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Influences of finite-size effects.on the self-organized critical-ity of forest-fire model

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Chinese Science Bulletin 2002年第3期47卷 177-180页

作者： Weiguo Song Weicheng Fan Binghong Wang Univ Sci & Technol China State Key Lab Fire Sci Hefei 230026 Peoples R China

The influences of finite-size effects.on the self-organized criticality (SOC) of the traditional forest-fire model are investigated by means of a new method. The forest size is originally set to a value much greater than the correla-tion length of the forest. Finite-size effects.are then studied by equally dividing the forest into more and more separate subsystems on condition that the forest size, igniting prob-ability and planting probability are invariant. A new phe-nomenon, i.e. the finite-size effects.with one-side frequency peak, is observed. The boundary between two neighboring subsystems can be regarded as a firebreak. The concept of ’separation ability’ is introduced to represent the probability for the firebreak to block off the fire successfully. Restrain-ing effects.of separation ability on finite-size effects.are ana-lyzed. Finite-size effects.and separation ability, as well as their relations are found to have practical importance to the actual forest-fire protection.

关键词： forest-fire model self-organized criticality cellular automata finite-size effects.

FIVE ISLANDS effects.OF SHANGHAI URBAN CLIMATE

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Science China Chemistry 1990年第1期33卷 67-78页

作者：周淑贞 Department of Geography East China Normal University Shanghai 200062 PRC

By combining the anthropogenic condition (the change of urban surface nature, the emission of anthropogenic heat and pollutant) and the weather condition (the large-scale air circulation and local weather situation), the author clarified the formative processes, features and relationship of the five islands (heat island, dry island, moisture island, rain island and turbidity island) effects.of Shanghai urban climate. This research is not only important to the theoretical problem of how the man’s activities influence the climate, but also provides scientific basis for urban weather prediction, urban air pollution protection and urban design.

关键词： urban climate Shanghai climate effects.

Modified Magnetohydrodynamic Model of Magnetic Reconnection

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Chinese Physics Letters 1999年第6期16卷 461-463页

作者： ZHOU Guo-cheng CAI Chun-lin CAO Jin-bin ZHANG Yang-ting CHEN Tao WANG De-ju Center for Space Science and Applied Research Chinese Academy of SciencesBeijing 100080

This paper presents the modified magnetohydrodynamic(MHD)model and simulations of solar wind-magnetosphere *** use the two-dimensional and three-component,compressible,resistive,ion gyroviscous and Hall MHD model,i.e.,including the ion Unite Larmor radius(FLR)and Hall MHD effects.but neglecting the electron inertia and electron FLR *** composed dynamic pressure pulses(shear variations in the How velocity)in the solar wind form gusts that continually buffet the magnetosphere and cause the time-dependent magnetic reconnection at the *** results show that the magnetic Held and the How velocity components perpendicular to the reconnection plane can be generated in magnetopause current *** vortical How structures can also occur in the magnetospheric side *** results are responsible for non-ideal MHD properties of the plasma fluid,i.e.,ion FLR and Hall MHD effects.

关键词： reconnection effects. inertia

Major thrust sheet in the Daqing Shan Mountains, Inner Mongolia, China

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Science China Earth Sciences 1998年第5期41卷 553-560页

作者：郑亚东 G.A.Davis 王琮 B.J.Darby 华永刚 1. Department of Geology Peking University 100871 Beijing China 2. Department of Geosciences University of Southern California 90089 California Los Angeles USA

Small thrust faults in the Daqing Shan that were previously mapped as separate structures belong to a single Mesozoic thrust, herein named the Daqing Shan thrust. It extends more than 155 km along the northern margin of the Daqing Shan, obliquely cutting the Daqing Shan along the western flank of the Jinluandian peak to the southeast and taking its way to Chayouzhongqi to the east. Kinematic markers indicate tectonic transport of the thrust sheet to the NNW. Minimum displacement, based on the observable outcrops, is 22 km, and the inferred thrusting distance may be larger than 35 km. The thrust sheet covers the whole eastern area of the Daqing Shan. The thrust truncates the E-W trending, somewhat older South-directed Panyanshan thrust and, therefore, the two faults are not as a result of counter thrusting. Such major intraplate tectonic deformation that occurred in the Inner Mongolia Axis or the Yin Shan latitudinal tectonic belt during late Jurassic time calls for deep thought on its tectonic significance in dynamics. It is most likely that the Daqing Shan thrust represents major intraplate shortening during Jurassic-Cretaceous closure of the Mongolo-Okhotsk ocean about 1000 krn away to the north.

关键词： Daqing Shan late Jurassic major intraplate thrust Mongolo\|Okhotsk ocean far\|field effects.

The nutrient forms, cycling and exchange flux in the sediment and overlying water system in lakes from the middle and lower reaches of Yangtze River

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Science China Earth Sciences 2006年第z1期49卷 1-13页

作者： QIN Boqiang ZHU Guangwei Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China

This paper is a review of research works concerning the nutrient transportation, transformation and exchange between water, sediment and biota in the lakes from the middle and lower reaches of the Yangtze River conducted in the context of project entitled 'The Processes and Mechanism of Lake Eutrophication in Middle and Lower Reaches of Yangtze River'. All the lakes from this area are shallow lakes. According to the typical lake site research, the lakes from the middle and lower reaches of Yangtze River have a higher baseline of nutrition in the history. Normally the trophic status of these lakes can be categorized into medium-trophic or eutrophic. Human activities have been enhanced during the last decades, which speed up the lake eutrophic process. Lake eutrophication control needs to reduce not only the external nutrient inputs from watershed but also the internal loading from the sediments. Investigations revealed that the lake sediments in this area are considerablly high in nutrition in which at most about 30% of phosphorus exists in the form of bio-available in the sediment. The surface sediment will exert great effects.on the nutrient exchange between water-sediment interface via adsorption and release of nutrient. The nutrient release from the sediment in these shallow lakes is mainly in two ways, i.e. in the undisturbed condition the nutrient is released through diffusion created by the nutrient gradient from sediment to overlying water; whereas in disturbed condition, the nutrient release is determined by the hydrodynamic forcing intensity and the sediment resuspension. Metallic elements such as the iron, manganese and aluminium and the aerobic-anaerobic ambience will affect the release of nutrients. The disturbed release will increase the total nutrients in the water column significantly in the short period. At the beginning of sediment resuspension, the dissolved nutrient concentration will increase. This increase will be damped if the ferric oxide and

关键词： shallow lakes, nutrient baseline, internal nutrient release, microbial effects.

Glycyrrhizin-Induced Pseudohyperaldosteronism:A Case Report

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Chinese Journal of Integrative Medicine 2022年第7期28卷 644-649页

作者： FAN Zong-jing LIU Jin-min LI Xing-xing CUI Jie GUO Bin LIN Quan ZHUANG Rui WU Zheng-bo WU Yang Department of Cardiology Dongfang HospitalBeijing University of Chinese MedicineBeijing 100078China Department of Graduate School Beijing University of Chinese MedicineBeijing 100029China Department of Cardiology Xiyuan HospitalChina Academy of Chinese Medical SciencesBeijing 100091China

Licorice,also known as Radix Glycyrrhizae,is a natural sweetener and widely used as a drug,and it has been considered to be a healthy natural substance with few side effects.;Pseudo hyperaldosteronism(PsHA),which is characterized by hypertension,hypokalemia and alkalosis,should be considered when licorice or its related products are excessively ingested.

关键词： effects. ster ism

On density perturbations and missing mass

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Science China Mathematics 2002年第4期45卷 528-532页

作者：王永久唐智明 1. Institute of Physics Hunan Normal University 410081 Changsha China

In inflation the influence of short wave part of scalar field on the long wave is considered to be a nature of a random force possessing simple statistical properties. A unified cosmology is proposed. Some interesting... 详细信息

关键词： gravitational field, Dirac equations, gravitational effects.

Theoretical studies of rovibrational spectrum and potential energy function for Ar-N_2 complex

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Chinese Science Bulletin 1996年第23期41卷 1972-1976页

作者：鄢国森谢军楷谢代前 Department of Chemistry Sichuan University Chengdu 610064 China

The Ar-N2 complex plays an important role in atmosphere ***,thepotential energy functions（PEF）CPV,BTT,MMSV,M3SV,MMSV’ have beendetermined by comparing the relevant experimental information,such as the molecular beamscattering measurements,virial coefficient data,bulk transport and relaxation phenomena,pressure-broadening and shift of spectroscopic infrared and Raman ***

关键词： potential energy function van der Waals vibrational states intensity and isotope effects.

THE OPTIMIZED EXPANSION FOR SINE-GORDON FIELD THEORY AT ZERO AND FINITE TEMPERATURES IN D+1 DIMENSIONS

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Science China Mathematics 1991年第1期34卷 68-78页

作者：楼森岳倪光炯 Department of Physics Ningbo Normal College Ningbo 315211 PRC Department of Physics Fudan University Shanghai 200433 PRC

By means of the optimized expansion technique, the D + 1-dimensional quantum sine-Gordon (sG) field theory is studied nonperturbatively for both zero and finite *** 1 + 1 and 2+ 1 dimensions, the theory is finite when momentum cutoff Λ tends to *** temperature-dependent Coleman phase transition conditions we obtained reduce to theknown results g_(cr)~2 =8π for 1+ 1 dimensions and g_(cr)~2= 16π/m_(RO) for 2+ 1 dimensions whenT→0. Especially, g_(cr) tends to zero at T→∞ limit both for 1 + 1 and 2 + 1 dimensions. Thereis no critical temperature making the Φ= 0 vacuum unstable. In 3 + 1 dimensions, if g^2 isfinite and Λ→∞, the theory is trivial. There is no nontrivial 'precarious' phase for the3+ 1-dimensional sG model. The effective potential for the 'autonomous' phase has asimilar form as the classical potential and the temperature effects.only make contribution tothe infinitesimal part of this phase.

关键词： optimized expansion Coleman phase transition temperature effects.