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| 1 | Trace element geochemistry during chemical weathering——As exemplified by the weathered crust of granite, Longnan, Jiangxi显示文摘The granite weathering in Longnan, Jiangxi, is represented by mineralogical changes of feldspars · montmorillonite, illite · kaolinite, halloysite · bauxite, with Na, Ca, Si, P, V, U and Sr being in a mobile state while Ti, Al, Fe, Sc, Th, Zr and Hf remaining relatively conservative. With the exception of Zr/Hf, Nb/Ta, Th/Sc, Zr/Nd and Sm/Nb, changes are notable in ratios between most of the trace elements. Re-distribution of REE and Y has | Yingjun Ma Congqiang Liu | 1999 | Chinese Science Bulletin1999，44，24： | 35 |
| 2 | Effects of rare earth on inclusions and corrosion resistance of 10PCuRE weathering steel显示文摘The types, morphologies and distributions of nonmetallic inclusions in Cu-P weathering steels with and without rare earth were analyzed through a quantitative image analyzer, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) attached to SEM. Solid-soluble content of rare earth in the steels was analyzed by non-aqua electroanalysis and ICP. The results showed that rare earth modified the types and the morphologies of inclusions in the weathering steels. The small spherical rare earth oxysulfides and rare earth sulphides replaced the elongated MnS inclusions in the RE weathering steels. The rare earth inclusions dispersedly distributed and most inclusions were smaller than 2 μm in size. The optimum content of RE was 0.0065%-0.016% for 10PCuRE weathering steels containing about 0.002% oxygen and 0.004% sulfur. Solid-soluble content of rare earth in steels was (14-20)×10-6, which can act as a micro-alloying element. The corrosion resistance of 10PCuRE weathering steels and Q235 were studied by dry-wet cyclic immersion test. Their corrosion rates were obtained respectively. The polarization curves and pitting corrosion behaviors of weathering steels with and without rare earth were measured by electrochemical methods. The corrosion resistance of Cu-P weathering steels was improved by adding an appropriate amount of rare earth. Less and fewer rare earth inclusions largely decreased pitting susceptibility and rate of pit propagation. The pitting potential and the resistance against pitting corrosion of the RE weathering steel were significantly improved due to the modification of rare earth to inclusions. | 岳丽杰 王龙妹 韩金生 | 2010 | Journal of Rare Earths2010，28，6： | 25 |
| 3 | Geochemical studies on the intensity of chemical weathering in Luochuan loess-paleosol sequence, China显示文摘Major and trace element analyses of the Luochuan loess paleosol sequence in China were performed in order to understand the chemical weathering processes occurring on the Loess Plateau during the last 600 ka. Results reveal that most elements in the loess remain immobile during chemical weathering. The typical stable elements are Al, K, Ti, Rb and REE, while the main mobile elements are Ca, Sr, P, Mg and Na. Loess and paleosol experience the incipient stage of chemical weathering characterized by acid leaching and carbonate dissolution. Alteration of silicates in the sequence seems to be limited. Features of less chemical weathering of the loess and paleosol could be indicators for the dry cold climate dominated on the Loess Plateau during the Quaternary. | 陈骏 季峻峰 仇纲 鹿化煜 | 1998 | Science China Earth Sciences1998，41，3： | 22 |
| 4 | Chemical weathering and chemical runoffs in the seashore granite hills in South China显示文摘Surface runoffs and the contents of major ions and dissolved silicon were surveyed and analyzed based on weekly sampling for one year in a granite watershed of Zhuhai City, Guangdong Province. The results demonstrated that the slope runoff played an essential role in feeding the rivulet during precipitation, whereas the groundwater was more important for the rivulet in the non-raining stages. Dissolved silicon, Na+, HCO3-, and Clions constituted the major chemical components of the rivulet water. Atmospheric CO2 and H2SO4 sourced from the oxidation of pyrite were the main erosive mediums in the natural chemical weathering. Natural chemical weathering, the wet and dry deposition of sea-salt, and acids precipitation contributed approximately equal shares of anions to the rivulet water. The ratio of NO3- to SO42- was more than 1.0 in the runoff of the studied seashore watershed, whereas it is less than 1.0 in the Xijiang River that is adjacent to the study area. This implied that the chemical composition of runoff is controlled mainly by the differences in atmospheric acid precipitation caused by human activities and lithology within the catchments under the same bio-climate zone. The CO2 flux consumed by the rock chemical weathering processes within the seashore granite watershed in South China was (0.35-1.37)×105 mol km-2 a-1. | GAO QuanZhou & TAO Zhen School of Geography and Planning, Sun Yat-sen University, Guangzhou 510275, China | 2010 | Science China Earth Sciences2010，53，8： | 16 |
| 5 | Preliminary Study on weathering and pedogenesis of carbonate rock显示文摘South China is the largest continuous distribution area of carbonate rock in the world. The origin of the soils over the bedrock carbonate rock has long been a controversial topic. Here further exploration is made by taking five soil profiles as examples, which are developed over the bedrock dolomitite and limestone and morphologically located in upland in karst terrain in the central, west and north Guizhou as well as west Hunan, and proved to be the weathering profiles of carbonate rock by the research results of acid-dissolved extraction experiment of bedrock, mineralogy and trace element geochemistry. Field, mineralogical and trace element geochemical characteristics of weathering and pedogenesis for carbonate rock are discussed in detail. It is pointed out that weathering and pedogenesis of carbonate rock are important pedogenetic mechanisms for soil resources in karst area, providing a basis for further researches on the origin of soils widely overlying bedrock carbonate rocks in South China. | 王世杰 季宏兵 欧阳自远 周德全 郑乐平 黎廷宇 | 1999 | Science China Earth Sciences1999，42，6： | 13 |
| 6 | Origin of Tafoni in the Late Cretaceous Aeolian Sandstones,Danxiashan UNESCO Global Geopark,South China显示文摘Tafoni occur generally in granular rocks around the world, but their origin remains controversial. In this study,the roles of lithology, micro–climate, and organism in tafoni development are investigated in the Danxiashan UNESCO Global Geopark of South China. The Jinshiyan Temple and Luyitang sites along the Jinjiang River are chosen to conduct tafoni morphometry, bedrock petrography, and micro–climate analyses. The research methods used in this study include field observations and measurements, Voronoi diagrams, polarizing microscopic and scanning electron microscopic(SEM)image analysis, and meteorological detection. The tafoni are mostly 2–10 cm in length and elliptical in shape. The Late Cretaceous Jinshiyan sandstones are characterized by a grain–to–grain contact fabric and moderate sorting with a high proportion of soluble grains and cements. The Voronoi diagrams developed through the Arc GIS software are largely consistent with the tafoni openings. Moreover, owing to exposure to solar insolation, the external temperature values are higher than the internal ones, while the external relative humidity values are lower than the internal ones. Therefore, the permeable Jinshiyan sandstones are fundamental for tafoni development, while the abundant moisture from the Jinjiang River and frequent rains is favorable for salt weathering in tandem with biological activities. At last, a five–stage development model is proposed for the tafoni progression in the study area. | CHEN Liuqin GUO Fusheng LIU Fujun XU Huan DING Ting LIU Xin | 2019 | Acta Geologica Sinica(English Edition)2019，93，2： | 13 |
| 7 | Element geochemistry of weathering profile of dolomitite and its implications for the average chemical composition of the upper-continental crust——Case studies from the Xinpu profile, northern Guizhou Province, China显示文摘Geochemical behavior of chemical elements is studied in a dolomitite weathering profile in upland of karst terrain in northern Guizhou. Two stages can be recognized during the process of in situ weathering of dolomitite: the stage of sedentary accumulation of leaching residue of dolomitite and the stage of chemical weathering evolution of sedentary soil. Ni, Cr, Mo, W and Ti are the least mobile elements with reference to Al. The geochemical behavior of REE is similar to that observed in weathering of other types of rocks. Fractionation of REE is noticed during weathering, and the two layers of REE enrichments are thought to result from downward movement of the weathering front in response to changes in the environment. It is considered that the chemistry of the upper part of the profile, which was more intensively weathered, is representative of the mobile components of the upper curst at the time the dolomitite was formed, while the less weathered lower profile is chemically representative of the | 季宏兵 欧阳自远 王世杰 周德全 | 2000 | Science China Earth Sciences2000，43，1： | 12 |
| 8 | CHEMICAL BEHAVIOR OF CERIUM ELEMENT IN ROCK WEATHERING SYSTEM显示文摘1INTRODUCTIONTheelectronicstructureofgroundstateatomceriumisXe4f15d16s2,andtheelectronicstructureoftrivalentoxidizingstateisX... | Chi, Ru'an Zhu, Guocai Zhang, Ping Xu, Yinghui | 1999 | 中国有色金属学会会刊:英文版1999，9，1： | 10 |
| 9 | Climate and soil moisture environment during develop-ment of the fifth palaeosol in Guanzhong Plain显示文摘Based on weathering characteristics of the fifth palaeosol layer (S5) of four sections in Guanzhong Plain, the thickness of the weathered profile of the paleosol is determined to be greater than the ordi- nary soil, a weathered and leached loess layer thicker than 2 m. The distribution depth of the red argil- lans, the weathered and leached loess layer, Fe2O3, CaCO3 and Sr content under the S5 all indicate that the precipitation in Guanzhong Plain was over 900 mm at that time. The distribution depth of gravity water zone reached 4.2 m at least, and the soil moisture content was generally more than 20% within the range of 4.2 m. At that time there was sufficient soil moisture and no dried earth layer developed in Guanzhong Plain, suitable for the forest to develop. When this soil developed, the mean annual pre- cipitation was more than the annual soil moisture evaporation. The value of soil moisture balance was positive and the atmospheric precipitation could supply the underground water normally. Soil water was weak acidic in the middle and late stages when S5 developed in Guanzhong Plain. It was a kind of subtropical climate and even more humid and warmer than the northern edge of the subtropical climate zone in Guanzhong Plain when the S5 developed. At that time the subtropical climate was prevailing over the northern side and southern side of Qingling Mountains, showing the Mountains no longer to be the boundary between the subtropical zone and the temperate zone in China. The summer monsoon acted intensely and could go over Qingling Mountains frequently bring abundant precipitation. | ZHAO JingBo GU Jing DU Juan | 2008 | Science China Earth Sciences2008，51，5： | 9 |
| 10 | Characteristics and planation surface formation environment of the red weathering crust in Hunan, Guangxi,Yunnan,Guizhou and Tibet显示文摘The characteristics of red karst weathering crust in the research region can be divided into three subtypes. The first one includes the silicon to aluminum ratio, the composition of the clay minerals, etc., and reflects the weak action of de-silicon and aluminum enrichment. The second one, for example the granularity, shows that the viscous action is strong. The third one, such as the CaCO3 content and pH value, has regional difference in a large scale, which is consistent with the condition of modern scenery, so it is not important as for the ancient environment. | 崔之久 李德文 刘耕年 冯金良 张威 | 2001 | Science China Earth Sciences2001，44，S1： | 8 |
| 11 | Spatiotemporal evolution of carbon sequestration of limestone weathering in China显示文摘Carbonate carbon sequestration(CS) can aid in solving the problem of terrestrial residual carbon sinks and imbalances in the global carbon budget. Thus, complete understanding of the magnitude, spatiotemporal distribution, and evolution of this sequestration is highly desirable. On the basis of random forest regression and maximal potential dissolution model for carbonate, we estimated the CS of typical carbonate weathering in China from 2000 to 2014, that is, the sequestration of limestone weathering, using long-term ecologic, meteorological, hydrological raster data, and monitored data from 44 watersheds in China and surrounding regions. We extended our analyses by systematically exploring the spatiotemporal pattern and evolution trend of the flux and total sequestration. High levels of ionic activity coefficients of Ca^(2+) and HCO_3^- in limestone regions were observed to be mainly distributed in Northern and Northwestern China with a clear gradient from northwest to southeast. With a contrary spatial pattern, the annual average CS flux(CSF) of limestone weathering in China was estimated to be 4.28 t C km^(-2) yr^(-1), with high values mainly in the karst zones in Southeastern China. The mean CSF in different latitudes showed that Southern China(south of 28.14°N) was the region with the largest interannual fluctuation of flux and CSF increases as latitude decreases. The mean CSF in subtropical and tropical(TR) regions was the maximum of all major climate types, and for the frigid(F), mid-temperate(MTE), warm temperate(WTE), and temperate(TE) major climates; the CSF in the desert(D)subdivided climate was the minimum of these climates. By contrast, the values in grassland(G) and broad-leaved forest subdivided climate were the maximum. The pixel-based trend analysis indicated that the CSF of limestone weathering in China was slightly increasing in the period 2000–2014 with a rate of 0.036 t C km^(-2) yr^(-1). Furthermore, the annual total CS was estimated to be 7.07 Tg carbon per year(Tg C yr^(-1)) with high levels in 2002, 2008, and 2010, and the minimum appeared in 2011 with a slightly increasing trend of the total CS being observed with a rate of 0.06 Tg C yr^(-1). Tibet Autonomous Region was the administrative division with the largest total CS of limestone weathering(1.20 Tg C yr^(-1)) in China, and karst zones in Southeastern China had the largest total CS(4.95 Tg C yr^(-1)) which accounts for 70.01% of that in the three divided karst regions. On the basis of the diversity of rock chemical weathering carbon cycle mechanisms of different carbonate rock types, we estimated that the total CS of carbonate weathering in China may reach 11.37 Tg C yr^(-1)(the sink was approximately 5.02 t C km^(-2) yr^(-1)),which amounts to 16.20% of the total biomass CS in China, furthermore, the CSF of carbonate weathering in China can reach6.54 t C km^(-2) yr^(-1) if excluding the interference of the negative runoff. This finding indicates that CS of carbonate weathering is an indispensable part of China's terrestrial carbon sink system. The research pattern of this study was important for further improving the accuracy of the estimation for the global carbonate weathering carbon sink. | Huiwen LI Shijie WANG Xiaoyong BAI Yue CAO Luhua WU | 2019 | Science China Earth Sciences2019，62，6： | 7 |
| 12 | RARE EARTH PARTITIONING OF GRANITOID WEATHERING CRUST IN SOUTHERN CHINA显示文摘INTRODUCTIONTheweatheringcrustofSouthernChinaisaloosepolymineralaggregate,whichismainlycomposedofclaymineralsofkaolinite,hal... | Chi Ruan and Zhu Guocai Institute of Nuclear Energy Technology, Tsinghua University, Beijing 100084, P. R. China | 1998 | 中国有色金属学会会刊:英文版1998，8，4： | 7 |
| 13 | Surface grain refinement mechanism of SMA490BW steel cross joints by ultrasonic impact treatment显示文摘Ultrasonic impact treatment(UIT) is a postweld technique for improving the fatigue strength of welded joints. This technique makes use of ultrasonic vibration to impact and plastically deform a weld toe and can achieve surface grain refinement of the weld toe,which is considered as the main reason for the improvement of fatigue strength. In this paper,the microstructure of the surface of a treated weld toe was observed by metallographic microscopy and transmission electron microscopy(TEM). The results show that UIT could produce severe plastic deformation on the surface layer of the weld toe and the maximum depth of plastic deformation extended to approximately 260 μm beneath the treated surface. Repeated processing could exacerbate the plastic deformation on the surface layer,resulting in finer grains. We can conclude that the surface grain refinement mechanism of SMA490 BW welded joints is related to the high density of dislocation tangles and dislocation walls. | Bo-lin He Lei Xiong Ming-ming Jiang Ying-xia Yu Li Li | 2017 | International Journal of Minerals,Metallurgy and Materials2017，24，4： | 6 |
| 14 | Effect of tin addition on corrosion behavior of a low-alloy steel in simulated costal-industrial atmosphere显示文摘The effect of tin addition on the atmospheric corrosion behavior of a low-alloy steel in sim ulated coastalindustrial atm osphere has been investigated by indoor wet/dry cyclic corrosion test (CCT). The results indicate that tin addition can obviously make the steel substrate more resistant to atmospheric corrosion by suppressing the cathodic H^+ reduction reaction, and but tin addition is not of obvious beneficial effect when the steel is covered with a thicker rust layer during long-term corrosion process. The reason lies in the fact that the presence of un-reduced H^+ can lower the electrolyte pH value and lead to a loose and porous rust layer on tin-containing steel sample than that on tin-free steel sample. In addition, the 120 CCT cycles corrosion process of the two steels can be divided into three stages. Both the tin-free and tin-containing steels show an increasing corrosion rate during the initial corrosion stage and then exhibit a decreasing corrosion rate during the second and third corrosion stages. Moreover, tin addition makes the tin-containing steel rust layer have a higher amount of α-FeOOH and lower am ount of γ-FeOOH and Fe3O4 than the tin-free steel rust layer. | Bo Liu Xin Mu Ying Yang Long Hao Xueyong Ding Junhua Dong Zhe Zhang Huaxing Hou Wei Ke | 2019 | Journal of Materials Science & Technology2019，35，7： | 6 |
| 15 | Extension of drylands in northern China around 250 kaBP linked with the uplift of the southeast margin of Tibetan Plateau显示文摘Study on two loess sections, one located at Wu-wei near the Tengger Desert in northwestern China, another located near Ganzi at the southeast margin of the Tibetan Plateau in southwest China, reveals a coeval drying step occurred at -250 kaBP. It is expressed by the increase in eolian grain-size at Wuwei, and by a drastic extension of C4 plants and a decrease of loess chemical weathering intensity at Ganzi. Examination of the available eolian data indicates that the event has also been clearly documented in the loess sections near the deserts in northern China, and in the eolian records from the North Pacific. On the contrary, the signal is rather weak for the central and southern Loess Plateau regions as well as for Central Asia, where the climates are influenced by the southeast Asian monsoon and the westerlies, respectively. Since the climate at Ganzi is under strong control of the southwest Asian monsoon, we interpret this drying step as a result of decreased influence of the southwest summer | WU Haibin GUO Zhengtang FANG Xiaomin ZHANG Jiawu CHEN Fahu | 2002 | Chinese Science Bulletin2002，47，20： | 5 |
| 16 | The discovery and environmental significance of Chifeng wind route and huge pots of Inner Mongolia and Hebei Province显示文摘The pots discovered in Inner Mongolia and Hebei Province are huge with a maximum diameter of 9 m and a depth of 3.5 m, singular in shape,caused by weathering and wind erosion and have certain direction. They are a kind of typical climatic geomorphology. This | Zhijiu Cui Hongjiang Li Ling Nan Dewen Li | 1999 | Chinese Science Bulletin1999，44，16： | 5 |
| 17 | Leaching kinetics of rare earth from black weathering mud with hydrochloric acid显示文摘The affecting factors of leaching rate such as reacting temperature, mud particle size and concentration of reagents were determined by studying the leaching kinetics of rare earth from black weathering mud. The apparent activation energy is 9.08 kJ/mol from calculating the experimental data. The results show that the leaching process can be described by the shrinking core model and the leaching rate is controlled by diffusion of reacting reagents and reaction product in the porous solid layer. The leaching kinetics is established as: K =7.50×10 -5 ×exp(-9 080/ RT )/ r 2 0. | 池汝安 朱国才 田君 | 2000 | 中国有色金属学会会刊:英文版2000，10，4： | 5 |
| 18 | Effect of weathering on physico-chemical properties and combustion behavior of an Indian thermal coal显示文摘An open air stockpile of conical shape was formed with 3.5 m base diameter and 5 m height using 500 tons of -200 mm size ROM thermal coal on a concrete floor. Coal sample from the stockpile were collected at 30 days interval for analysis of various chemical properties like;proximate analysis, ultimate analysis, gross calorific value (GCV) and various combustion related properties such as ignition temperature, peak temperature, burnout temperature, maximum combustion rate, ignition index, burnout index, combustion performance index and combustion rate intensity index. Experimental results show that, due to weathering of coal fixed carbon decreased from 35.6% to 19.9%, elemental carb on (C) decreased from 46.6% to 28.6%, hydrogen (H) decreased from 3.3% to 2.9% and GCV decreased by up to 55% of original value during 330 days of storage of coal in an open atmosphere. Ash con tent of coal increased form 29.2% to 46.6% due to loss of combustibles. Sulfur (S) of coal was found to get increased from 0.33% to 1.08% during storage. The activation energy of coal combustion increased from 22 kJ/mol to 54 kJ/mol. Variation in combustion parameters signifies that weathering has significant negative impact on coal combustion properties as coal become difficult to ignite. | Subhajit Aich Barun Kumar Nandi Sumantra Bhattacharya | 2019 | International Journal of Coal Science & Technology2019，6，1： | 4 |
| 19 | Global cooling controls on the chemical weathering as evidenced from the Plio-Pleistocene deposits of the North China Plain显示文摘Major element concentrations were analyzed on the sediments of a 203.6-m core from the North China Plain near Tianjin. The chemical index of alteration (CIA), Al2O3-(CaO+Na2O)-K2O diagram and elemental ratios, such as Al/K and Ti/Na, were used to reveal information of chemical weathering in the source regions since the late Pliocene. Results show that the fluvial materials in the North China Plain were derived from vast regions, which were in the early Na and Ca removal stage and underwent numerous upper-crustal recycling processes. Proxies of chemical weathering show a decreasing trend, in parallel with the global cooling since the late Pliocene, suggesting a strong role of the global cooing in controlling the continental chemical weathering intensity. | YAO ZhengQuan1,2, XIAO GuoQiao1,2 & LIANG MeiYan2,3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2 Graduate University of the Chinese Academy of Sciences, Beijing 100049, China 3 Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China | 2010 | Chinese Science Bulletin2010，55，9： | 4 |
| 20 | Effect of Different Reinforcing Fillers on Properties,Interfacial Compatibility and Weatherability of Wood-plastic Composites显示文摘Utilization of biochar in plastic based blends offers a sustainable way to renewable materials as well as value-added use of wood waste.To investigate the interfacial compatibility and weatherability properties of biochar composites,four types of Wood-Plastic Composites(WPC)were prepared by an extrusion process.The mechanical properties,water absorptions,thermal and viscoelastic properties,and rheological behavior of the composites were also evaluated.The decolorizing carbon(NA)composite melts showed the higher modulus and viscosity,indicating better melt strength.The NA composites performed the best in tensile properties(strength of 2&6 MPa and modulus of 3.4 GPa)and had strong interfacial interaction between particles and the matrix.The degree of HDPE crystallinity in the biochar and carbon composites decreased relative to Douglas-fir(DF)composites,while the thermal properties of the composites improved compared with DF composites.For the water resistance,the DF composites displayed the highest water absorption(3.7%)and thickness swell(2.9%).During accelerated weathering tests,longer exposure time increased the color change and lightness,especially for DF composite.NA and biochar composites resulted in improved photostability.This study opens up a pathway to utilize effectively the renewable biochar as reinforcing filler in WPC in outdoor applications. | Xiaoqian Wang Zhiming Yu Armando G.McDonald | 2019 | Journal of Bionic Engineering2019，16，2： | 4 |
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