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| 1 | Optimal configuration for a finite high-temperature source heat engine cycle with the complex heat transfer law显示文摘The optimal configuration of a heat engine operating between a finite high-temperature source and an infinite low-temperature reservoir is derived by using finite time thermodynamics based on a complex heat transfer law,including Newtonian heat transfer law,linear phenomenological heat transfer law,radiative heat transfer law,Dulong-Petit heat transfer law,generalized convective heat transfer law and generalized radiative heat transfer law,q ∝(△T n). In the engine model the only irreversibility of finite rate heat transfer is considered. The optimal relation between the power output and efficiency of the heat engine is also derived by using an equivalent temperature of the hot reservoir. The obtained results include those obtained in recent literature and can provide some theoretical guidance for the designs of practical engines. | LI Jun CHEN LinGen SUN FengRui | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，4： | 22 |
| 2 | HYDRAULICS OF COMPOUND CHANNEL WITH VEGETATED FLOODPLAINS显示文摘Experimental researches were conducted on flood carrying capacity of compound open channels with wide and narrow floodplains as well as hydrodynamic behavior of overbank flow across vegetated floodplains. Results show that hydrodynamic behavior of compound channels with narrow floodplains is different from that of the wide floodplains. In such compound channels with narrow vegetated floodplains as in the Pearl River delta nework, it has been found that vegetated domains become really impenetra ble when the length of vegetated domain is larger than Lm, the length of f low in floodplain coming into the main channel, and that the influence of vegeta ted floodplains upon flood stages of a channel is not very significant. | Huang Ben-sheng, Lai Guan-wen, Qiu Jing, Lin Shu-zhong (Guangdong Research Institute of Water Conservancy & Hydro-Power, Guangzhou 510610, China | 2002 | Journal of Hydrodynamics2002，14，1： | 21 |
| 3 | Geological resources and environmental carrying capacity evaluation review,theory, and practice in China显示文摘Evaluations of resources and environmental carrying capacities (GRECC)are the premise of land space planning and use control.Resource allocations and environmental capacity are the basic conditions that restrict development in a region.In this paper,based on a systematic review of China's geological environment,groundwater resources,mineral resources,other geological resources and the environmental carrying capacity research status,the relationship between the natural resource environmental system and the socio-economic system is studied.Then a 'coordination theory of resources and environmental carrying'is proposed.Next,on the basis of an evaluation experiment performed at different scales and for different types of regions,the technical methods for an evaluation of the geological resources and environmental carrying capacity at the regional (inter-provincial)and provincial scales in China are established for the first time.This paper presents a standardized method based on technical ideas, evaluation methods,and index systems for geological resource and environmental carrying capacity evaluation.Finally,an evaluation of the groundwater resource carrying capacity in China is used as an example for the demonstration of the groundwater resource background and use of state evaluation methods. | Rui-min Li Zhi-qiang Yin Yi Wang Xiao-lei Li Qiong Liu Meng-meng Gao | 2018 | China Geology2018，1，4： | 19 |
| 4 | DEGREE OF SUBSTITUTION OF THE IONIZED STARCHES AND THEIR ADHESIVE CAPACITY TO POLYESTER / COTTON FIBERS显示文摘Adhesive capacity of quaternary ammonium starch and starch phosphate to the polyester / cotton fibers was studied by means roving method for the purpose of improving the sizing performance and decreasing the cost. By introducing different amount of quaternary ammonium or phosphate groups onto starch molecules, the modified starch with a series of defferent degree of substitution was prepared. Therefore the regularity of adhesive capacity, extended property and size-absorbing ability with the change in degree of substitution (DS) was obtained through the researches. The experiments demonstrate that the DS of the two modified starches show a marked influence upon the properties mentioned above. The starch phosphate is superior to quaternary ammonium starch as warp size for polyester / cotton yarns from the viewpoint of adhesive capacity and cost, although both of them are better than natural one. To improve the adhesive capacity to polyester / cotton fibers, DS≥0.027 is necessary for quaternary ammonium | 祝志峰 卓仁禧 | 1997 | Journal of China Textile University(English Edition)1997，14，1： | 19 |
| 5 | Theoretical analysis and experimental investigation on flexural performance of steel reinforced ultrahigh toughness cementitious composite (RUHTCC) beams显示文摘UHTCC (ultrahigh toughness cementitious composite), which is a kind of ultrahigh toughness cemen- titious composites material, exhibits pseudo strain hardening feature when subjected to tension load, and has enormous ductility and prominent crack dispersal ability. Accordingly, UHTCC can improve mechanical behavior of ordinary concrete structure especially its durability, and has been regarded as historical breakthrough to traditional cementitious materials. In this paper, the study focuses on flexure behavior of steel reinforced beam made of UHTCC. Based on the plane section assumption, along with two equilibrium equations of force and moment, the formulae to calculate the flexural load capability for the reinforced ultrahigh toughness cementitious composite (RUHTCC) beam were developed under the assumption that the compression stress- strain relationship in the UHTCC material is a bilinear model. Following this, the simplified formulae were further evolved by effective rectangle stress distribution approach in order to facilitate design of practical engineering. Two effective parameters introduced in effective rectangle approach were determined. The mathematical expressions to evaluate limited rein- forcement ratio, flexural stiffness as well as ductility index were proposed, too. Last, two series of dif- ferent reinforcement ratios of the RUHTCC beams were tested in four-point flexure loading. For com- parison purposes, ordinary RC (reinforced concrete) beams also were prepared. Both moment curva- ture curves and load mid-span displacement curves were recorded and compared with the theoretical calculations. A good agreement between them was found, which validates the proposed theoretical formulae. For ductility index, a slightly big difference between the experimental values and the calcu- lated ones exists. The experimental results show that, compared to control RC beams, the RUHTCC beam can improve both flexural capacity and ductility index, and the degree of improvement will de- crease with the increase in the reinforcement ratio. Particularly, the results also reveal that lager crack width in control beams can be greatly reduced by formation of tightly-spaced fine cracks in UHTCC, which offers more durable structures. | XU ShiLang ZHANG XiuFang | 2009 | Science China(Technological Sciences)2009，52，4： | 18 |
| 6 | Estimation of Undrained Bearing Capacity for Offshore Soft Foundations with Cyclic Load显示文摘The degradation strength of soils under cyclic loading is studied and a method for deter-mining the cyclic degradation strength with cyclic triaxial tests is given in the paper.Furthermore,a dum-my static method for estimating the undrained bearing capacity for offshore soft foundation under waveloads is developed.It can consider the effect of the difference of cyclic stress for different parts of the foun-dation on both the degradation strength of the foundation soil and the bearing capacity so that the esti-mated result can better reflect the real condition of foundation under cyclic loading.The method can be ap-plied to plane and space problem. | Wang, JH Liu, YF Xing, Y Di, HM | 1998 | China Ocean Engineering1998，13，2： | 18 |
| 7 | Donsker’s Invariance Principle Under the Sub-linear Expectation with an Application to Chung’s Law of the Iterated Logarithm显示文摘We prove a new Donsker’s invariance principle for independent and identically distributed random variables under the sub-linear expectation.As applications,the small deviations and Chung’s law of the iterated logarithm are obtained. | Li-Xin Zhang | 2015 | Communications in Mathematics and Statistics2015，3，2： | 17 |
| 8 | Understanding the biochar’s role in ameliorating soil acidity显示文摘Extensive acidic soils,which suffer from accelerated soil acidification,are found in southern China.Soil acidity,aluminum toxicity,and nutrient deficiencies severely limited crop productivity in acidic soils.It has been widely reported that crop residue biochars can ameliorate acidic soils and increase crop productivity.Here,we summarized the positive effects and mechanisms involved in the correction of soil acidity,the alleviation of aluminum toxicity and the increase of soil pH buffering capacity by crop residue biochars.The carbonate,oxygen-containing functional groups and silicates in biochars are the major components responsible for their efficacy in amending acidic soils and resisting soil re-acidification.We conclude that application of crop residue biochars may be a better option than traditional liming to ameliorate acidic soils.Nonetheless,further researches into soil acidification are still required to address some issues that are controversial and poorly understood. | SHI Ren-yong LI Jiu-yu NI Ni XU Ren-kou | 2019 | Journal of Integrative Agriculture2019，18，7： | 14 |
| 9 | 大跨度钢桁架拱桥的极限承载力研究显示文摘在强地震设防区或桥梁承受铁路荷载且地质条件良好时,钢桁架拱桥是理想的大跨度桥梁选择方案。以朝天门大桥和大宁河大桥为背景,从边界条件、初始状态、荷载要素等几个关键影响参数着手,对大跨度钢桁架拱桥的极限承载能力进行参数研究,指出活载的布置形式、侧向风荷载及不同的约束条件对钢桁架拱桥的极限承载力有较大影响。 | 方明霁 孙海涛 | 2010 | 世界桥梁2010，38，4： | 14 |
| 10 | POLYMER CHARGE AND MOLECULAR WEIGHT EFFECTS ON TREATED IRRIGATION FURROW PROCESSES显示文摘Application of 5-10 mg L-1 water soluble anionic polyacrylamide (PAM) to furrow irrigation water during flow advance substantially reduces sediment loss and increases net infiltration. We hypothesized that PAM_s solvated molecular conformation influences its irrigation-management efficacy. The study was conducted in Kimberly, Idaho, on Portneuf silt loam (Durinodic Xeric Haplocalcids), under furrowirrigated beans (Phaseolus vulgaris ) at a 1.5% slope. Polyacrylamides with contrasting molecular weight (anionic; 4-7, 12- 15 and 14-17 MDa, i.e. Mg mol-1 ), charge type (neutral, anionic, cationic), and charge density (8, 19, 35 mol %) were tested in two studies. Inflow rate was 23 L min-1 during furrow advance, and 15 L min-1 for the remaining set. Anionic and neutral PAMs were twice as effective as cationic PAMs for controlling sediment loss in new furrows. The order of effectiveness for overall soilloss control was : anionic >neutral >cationic PAM, and efficacy increased with increasing charge density and/or molecular weight. Net furrow infiltration increased by 14 to 19% when PAM treatment molecular weight was reduced from 17 to 4 MDa. General trends suggested that medium and high charge density anionic and neutral PAM produced the greatest increase in infiltration compared with controls.Compared with untreated furrows, neutral PAM gave the greatest season-long net infiltration gains (5%),while charged PAMs tended to increase net infiltration early in the season on new furrows but decreased infiltration on repeat-irrigated furrows later in the season. | R. D. Lentz(USDA-ARS, Northwest Irrigation and Soils Research Laboratory, Kimberly, ID)R. E. Sojka (Landcare Research, New Zealand, Ltd, Palmerston North, New ZealandNote: The manucript of this paper was received in March 1999, Discussion open until March | 2000 | International Journal of Sediment Research2000，15，1： | 13 |
| 11 | Modified activated carbon with interconnected fibrils of iron-oxyhydroxides using Mn^(2+) as morphology regulator, for a superior arsenic removal from water显示文摘The arsenic removal efficiency of iron-modified activated carbons depends greatly on the number of available iron oxide surface sites, which are given by the surface area of the anchored particles. In this sense, aiming the generation of an adsorbent with superior arsenic adsorption capacity, we developed a protocol to anchor interconnected fibrils of iron oxyhydroxides, using Mn^(2+) as a morphology regulator. The protocol was based on a microwave-assisted hydrothermal method, using bituminous based activated carbon and both Fe^(2+) and Mn^(2+) ions in the hydrolysis solution. The elemental analysis of modified carbons revealed that Mn does not anchor to the carbon. However, when Mn is included in the hydrolysis solution, the iron content in the activated carbon increased up to 3.5 wt%,without considerable decreasing the adsorbent surface area. Under specific hydrothermal conditions, the Mn^(2+) promoted the formation of iron oxide nanoparticles shaped as interconnected fibrils. This material showed a superior arsenic adsorption capacity in comparison to similar iron modified activated carbons(5 mg As/g carbon, at 2 mg As/L),attributed to the increase in quantity and availability of active sites located on the novel interconnected fibrils of iron oxyhydroxides nanostructures. | Cesar Nieto-Delgado Joel Gutiérrez-Martínez J.Rene Rangel-Méndez | 2019 | Journal of Environmental Sciences2019，31，2： | 12 |
| 12 | Performance-based methodology for assessing seismic vulnerability and capacity of buildings显示文摘This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved capacity- demand-diagram method. The spectral displacement (Sd) of performance points on a capacity curve is used to estimate the damage level of a building. The relationship between Sd and peak ground acceleration (PGA) is established, and then a new vulnerability function is expressed in terms of PGA. Furthermore, the expected value of the seismic capacity index (SCev) is provided to estimate the seismic capacity of buildings based on the probability distribution of damage levels and the corresponding seismic capacity index. The results indicate that the proposed vulnerability methodology is able to assess seismic damage of a large number of building stock directly and quickly following an earthquake. The SCev provides an effective index to measure the seismic capacity of buildings and illustrate the relationship between the seismic capacity of buildings and seismic action. The estimated result is compared with damage surveys of the cities of Dujiangyan and Jiangyou in the M8.0 Wenchuan earthquake, revealing that the methodology is acceptable for seismic risk assessment and decision making. The primary reasons for discrepancies between the estimated results and the damage surveys are discussed. | Lin Shibin1, Xie Lili1, 2,Gong Maosheng1,2 and Li Ming1,3 1.Institute of Engineering Mechanics,China Earthquake Administration, Harbin 150080, China 2.School of Civil Engineering,Harbin Institute of Technology,Harbin 150090, China 3.School of Civil Engineering,Shenyang Jianzhu University,Shenyang 11016, China | 2010 | Earthquake Engineering and Engineering Vibration2010，9，2： | 12 |
| 13 | Optimal allocation of hybrid energy storage for microgrids based on multi-attribute utility theory显示文摘To satisfy the requirements of high energy density,high power density,quick response and long lifespan for energy storage systems(ESSs),hybrid energy storage systems(HESSs)have been investigated for their complementary characteristics of‘high energy density components’and‘high power density components’.To optimize HESS combinations,related indices such as annual cost,fluctuation smoothing ability as well as safety and environmental impact have to be evaluated.The multiattribute utility method investigated in this paper is aimed to draw an overall conclusion for HESS allocation optimization in microgrid.Building on multi-attribute utility theory,this method has significant advantages in solving the incommensurability and contradiction among multiple attributes.Instead of determining the weights of various attributes subjectively,when adopting the multi-attribute utility method,the characteristics of attributes and the relation among them can be investigated objectively.Also,the proper utility function and merging rules are identified to achieve the aggregate utility which can reflect comprehensive qualities of HESSs. | Xiaoshan FENG Jie GU Xuefei GUAN | 2018 | Journal of Modern Power Systems and Clean Energy2018，6，1： | 11 |
| 14 | 基于PS-DR-DP理论模型的区域资源环境承载力综合评价(英文)显示文摘The concepts of regional resources and environmental carrying capacity are important aspects of both academic inquiry and government policy. Although notable results have been achieved in terms of evaluating both these variables, most researchers have utilized a traditional analytical method that incorporates the 'pressure-state-response' model. A new approach is proposed in this study for the comprehensive evaluation of regional resources and environmental carrying capacity; applying a 'pressure-support', 'destructiveness-resilience', and 'degradation-promotion'('PS-DR-DP') hexagon interaction theoretical model, we divided carrying capacity into these three pairs of interactive forces which correspond with resource supporting ability, environmental capacity, and risk-disaster resisting ability, respectively. Negative carrying capacity load in this context was defined to include pressure, destructiveness, and degradation, while support, resilience, and promotion comprised positive attributes. The status of regional carrying capacity was then determined via the ratio between positive and negative contribution values, expressed in terms of changes in both hexagonal shape and area that result from interactive forces. In order to test our 'PS-DR-DP' theory-based model, we carried out a further empirical study on Beijing over the period between 2010 and 2015. Analytical results also revealed that the city is now close to attaining a perfect state for both resources and environmental carrying capacity; the latter state in Beijing increased from 1.0143 to 1.1411 between 2010 and 2015, an improved carrying capacity despite the fact that population increased by two million. The average contribution value also reached 0.7025 in 2015, indicating that the city approached an optimal loading threshold at this time but still had space for additional carrying capacity. The findings of our analysis provide theoretical support to enable the city of Beijing to control population levels below 23 million by 2020. | 王亮 刘慧 | 2019 | Journal of Geographical Sciences2019，29，3： | 11 |
| 15 | A MATHEMATICAL MODEL FOR RESERVOIR SEDIMENTATION AND FLUVIAL PROCESSES显示文摘This paper consists of two parts: mechanism of non-equilibrium transport of non-uniform sediment and its application in the mathematical model. Based on a statistic approach of sediment transport proposed by the authors, a 1 - D equation of non-e- quilibrium transport for various size group of sediment particles is developed. Then equations to predict change of sediment concentration and the corresponding changes in size distribution of suspended load and bed material are also derived. The conception that changes in size distribution are interrelated to sediment-carrying capacity is expounded. These results reveal the essence of sediment transport of non-uniform sediment particles. In the second part a mathematical model incorporating the mentioned equations to compute deposition and scouring in reservoirs as well as the fluvial processes of river channels has been developed. Verification of the model agrees well with field data. | Han Qiwei and He Mingmin (Senior Research Engineers, Dept. of Sedimentation Eng. Inst. of Water Conservancy and Hydroelectric Power Research.) (The English text is abridged, altered and edited by Ding Lianzhen) | 1990 | International Journal of Sediment Research1990，5，2： | 10 |
| 16 | Ecological vulnerability analysis of Beidagang National Park,China显示文摘Ecological vulnerability analysis (EVA) is vital for ecological protection,restoration,and management of wetland-type national parks.In this study,we assessed the ecological vulnerability of Beidagang National Park based upon remote sensing (RS) and geographic information system (GIS) technologies.To quantify the ecological vulnerability,10 indices were collected by the 'exposuresensitivity- adaptive capacity' model and spatial principal component analysis (SPCA) was then applied to calculate the ecological vulnerability degree (EVD).Based on the numerical values,EVD of the study area was classified into five levels: moderate,light,medium,strong,and extreme.Results showed that the average EVD value was approximately 0.39,indicating overall good ecological vulnerability in Beidagang National Park.To be specific,80.42% of the whole area was assigned to a moderate level of EVD with the highest being the tourism developed areas and the lowest being the reservoirs and offshore areas.Ecological vulnerability of the region was determined to be affected by the natural environment and anthropogenic disturbance jointly.The primary factors included tourism disturbance,traffic interference,exotic species invasion,land use/land cover,and soil salinization.We expected to provide some insights of the sustainable development of Beidagang National Park and would like to extend the results to other wetland-type national parks in the future. | Xue YU Yue LI Min XI Fanlong KONG Mingyue PANG Zhengda YU | 2019 | Frontiers of Earth Science2019，13，2： | 10 |
| 17 | 中国人地关系评价的理论模型与实证(英文)显示文摘China’s coupled human-environment system(CHES) is assessed here via a systems schema that emphasizes the complex interactions of components and their attributes. In addition to the human and environment components, we identified two other components to evaluate the relationship. The four components are human activity intensity, resource carrying capacity, ecological constraints and system’s openness. Based on their interactions, we derived a cognitive schema for classifying the level of strain or stress of an area. The analysis draws on 11 indicators and 29 sub-indicators including remote sensing data and statistical data that are used to estimate the four components. The findings indicate that human activities are highly intense in a few geographical areas, particularly large urban systems and trade and investment zones on the eastern coastal areas. Nonetheless, these areas are also well-endowed in water resources and fertile soils although urban systems are increasingly stressed from negative pollution externalities. They are also open systems which allow them to bear a higher level of pressure and adjust accordingly. Desertification and soil erosion point to relatively fragile biophysical systems in the west and southwest, but human activities are still relatively less intense compared to their coastal counterparts. As a whole, only 14% of areas may be said to be relatively or highly strained. This however belies another one-third of areas that are currently unstable, and likely to become strained and thereby vulnerable in the near future. | 杨宇 李小云 董雯 POON PH Jessie 洪辉 何则 刘毅 | 2019 | Journal of Geographical Sciences2019，29，8： | 9 |
| 18 | Respiratory training interventions improve health status of heart failure patients: A systematic review and network meta-analysis of randomized controlled trials显示文摘BACKGROUND Prior studies indicate that doing breathing exercises improves physical performance and quality of life (QoL) in heart failure patients. However, these effects remain unclear and contradictory. AIM To determine the effects of machine-assisted and non-machine-assisted respiratory training on physical performance and QoL in heart failure patients. METHODS This was a systematic review and network meta-analysis study. A literature search of electronic databases was conducted for randomized controlled trials (RCTs) on heart failure. Respiratory training interventions were grouped as seven categories: IMT_Pn (inspiratory muscle training without pressure or < 10% maximal inspiratory pressure, MIP), IMT_Pl (inspiratory muscle training with low pressure, 10%-15% MIP), IMT_Pm (inspiratory muscle training with medium pressure, 30%-40% MIP), IMT_Ph (inspiratory muscle training with high pressure, 60% MIP or MIP plus aerobics), Aerobics (aerobic exercise or weight training), Qi_Ex (tai chi, yoga, and breathing exercise), and none. The four outcomes were heart rate, peak oxygen uptake (VO2 peak), 6-min walking distance test (6MWT), and Minnesota Living with Heart Failure QoL. The random-effects model, side-splitting model, and the surface under the cumulative ranking curve (SUCRA) were used to test and analyze the data. RESULTS A total of 1499 subjects from 31 RCT studies were included. IMT_Ph had the highest effect sizes for VO2 peak and 6MWT, IMT_Pm highest for QoL, and Qi_Ex highest for heart rate. Aerobics had the second highest for VO2 peak, Qi_Ex second highest for 6MWT, and IMT_Ph second highest for heart rate and QoL.CONCLUSION This study supports that high- and medium-intensity machine-assisted training improves exercise capacity and QoL in hospital-based heart failure patients. After hospital discharge, non-machine-assisted training continuously improves cardiac function. | Mei-Hua Wang Mei-Ling Yeh | 2019 | World Journal of Clinical Cases2019，7，18： | 9 |
| 19 | Rock support in strainburst-prone ground显示文摘Strainburst is the most frequently encountered type of rockburst in underground mines.Strainburst occurs when the stress near the excavation boundary reaches the peak strength of the rock mass causing it to fail suddenly and violently.To mitigate strainburst damage risk,effective rock support is needed.In strainburst-prone grounds,it is critical to have rock support components to fulfill the role of rock reinforcement first to prevent rock failure.On the other hand,well-retained and reinforced rock masses may be excessively deformed and fail violently.In such a case,yielding elements are needed in the rock support system to absorb the excess strain energy released due to rock failure.The conventional method to support strainburst-prone grounds is to install rock reinforcement system using rebar and mesh first and then install yielding support system using dynamic rockbolts at a later stage.This two-stage rock support installation process is not effective because it can adversely impact mine production schedule.This paper presents a new,patented dynamic rockbolt,which is called superbolt and is developed for rock support in burst-prone grounds.Laboratory testing confirmed that the superbolt has superb capacity to achieve the goal of reinforcing and holding rock masses.The superbolt is characterized by high dynamic energy absorption capacity,consistent performance,and the ability to withstand repeated dynamic loading.The new rockbolt can be used in a one-pass rock support system to facilitate rapid drift development in underground mines and increase mine safety and productivity. | M.Cai | 2019 | International Journal of Mining Science and Technology2019，29，4： | 9 |
| 20 | THE ADHESIVE CAPACITY OF STARCH GRAFT COPOLYMERS TO POLYESTER/COTTON FIBER显示文摘The advantages of using starch graft copolymers as warp sizes in textile were briefly discussed, and the factors of affecting adhesive capacity to the fiber were analysed. By using eerie ammonium nitrate as an initiator under nitrogen atomosphere, a number of vinyl and/or acrylic monomers such as acrylic acid, acrylamide, methyl acrylate, ethyl acrylate, butyl acrylate, hydroxyethyl acrylate, methyl methacrylate, butyl methacrylate, vinyl acetate and the combinations among them were graft copolymerized respectively onto granular corn starch in aqueous dispersion. The adhesive capacity of these starch graft copolymers to polyester/cotton fibers was evaluated by a slightly sized rovings according to V. K. Aggarwal’s method which measures the breaking strength and elongation of the rovings impregnated with the size paste. The influences of the monomers and their combinations, the grafting technological processes and the pretreatment methods before graft copolymerization upon adhesive capacity have been | 祝志峰 周永元 张文赓 欧石燕 | 1995 | Journal of China Textile University(English Edition)1995，12，1： | 8 |
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