often occur in rotary-draw bending process of rectangular aluminum alloy wave-guide tubes, and the distribution and magnitude of wrinkling is related to geometrical parameters of the tubes. In order to study the effects of geometrical parameters on wrinkling of rectangular wave-guide tubes, a 3D-FE model for rotary-draw bending processes of thin-walled rectangular aluminum alloy wave-guide tubes was built based on the platform of ABA-QUS/Explicit, and its reliability was validated by experiments. Simulation and analysis of the influence laws of geometrical parameters on the wave heights of inner flange and side wrinkling were then carried out. The results show that inner flange wrinkling is the main wrinkling way to rectan- gular wave-guide tubes in rotary-draw bending processes, but side wrinkling cannot be neglected because side wrinkling is 2/3 of inner flange wrinkling when b and h are smaller. Inner flange and side wrinkling increase with increasing b and h; the influence of b on side wrinkling is larger than that of h, while both b and h affect inner flange wrinkling greatly. Inner flange and side wrinkling decrease with increasing R/h; the influence of h on inner flange and side wrinkling is larger than that of R.

关键词： Geometrical parameters Inner flange wrinkling Side wrinkling Simulation Thin-walled rectangular wave-guide tube Rotary-draw bending

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Effect of Quantum Fluctuation on Two-Dimensional Spatially Anisotropic Heisenberg Antiferromagnet with Integer Spin

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Communications in Theoretical Physics 2006年第6期45卷 1137-1146页

作者： JI An-Chun tian Guang-shan School of Physics Peking University Beijing 100871 China

In the present paper, we calculate the Gaussian correction to the critical value J^c⊥ caused by quantum spin fluctuation in a two-dimensional spatially anisotropic Heisenberg antiferromagnet with integer spin S. Previously, some authors computed this quantity by the mean-field theory based on the Sehwinger boson representation of spin operators. However, for S = 1, their result is much less than the one derived by numerical calculations. By taking the effect of quantum spin fluctuation into consideration, we are able to produce a greatly improved result.

关键词： spatially anisotropic Heisenberg model functional integration Schwinger boson representation

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Quantum Phase Transition in Quasi-two-dimensional Heisenberg Antiferromagnet with Single-Ion Anisotropy

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Communications in Theoretical Physics 2007年第1期47卷 171-180页

作者： JI An-Chun tian Guang-shan School of Physics Peking University Beijing 100871 China

In the present paper, we investigate the quantum phase transition in a spatially anisotropic antiferrornagnetic Heisenberg model of S =1 with single-ion energy anisotropy. By using the Schwinger boson representation, we calculate the Gaussian correction to the critical value J⊥^c caused by quantum spin fluctuations. We find that, for the positive single-ion energy, a nonzero value of J⊥^c is always needed to stabilize the antiferromagnetic long-range order in this model. It resolves a difference among literature and shows clearly that the effect of quantum fluctuations may qualitatively change a result obtained by the mean-field theories on lower-dimensional systems.

关键词： spatially anisotropic Heisenberg model single-ion anisotropy functional integration Schwinger-Boson representation

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Passive location using CDMA mobile communication system based on repeater equipment

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 32-38页

作者： tian Zeng-shan ZHOU Fei ZHANG tian-qi Department of Communication and Information Engineering ChongqingUniversity of Posts and Telecommunications Chongqing 400065 China

To overcome the drawback of a short operation range and low-resolution of a passive location system using a civil communication signal, the new idea that utilizes code division multiple access （CDMA） signal and repeater is disposed off. First, the CDMA passive location model and observation function are given, and the error source and error range are analyzed. Subsequently, the CDMA passive location algorithm in a repeater environment is described and simulated. The simulation result shows that the algorithm can provide the location value with high accuracy.

关键词： passive location civil communication signal,location model repeater equipment operation range

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Hepatic perfusion disorders: Etiopathogenesis and related diseases

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World Journal of Gastroenterology 2006年第20期12卷 3265-3270页

作者： Jin-Lin tian Jin-shan Zhang Department of Radiology Chinese PLA General Hospital Beijing 100853 China

In this article, we have reviewed the hepatic perfusion disorder （HPD）, etiopathogenesis of HPD and corresponding diseases. Review of the literature was based on computer searches （PubMed, Index Medicus） and personal experiences. We considered HPD reflects perfusion differences due to redistribution of arterial blood flow among segments, subsegments and lobes of the liver. The plain CT scan findings of HPD manifests as triangular or wedge-shaped areas of low attenuation. On contrast-enhanced CT scan, HPD manifests multiple （or single） transient wedge-shaped, rotundloid or irregular appearance, homogeneous hyperattenuation （in less cases, hypoattenuation） during the hepatic arterial phase （HAP） and isoattenuated or slightly hyperattenuated areas during the portal arterial phase. Dynamic enhanced magnetic resonance （MR） features are similar to enhanced CT scan. Angiographic findings include non-opacification of portal vein on portograms or wedge-shaped segmental staining in arterial and parenchymal phases on hepatic angiograms. The causes of HPD are arterioportal shunts （APS）, intrahepatic vascular compressions and portal vein occlusion, steal phenomenon by hypervascular tumors, vascular variations and any other unknown reasons. It is very important for radiologists to be familiar with the various appearances of HPD to avoid false-positive diagnosis of pseudolesions and not to overestimate the extent of the disease.

关键词： Etiopathogenesis Hepatic perfusion disorders Diseases

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Superconducting Correlations in Small Metallic Grains

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Communications in Theoretical Physics 2001年第12期36卷 705-714页

作者： WANG Jing JI An-Chun tian Guang-shan Department of Physics Peking University Beijing 100871 China Department of Physics Peking University Beijing 100871 China Department of Physics Peking University Beijing 100871 China

By applying the path-integral formulation and the Feynman theorem, we calculate the off-diagonal superconducting correlation in an ultrasmall metallic grain. Unlike its behavior in the bulk limit, we find that this correlation function is an intensive quantity in this case. Therefore, superconductivity is indeed completely suppressed by quantum fluctuations as the diameter of the grain shrinks to the nanometer scale. This conclusion confirms the previous results by numerical calculations. Furthermore, it also imposes a strong constraint on the delocalizing amplitude of the pair-mixing function, which was recently proposed to characterize superconductivity in the canonical *** numbers: ***, ***, 74.80.

关键词： ultrasmall superconducting grain, the off-diagonal correlation function, path integral formulation and resolvent expansion method

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Isolation and Crystal Structure of 1',4'-Trans-diol of Abscisic Acid

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1085-1089页

作者： WANG tian-shan ZHOU Jin-Yan TAN Hong Chengdu Institute of Biology The Chinese Academy of Sciences Chengdu 610041 China Department of Chemistry Hainan Normal University Haikou 571158 China

1 ′,4′-Trans-diol of abscisic acid was isolated from botrytis cinerea as a colorless crystal. The molecular and crystal structures have been determined by X-ray diffraction analysis. It crystallizes in orthorhombic system, space group P212121 with a = 6.724（3）, b = 17.559（6）, c = 12.265（2）,A,α =β=γ= 90°, V= 1448.1（8）,A^3, Z=4, Dx = 1.222 g/cm^3, F（000） = 576 and μ（MoKa） = 0.087 mm^-1. The final R = 0.0628 and wR = 0.1604 for 2501 independent reflections with Rint - 0.0160 and 1679 observed reflections with 1 〉2σ（I）. There are three intermolecular hydrogen bonds in a unit cell.

关键词： botrytis cinerea abscisic acid 1′,4′-trans-diol of abscisic acid X-ray diffraction analysis

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An efficient bi-objective optimization framework for statistical chip-level yield analysis under parameter variations

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Frontiers of Information Technology & Electronic Engineering 2016年第2期17卷 160-172页

作者： Xin LI Jin SUN Fu XIAO Jiang-shan tian Technology Innovation Center Jiangsu Academy of Safety Science and Technology Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing University of Posts and Telecommunications School of Computer Science and Engineering Nanjing University of Science and Technology

With shrinking technology,the increase in variability of process,voltage,and temperature(PVT) parameters significantly impacts the yield analysis and optimization for chip *** yield estimation algorithms have been limited to predicting either timing or power ***,neglecting the correlation between power and delay will result in significant yield *** of these approaches also suffer from high computational complexity and long *** suggest a novel bi-objective optimization framework based on Chebyshev affine arithmetic(CAA) and the adaptive weighted sum(AWS) *** power and timing yield are set as objective functions in this *** two objectives are optimized simultaneously to maintain the correlation between *** proposed method first predicts the guaranteed probability bounds for leakage and delay distributions under the assumption of arbitrary *** a power-delay bi-objective optimization model is formulated by computation of cumulative distribution function(CDF) ***,the AWS method is applied for power-delay optimization to generate a well-distributed set of Pareto-optimal *** results on ISCAS benchmark circuits show that the proposed bi-objective framework is capable of providing sufficient trade-off information between power and timing yield.

关键词： Parameter variations Parametric yield Multi-objective optimization Chebyshev affine Adaptive weighted sum

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