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| 1 | Prediction of permafrost distribution on the Qinghai-Tibet Plateau in the next 50 and 100 years显示文摘Intergovernmental Panel on Climate Change (IPCC) in 2001 reported that the Earth air temperature would rise by 1.4-5.8℃ and 2.5℃ on average by the year 2100. China re-gional climate model results also showed that the air temperature on the Qinghai-Tibet Plateau (QTP) would increase by 2.2-2.6℃ in the next 50 years. A numerical permafrost model was developed to predict the changes of permafrost distribution on the QTP over the next 50 and 100 years under the two climatic warming scenarios, i.e. 0.02℃/a, the lower value of IPCC’s estima-tion, and 0.052℃/a, the higher value predicted by Qin et al. Simulation results show that ( i ) in the case of 0.02℃/a air-temperature rise, permafrost area on the QTP will shrink about 8.8% in the next 50 years, and high temperature permafrost with mean annual ground temperature (MAGT) higher than ?0.11℃ may turn into seasonal frozen soils. In the next 100 years, perma-frost with MAGT higher than ?0.5℃ will disappear and the permafrost area will shrink up to 13.4%. (ii) In the case of 0.052℃/a air-temperature rise, permafrost area on the QTP will reduce about 13.5% after 50 years. More remarkable degradation will take place after 100 years, and permafrost area will reduce about 46%. Permafrost with MAGT higher than ?2℃ will turn into seasonal frozen soils and even unfrozen soils. | NAN Zhuotong LI Shuxun CHENG Guodong | 2005 | Science China Earth Sciences2005，48，6： | 40 |
| 2 | Variation of Cd concentration in various rice cultivars and derivation of cadmium toxicity thresholds for paddy soil by species-sensitivity distribution显示文摘It is imperative to derive an appropriate cadmium(Cd) health risk toxicity threshold for paddy soils to ensure the Cd concentration of rice grains meet the food safety standard. In this study, 20 rice cultivars from the main rice producing areas in China were selected, and a pot-experiment was conducted to investigate transformation of Cd in paddy soil-rice system with 0(CK), 0.3 mg kg–1(T1) and 0.6 mg kg–1(T2) Cd treatments in greenhouse. The results showed that Cd concentrations of rice grains existed significant difference(P<0.05) in 20 rice cultivars under the same Cd level in soil. The Cd concentrations of rice grains of the CK, T1 and T2 treatments were in the range of 0.143–0.202, 0.128–0.458 and 0.332–0.806 mg kg–1, respectively. Marked differences of the ratios of Cd concentration for soil to rice grain(BCFs) and transfer factors(TFs, root to grain and straw to grain) among the tested cultivars were observed in this study. The bioconcentration factors(BCFgrain) and TFs of the 20 rice cultivars were 0.300–1.112 and 0.342–0.817, respectively. The TFs of Cd from straw to grain ranged from 0.366 to 1.71, with significant differences among these 20 rice cultivars. The bioconcentration factors(BCFgrain) and TFs among the 20 rice cultivars ranged from 0.300–1.112 and 0.342–0.817, respectively. The species-sensitivity distribution(SSD) of Cd sensitivity of the rice species could be fitted well with Burr-III(R2=0.987) based on the data of BCFs. The toxicity threshold of Cd derived from SSD for the paddy soil was 0.507 mg kg–1 in the present study. | SONG Wen-en CHEN Shi-bao LIU Ji-fang CHEN Li SONG Ning-ning LI Ning LIU Bin | 2015 | Journal of Integrative Agriculture2015，14，9： | 33 |
| 3 | Study of spatial distribution of sandy desertification in North China in recent 10 years显示文摘Sandy desertification is a land degradation characterized by wind erosion, mainly resulted from the excessive human activities in arid, semiarid and part of sub-humid regions in North China. It is one of main kinds of desertification/land degradation as well as water-soil erosion and salinization in China. Rapid and continuous spread of sandy desertification during last 50 years has created a major environmental and socio-economic problem in North China. Remote sensing monitored results in 2000 showed that the sandy desertified land area has been 38.57×104 km2. The area of potential to slightly sandy desertified land is 13.93×104 km2, moderately land 9.977×104 km2, severely land 7.909×104 km2 and very severely land 6.756×104km2. Sandy desertification mainly occurs in the semi-arid mixed farming-grazing zone and its northern rangeland zone, semi-arid dryland rainfed cropping zone and arid oasis-desert margin zone. The average annually developmental rate of sandy desertified land increased from 2,100tion in North China is 'overall deterioration, while local rehabilitation'. Already achieved rehabilitation results and monitoring assessment show that about 60% of desertified land in North China can be restored under the conditions of rational land-use ways and intensity. | WANG Tao, WU Wei, XUE Xian, SUN Qingwei & CHEN GuangtingKey Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China Department of Environment Engineering, Peking University, Beijing 100871, China | 2004 | Science China Earth Sciences2004，47，z1： | 28 |
| 4 | Improvement of tree-like network constructal method for heat conduction optimization显示文摘The analysis of the “tree-like network” construct method has been repeated. The high effective conduction channel distribution has been optimized again, without the premise that the new order assembly construct must be assembled by the optimized last order construct. It is proved that the “tree-like network” construct method is faultiness. A more optimal construct is obtained, and when the thermal conductivity and the proportion of the two heat conduction materials are constant, the limit of the minimum heat resistance is derived. All these conclusions can be used to guide the engineering application. | WU Wenjun CHEN Lingen SUN Fengrui | 2006 | Science China(Technological Sciences)2006，49，3： | 25 |
| 5 | Hierarchical and probabilistic quantum state sharing via a non-maximally entangled stateHierarchical and probabilistic quantum state sharing via a non-maximally entangled stateHierarchical and probabilistic quantum state sharing via a non-maximally entangled state显示文摘A scheme that probabilistically realizes hierarchical quantum state sharing of an arbitrary unknown qubit state with a four-qubit non-maximally entangled 丨X) state is presented in this paper. In the scheme, the sender Alice distributes a quantum secret with a Bell-state measurement and publishes her measurement outcomes via a classical channel to three agents who are divided into two grades. One agent is in the upper grade, while the other two agents are in the lower grade. Then by introducing an ancillary qubit, the agent of the upper grade only needs the assistance of any one of the other two agents for probabilistically obtaining the secret, while an agent of the lower grade needs the help of both the other two agents by using a controlled-NOT operation and a proper positive operator-valued measurement instead of the usual projective measurement. In other words, the agents of two different grades have different authorities to reconstruct Alice's secret in a probabilistic manner. The scheme can also be modified to implement the threshold-controlled teleportation. | 彭家寅 柏明强 莫智文 | 2014 | Chinese Physics B2014，，1： | 20 |
| 6 | A sharp inequality for the tail probabilities of sums of i.i.d. r.v.'s with dominatedly varying tails显示文摘Let F be a distribution function supported on (-∞, ∞) with a finite mean μ. In this note weshow that if its tail F = 1 - F is dominatedly varying, then for any γ> max{μ, 0}, there exist C(γ) > 0 and D(γ) > 0 such thatC(γ)nF(x) ≤ Fn*(x) ≤ D(γ)nF(x),for all n ≥ 1 and all x ≥γn. This inequality sharpens a classical inequality for the subexponential distributioncase. | 唐启鹤 严加安 | 2002 | Science China Mathematics2002，45，8： | 20 |
| 7 | Eolian sedimentary records for the evolution of monsoon and westerly circulations of northern China in the last 2.6 Ma显示文摘Systematic grain-size analysis has found that Chinese loess generally shows bimodal distribution composed of overlapped coarse and fine components. Sedimentary dynamic illustra-tion indicates that the coarse component was mostly the product of low-level monsoonal circulation, and the fine component was mainly transported by high-level circulation dominated by westerly in northern China. Grain-size series of coarse component consistently indicates that the monsoonal circulation strengthened in glacial stages and weakened in interglacial stages over Loess Plateau. The latitude differentiation of fine component series suggests that the westerly circulation intensi-fied and shifted to about 35oN in glacial stages, conversely, weakened and shifted to 37oN in inter-glacial stages. Grain-size variation trends of coarse and fine components revealed by Luochuan loess-paleosol suggest that the contribution of westerly circulation to eolian loess decreased and its intensity weakened in the last 2.6 Ma, which is accompanied by strengthening intensity and increasing contribution of the monsoonal circulation. This variation trend was marked by an abrupt change in the transition period of 1.20.9 Ma, which probably reflected the controlling role of Tibet Plateau uplift on the atmospheric circulation of northern China. | 孙东怀 安芷生 苏瑞侠 鹿化煜 孙有斌 | 2003 | Science China Earth Sciences2003，46，10： | 16 |
| 8 | THE APPLICATION OF THE LAW OF MASS ACTION IN COMBINATION WITH THE COEXISTENCE THEORY OF SLAG STRUCTURE TO THE MULTICOMPONENT SLAG SYSTEMS显示文摘It is shown by the the law of mass action in combination with the coexistence theory of slag structure that KMn n =NMno /(NFeo [%Mn] does not change with basicities and maintains constant at constant temperature; the oxidizing capabilities of multicomponent slag systems containing CaO, MgO etc., can be expressed by NFe tO =NFeO + 6NFe2 O3 + 8NFe3O4; the desulfurizing capabilities of various basic oxides for multicomponent slag systems can be calculated by Ls=8(KCaSNCaO+KMgsNMgo +KFeSNFeO)∑n/[%O]; the dephosphorizing capabili- ties of CaO-MgO-FeO-FeO O3-P2 O5 as well as CaO-FeO-Fe2 O3-A12 O3-P2 O5 molten slags expressed respectively by Lpo=(%P2O5)/[P]2 = 141.94[%O]5∑nK00(1 + K5N2Cao + K6N3CaO + K7N4CaO + K8N2MgO + K9N3MgO + K10N3FeO + K11N4Feo); LPO=(%P2O5)/[P]2= 141.94[%O]5∑nK00(1 + K10N2CaO+ K11N3CaO+ K12N4CaO + K13N3FeO + K14N4FeO) have good agreement with practical values. | J. Zhang (Metallurgical Engineering School, University of Science and Technology Beijing, Beijing 100083, China) | 2001 | Acta Metallurgica Sinica(English Letters)2001，14，3： | 14 |
| 9 | Empirical likelihood confidence regions of the parameters in a partially linear single-index model显示文摘In this paper, a partially linear single-index model is investigated, and three empirical log-likelihood ratio statistics for the unknown parameters in the model are suggested. It is proved that the proposed statistics are asymptotically standard chi-square under some suitable conditions, and hence can be used to construct the confidence regions of the parameters. Our methods can also deal with the confidence region construction for the index in the pure single-index model. A simulation study indicates that, in terms of coverage probabilities and average areas of the confidence regions, the proposed methods perform better than the least-squares method. | XUE Liugen~1 & ZHU Lixing~2 1. College of Applied Sciences,Beijing University of Technology,Beijing 100022,China 2. Department of Mathematics,Hong Kong Baptist University,Hong Kong,China | 2005 | Science China Mathematics2005，48，10： | 13 |
| 10 | Study on the Relation between Garment Style and Ease Distribution显示文摘The shape of body and the ease of garment are the important elements in constructing garment style. However, the distribution of ease in garment is uneven and the curves showing different cross-sections of garment style with ease are unavailable in the literature. This information is crucial when the three-dimensional garment style is transformed into two-dimensional garment patterns. Thus, several different X-line style garments are produced by 3D draping technology, and the cubic spline is used to fit the cross sectional curves of BL, WL of body and garment. By comparing cross sections of body and garment, the ease at different location can be derived. Besides, garments in 10 different dimensions and quantities of style ease are included in the current study. By numerical operation on discrete ease data at different location, the fitted functions of ease distribution are obtained. | 王朝晖 张渭源 | 2004 | Journal of Donghua University(English Edition)2004，21，6： | 12 |
| 11 | One-step estimation for varying coefficient models显示文摘A one-step method is proposed to estimate the unknown functions in the varying coefficient models, in which the unknown functions admit different degrees of smoothness. In this method polynomials of different orders are used to approximate unknown functions with different degrees of smoothness. As only one minimization operation is employed, the required computation burden is much less than that required by the existing two-step estimation method. It is shown that the one-step estimators also achieve the optimal convergence rate. Moreover this property is obtained under conditions milder than that imposed in the two-step estimation method. More importantly, as only one minimization operation is employed, the full asymptotic properties, not only the asymptotic bias and variance, but also the asymptotic distributions of the estimators can be derived. The asymptotic distribution results will play a key role for making statistical inference. | TANG Qingguo & WANG Jinde Department of Mathematics, Nanjing University, Nanjing 210093, China Institute of Sciences, PLA University of Science and Technology, Nanjing 210007, China | 2005 | Science China Mathematics2005，48，2： | 11 |
| 12 | An asymptotic relationship for ruin probabilities under heavy-tailed claims显示文摘The famous Embrechts-Goldie-Veraverbeke formula shows that, in the classical Cramér-Lundberg risk model, the ruin probabilities satisfy R(x, ∞)~ p-1 e(x) if the claim sizes are heavy-tailed, where Fe denotes the equilibrium distribution of the common d.f. F of the i.i.d. claims, p is the safety loading coefficient of the model and the limit process is for x →∞. In this paper we obtain a related local asymptotic relationship for the ruin probabilities. In doing this we establish two lemmas regarding the n-fold convolution of subexponential equilibrium distributions, which are of significance on their own right. | 唐启鹤 | 2002 | Science China Mathematics2002，45，5： | 11 |
| 13 | Investigations on distributions and fluxes of sea-air CO_2 of the expedition areas in the Arctic Ocean显示文摘The distributions and fluxes of sea-air carbon dioxide were investigated the first time based on the firsthand data collected during the First Chinese National Arctic Research Expedition. The results revealed that values of atmospheric CO2 partial pressure (Pa) measured in the sum-mer during the expedition fell between 352 and 370 (10-6CO2·Air-1, same unit below) with an average value of 358. Particularly, Pa appeared high in the northern sea areas of Poitlay. However, the values of CO2 partial pressure at the surface layer of seawater (Pw) ranged from 98 to 580 with the difference between the low and high being 472. The average value of Pw was 242, which is 116 lower than that of the corresponding Pa. In addition, the distribution of Pw was roughly low in the west and north, but high in the east and south. These phenomena were closely related to plankton, ice, water temperature and circulation of the region. The estimation in carbon fluxes showed that the patterns in distribution were similar through different calculating methods with an exception in eastern sea areas of the region where a weak source of atmospheric CO2 was indi-cated. Most sea areas of the region were sinks or strong sinks of atmospheric CO2. However, the magnitudes in the fluxes were different. The average values varied from 6.57 (Liss method) to 26.32 mgCO2·m-2·h-1 (14C method) with a difference of about 4 times between the low and high, which is 2 to 10 times as high as the global average. Compared with the fluxes in the same region obtained using model of Takahashi, Feely et al., the values determined based on Wanninkhof coef-ficient calculation were 2.38 times as great as those obtained by them. | 王伟强 陈立奇 杨绪林 黄宣宝 | 2003 | Science China Earth Sciences2003，46，6： | 9 |
| 14 | Distributions of arsenic and essential elements in pinna of arsenic hyperaccumulator Pteris vittata L.显示文摘The distributions of arsenic and 6 essential elements in the pinna of As hyperaccumulator, Pteris vittata L., were studied using synchrotron radiation X-ray fluorescence (SRXRF). Significant correlation between the distribution and mobility of the elements revealed that SRXRF study on the elemental distribution was feasible to inspect the transportations of elements in plants. The distribution of As in the pinna showed that As had great abilities to be transported in xylem vessels and from xylem to mesophyll. The distribution of K, one of the most mobile elements in plants, was similar to that of As, whereas the distributions of Fe and Ca with less mobility in plants were almost opposite to that of As in the pinna. | CHEN Tongbin, HUANG Zechun, HUANG Yuying & LEI Mei Laboratory of Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Laboratory of Synchrotron Radiation, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100039, China | 2005 | Science China(Life Sciences)2005，48，1： | 7 |
| 15 | Characteristics of vertical ozone distribution in the lower troposphere in the Yangtze River Delta at Lin'an in the spring of 2001显示文摘We analyzed vertical distributions of ozone (O3) in the lower troposphere (< 5 km above ground) at Lin’an (119.75°E, 30.30°N), Zhejiang Province using electrochemical concen- tration cell (ECC) ozonesonde data obtained from February 21 to April 13, 2001. The results showed that the vertical O3 distributions are controlled by metrological conditions and the char- acteristics of O3 profiles are related to those of wet bulb potential temperature and wind field. O3 below 2 km showed that the strongest variability and enhanced O3 mixing ratios were associated with easterly winds that blow pollutants from the upwind source region of the Yangtze River Delta (YRD) region. Vertical O3 profiles below 5 km can be grouped into 5 categories: (1) peak mixing ratio type, (2) well-mixed type, (3) layered-structure type, (4) episodic pollution type and (5) alti- tudinal increasing type. Vertical distributions of O3 affected by regional transport of polluted air masses were investigated. Transport of polluted air from high latitudes of northern China, ac- companying subsiding motion of air and stagnant atmospheric conditions are important factors that lead to high mixing ratios of O3 at Lin’an. The stagnant atmospheric conditions associated with a continental high pressure system and pollution plume transported from the YRD and cen- tral-eastern China also lead to regional accumulation of O3 and high O3 mixing ratio at Lin’an. Long-range transport of O3 and pollutants from the Pearl River Delta in South China and in-situ O3 formation also resulted in elevated O3 mixing ratios at around 1 km altitudes and layered O3 distribution in the lower troposphere. | ZHENG Xiangdong1, CHAN Chuenyu2, CUI Hong2, QIN Yu3, CHAN Loyan2, ZHENG Yongguang3 & LEE Yusiang2 1. Chinese Academy of Meteorological Sciences, Beijing 100081, China 2. Department of Civil and Structural Engineering, Hong Kong Polytechnic University, Hung Hom, Hong Kong, China 3. Department of Atmospheric Sciences, Peking University, Beijing 100871, China | 2005 | Science China Earth Sciences2005，48，9： | 6 |
| 16 | Pore structure of new composite adsorbent SiO2·xH2O·yCaCl2 with high uptake of water from air显示文摘A new composite adsorbent SiO2@xH2O@yCaCl2 which is composed of macro-porous silica gel and calcium chloride is introduced. In order to analyze its adsorption theory, adsorption and desorption isotherms, BET surface areas, pore volumes and average pore diameters of macro-porous silica gel and four composite adsorbent samples with different CaCl2 content are measured using SEM and Asap2010 apparatus. From the adsorption isotherms, desorption isotherms and lag loops, it can be deduced that the main pore structure in macro-porous silica gel and the new composite adsorbent have two shapes: taper with one top open and taper or hyperbolic taper with both ends open. Based on the analysis of pore diameter distribution and lag loop, a sketch map showing calcium chloride filled in pore of macro-porous silica gel is presented. The adsorption isotherms at 25℃ are measured. Experimental results show that the new composite adsorbent can adsorb more water than common adsorbents (macro-porous silica gel, micro-porous silica gel and synthetic zeolite 13X). In the light of the results of pore structure, adsorption isotherms and lyolysis phenomenon are analyzed. | LIU Yefeng (刘业凤) WANG Ruzhu (王如竹) | 2003 | Science China(Technological Sciences)2003，46，5： | 6 |
| 17 | On the behavior of the product of independent random variables显示文摘For two independent non-negative random variables X and Y, we treat X as the initial variable of major importance and Y as a modifier (such as the interest rate of a portfolio).Stability in the tail behaviors of the product compared with that of the original variable X is of practical interests. In this paper, we study the tail behaviors of the product XY when the distribution of X belongs to the classes L and S, respectively. Under appropriate conditions, we show that the distribution of the product XY is in the same class as X when X belongs to class L or S, in other words, classes L and S are stable under some mild conditions on the distribution of Y. We also show that if the distribution of X is in class L(γ) (γ> 0) and continuous, then the product XY is in L if and only if Y is unbounded. | SU Chun CHEN Yu | 2006 | Science China Mathematics2006，49，3： | 5 |
| 18 | Geographic Distribution of Mating Types in Magnaporthe grisea and the Relationship Between Fertile Isolates in China显示文摘377 isolates of Magnaporthe grisea were collected from 17 provinces in China and their geographic distribution of mating types and their fertility was tested with four standard isolates, KA3 and TH12 (Mat1.1) and Guy11 and TH16 (Mat1.2) provided by CIRAD. 73 fertile isolates were tested with SCAR markers of 13 pairs of primers. Preliminary results showed that the geographic distribution of M. grisea existed among isolates collected from the same location as well as different locations and the genetic relationship between fertile isolates of the fungus in China. The existence of sexual reproduction of M. grisea was explored in the field as well. | SHEN Ying, Notteghem Jean Loup., Milazzo Joelle., YUAN Xiao-ping, Adreit Henry, ZHAO Xin-hua, WANG Yan-li and Tharreau Didier.(China National Rice Research Institute, Hangzhou 310006, P. R. China National Institute of Agronomic Research ,Unit of Training and Biological Research , Ecology and Plant Pathology, 2 Place Viala , 34062 Montpellier , France International Center for collaboration in Agronomic Research and Development,TA 73 /09 , 34398 Montpellier , Cedex 05 , France) | 2002 | Agricultural Sciences in China2002，1，6： | 5 |
| 19 | Evaluation of zeotropic refrigerants based on nonlinear relationship between temperature and enthalpy显示文摘In order to evaluate cycling characters of zeotropic refrigerants in air-con- ditioning operation, and to reveal distribution rules of temperature difference between refrigerants and heat transfer fluids in condenser and evaporator, theoretical researches were carried out based on nonlinear relationship between temperature and enthalpy in period of refrigerants’ phase change. Firstly, a phase changing model of refrigerants was built, and refrigerants state parameters were decided in the air-conditioning operation. Secondly, the state equation of refrigerants was applied for computing relationship be- tween temperature and enthalpy, else based on some suppositions, temperature differ- ences between 15 sorts of refrigerants and heat-transfer fluids were gotten too. Through concluding those temperature differences changing in condenser and evaporator, some rules were found. Lastly, after calculating and comparing the additive exergy loss among 15 sorts of refrigerants, which resulted from the changing of temperature difference, their cycling characters evaluation were presented. | ZHAO Li GAO Pan | 2006 | Science China(Technological Sciences)2006，49，3： | 4 |
| 20 | Application of ensemble kalman filter to geophysical parameters retrieval in remote sensing:A case study of kernel-driven BRDF model inversion显示文摘The use of a priori knowledge in remote sensing inversion has great implications for ensuring the stability of inversion process and reducing uncertainties in retrieved results, especially under the condition of insufficient observations. Common optimization algorithms have difficulties in providing posterior distribution and thus cannot directly acquire uncertainties in inversion results, which is of no benefit to remote sensing application. In this article, ensemble Kalman filter (EnKF) has been introduced to retrieve surface geophysical parameters from remote sensing observations, which has the capability of not merely obtaining inversion results but also giving its posterior distribution. To show the advantage of EnKF, it is compared to standard MODIS AMBRALS algorithm and highly effi-cient global optimization method SCE-UA. The inversion abilities of kernel-driven BRDF models with different kernel combinations at several main cover types are emphatically discussed when observa-tions are deficient and a priori knowledge is introduced into inversion. | QIN Jun1, YAN Guangjian1, LIU Shaomin1, LIANG Shunlin2, ZHANG Hao1, WANG Jindi1 & LI Xiaowen1 1. State Key Laboratory of Remote Sensing Science, School of Geography and Remote Sensing, Research Center for RS&GIS, Beijing Normal University, Beijing 100875, China 2. Department of Geography, 2181 Lefrak Hall, University of Maryland, College Park, MD20742, USA | 2006 | Science China Earth Sciences2006，49，6： | 4 |
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