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| 1 | Boron isotopic fractionation during incorporation of boron into Mg(OH)_2显示文摘Experiments of boron incorporated into Mg(OH)2 from magnesium-free synthetic seawater were carried out at various pH values, in order to investigate the adsorption species and the variation of isotopic fractionation of boron on Mg(OH)2. The results showed that the incorporation of boron into Mg(OH)2 was very rapid and reached the equilibrium after 4 h. The [B]s and the partition coefficient Kd between Mg(OH)2 and final solution decreased with the increasing pH. The maximum values of [B]s and Kd were much higher than that of boron adsorbed on metal oxide or clay minerals, indicating that the incorporation capability of boron into Mg(OH)2 was very strong. When the adsorption reached the equilibrium, the δ 11Bfsw was lower than δ 11Bisw. The boron isotopic fractionation αs-fsw was between 1.0186 and 1.0220 with an average of 1.0203. All these indicated that 11B incorporated into Mg(OH)2 preferentially due to B(OH)3 incorporation into Mg(OH)2 preferentially. The deposition reaction of B(OH)3 with Mg(OH)2 was the direct reason for B(OH)3 incorporation into Mg(OH)2. During the boron incorporation into Mg(OH)2, the isotopic fractionation characteristic of boron was decided by the simultaneous existence of adsorption of boron on Mg(OH)2 and the deposition reaction of H3BO3 with Mg(OH)2. Different from the fact that only B(OH)4-species incorporated into bio-carbonate, B(OH)3 and B(OH)4 incorporated into Mg(OH)2 simultaneously, and B(OH)3 incorporated into it preferentially. The lower pH is, the more incorporated fraction of B(OH)3 will be. Mg(OH)2 exists widely in madrepore, which influences the quantitative correspondence of the boron isotopic composition δ 11Bcarb of corals on the pH of the seawater badly, and brings serious uncertainty to the δ 11Bcarb as the indicator of the ancient seawater pH. | XIAO Jun XIAO YingKai LIU CongQiang ZHAO ZhiQi HE MaoYong LIANG ChongShan | 2009 | Chinese Science Bulletin2009，54，17： | 7 |
| 2 | Stable isotope fractionation of chlorine during evaporation of brine from a saline lake显示文摘Brine from the saline Qarhan Lake was evaporated at 28±2°C in a clean environment.Two groups of experiments were conducted;one with complete separation of precipitate and brine at different stages of evaporation,and the other with continuous precipitation during the evaporation.Seventy-nine precipitate and brine samples were collected during the experiments,and the δ37 Cl values were determined using an improved thermal ionization mass spectrometry procedure for precise measurement of chlorine isotopes based on Cs2Cl+ ions.Based on the concentrations of Na+,K+,and Mg2+,evaporation was divided into three main precipitation stages as follows:halite dominant,carnallite dominant,and bischofite dominant.The δ37 Clsolid and δ37 Clliquid values of the precipitate and coexisting brine samples at different stages showed the following characteristics.The precipitates were enriched with 37 Cl relative to the coexisting brine samples,and the δ37 Cl of both the precipitate and brine samples decreased gradually during evaporation.The fractionation factors(αh) between halite and brine were the highest,followed by that(αc) between carnallite and brine,and then that(αb) between bischofite and brine.The αc and αb values of less than one,which indicate the precipitate is enriched in 35 Cl,were found when the evaporation process entered a new stage.However,the δ37 Cl values of carnallite,bischofite,and the coexisting brine samples decreased during evaporation.The residual brine is a 35 Cl reservoir.The experimental phenomena were consistent with the δ37 Cl values in saline deposits in the literature.δ37 Cl can be used as an indicator of brine evaporation processes,which is important in the exploration of sylvinite deposits. | LUO ChongGuang XIAO YingKai MA HaiZhou MA YunQi ZHANG YanLing HE MaoYong | 2012 | Chinese Science Bulletin2012，57，15： | 6 |
| 3 | Effects of environmental contaminants on fertility and reproductive health显示文摘Recent research indicates that the human infertility rate is increasing. Although various reasons have been hypothesized for the growing infertility rate, environmental contaminants are potentially important causal agents associated with this change.Chemical contaminants are widespread throughout our environment and human exposure is virtually unavoidable. The overall contribution of environmental exposure to infertility is unknown, but studies involving occupational exposure, together with results from animal experiments, suggest that environmental contaminants may adversely affect fertility. We reviewed the adverse effects of environmental exposure on fertility and related reproductive outcomes. Environmental contaminants covered in this review include heavy metals, organic solvents, pesticides and endocrine disrupting chemicals. It is hoped that this review will highlight the need for further research in this area. | Yanmin Ma Xin He Keyan Qi Tong Wang Yongchao Qi Lele Cui Fengbang Wang Maoyong Song | 2019 | Journal of Environmental Sciences2019，31，3： | 6 |
| 4 | The nonmarine environment of Quaternary foraminifers in Yanghuzhuang, China: Evidence from boron and strontium isotopes显示文摘The concentrations and isotopic compositions of boron and strontium of Quaternary foraminifers and bivalve fossils collected in the Yanghuzhuang section of Yanqing, Beijing and of modern gastropods living in the Guishui River and of river water were measured. The concentrations and isotopic compo- sitions of Quaternary foraminifers and bivalve fossils differed from those of modern marine fo- raminifers and were similar to those of modern terrestrial gastropods from the Guishui River. These results indicate that early Quaternary foraminifers in the Yanghuzhuang section inhabited a nonmarine environment and that these foraminifers were not the result of a transgression or sea flooding. The foraminifers were not special halobios and can survive in the terrestrial condition that resembled those of the ocean. | XIAO YingKai XIAO Jun ZHAO ZhiQi HE MaoYong LI ShiZhen | 2008 | Chinese Science Bulletin2008，53，14： | 3 |
| 5 | Sample preparation for isotopic determination of boron in clay sediments显示文摘The procedures of sample preparation for isotopic determination of boron in clay sediments is very cumbersome, by far, there haven't been relevant reports on that. In order to establish an effective method for sample preparation, a series of experiments were carried out. In this paper, boron in clay sediments was extracted with HCl solution and purified by two-step ion exchange method. Extracted HCl solution should be adjusted to alkalescency before passing through the Amberlite IRA 743 resin column due to the fact that Amberlite IRA 743 resin absorbs boron only from alkalescent solution. However, a mass of hydroxides of Al and Fe will be precipitated when the extracted HCl solution becomes alkalescent. Hydroxides of Al and Fe have a strong adsorption capacity for boron, which can cause boron isotope fractionation. To treat precipitated hydroxides of Al and Fe, four procedures, namely direct ion exchange (DRIE), decationizing ion exchange (DCIE), once sedimentation ion exchange (OSIE) and repeated sedimentation ion exchange (RSIE) were used and assessed. The influences of the four procedures on separation and extraction and isotopic composition of boron in experimental solutions and clay sediments were also discussed. According to the results, the DRIE, DCIE and OSIE are improper. The result of sample determination indicates that when extracting boron via RSIE, with the increase of precipitation times, there's an obvious decrease in boron content in the precipitated hydroxides while a sharp increase in recovery of boron and it is favorable for weakening the influence of boron isotope fractionation. But the process of RSIE is time consuming and it may introduce boron. It needs further research to establish a more effective sample preparation method for isotopic deter- mination of boron in clay sediments. | ZHANG Yanling XIAO Yingkai MA Yunqi ZHUGE Qin LIU Zhiqi HE Maoyong LUO Chongguang MA Haizhou | 2013 | Chinese Journal Of Geochemistry2013，32，2： | 2 |
| 6 | Correlation between δ^(18)O, Sr/Ca and Mg/Ca of coral Acropora and seawater temperature from coral culture experiments显示文摘To be used as proxies of seawater surface temperature(SST), the δ 18Oc values and Sr/Ca and Mg/Ca ratios of scleractinian coral skeletons must be verified by coral culture experiments in the laboratory. This paper describes a coral culture experiment that was conducted at several seawater temperatures T(21–28°C) using a tandem aquarium system and the new method for depositing coral skeletons grown under controlled conditions. The δ 18Oc values and the Sr/Ca and Mg/Ca ratios of the cultured coral were measured. We concluded that the δ 18Oc values and Sr/Ca and Mg/Ca ratios of the cultured coral are clearly correlated with T. The linear regression curve is δ18Oc(‰)=δ0.1427δT(°C)δ0.1495(n=18, r=0.955, p<0.0001), and the slope of δ0.1427‰/°C is at the low end of the range of published values(δ0.13–δ0.29‰/°C). The Sr/Ca ratio decreases with increasing T, whereas the Mg/Ca ratio increases with increasing T, indicating a negative correlation between Sr/Ca and Mg/Ca. Their linear regression curves are Sr/Ca(mmol/mol)=δ0.04156δT+10.59(n=15, r=0.789, p<0.005) and Mg/Ca(mmol/mol)= 0.04974δT+2.339(n=17, r=0.457, p<0.05), respectively, which demonstrate that when Mg/Ca and Sr/Ca are increased by one unit, T increases by 5.19°C and decreases by 15.62°C, respectively. These variations are significantly lower than published values. | XIAO YingKai LIU WeiGuo MA YunQi ZHANG YanLing HE MaoYong LUO ChongGuang LIAO QingQiang | 2014 | Science China Earth Sciences2014，57，5： | 1 |
| 7 | Leachate Lithium Characteristics of Loess-paleosol Sequences on the Chinese Loess Plateau and their Paleoclimatic Significance显示文摘The geochemical components of the leachate from loess-paleosol deposits can provide information about climaterelated post-depositional processes.For example,leachate lithium([Li]_(leachate))is a potential paleoclimate proxy because lithium is a typical lithophile element that is readily adsorbed by clay minerals during weathering and pedogenesis,and thus stratigraphic variations in[Li]leachatecan reflect these processes.We investigated the[Li]leachatevalues of two loess-paleosols profiles(the Luochuan and Weinan sections),on a north-south climatic gradient on the Chinese Loess Plateau.Independent paleoclimate information was provided by measurements of magnetic susceptibility,grain size,Rb/Sr ratios,and clay mineral content.During the last glacial-interglacial period,[Li]leachateincreased from 0.39 to 1.97μg/g at Luochuan and from 0.67 to 2.45μg/g at Weinan,mainly due to increasing pedogenesis.Based on these results we developed a conceptual model to explain the variations in[Li]leachate,Li^(+)within loess layers is mainly derived from dust input and the decomposition of primary minerals,influenced by the East Asian winter monsoon,while in paleosol layers Li is mainly derived from clay mineral adsorption during pedogenic processes,influenced by the East Asian summer monsoon. | JIA Peng FU Chaofeng HE Maoyong LIU Junfeng LIU Na LI Yulong YANG Kaiyuan | 2023 | Acta Geologica Sinica(English Edition)2023，97，6： | 0 |
| 8 | Boron isotopic composition of Paleozoic brachiopod and coeval coral calcites in Yunnan-Guizhou Plateau, China显示文摘Boron isotope values in Paleozoic brachiopods and corals, collected from the Yunnan-Guizhou Plateau, China, can be used to constrain the boron isotope compositions of past oceans. All brachiopod shells and coral samples were screened for diagenetic recrystallization by cathodoluminescence microscopy, trace element geochemistry of B, Fe, Mn, Sr, and scanning electron microscopy. The boron isotope ratios for brachiopods in Silurian, Devonian, Carboniferous, and Triassic calcites are in the ranges 8.9‰-14.0‰, 8.8‰-13.8‰, 10.3‰-16.3‰, and 6.7‰-12.4‰, respectively. The boron isotope ratios of coral calcites in the Silurian, Devonian, and Permian are 9.1‰-12.2‰, 6.1‰-13.8‰, and 9.2‰-16.1‰, respectively. The δ11B values for both brachiopods and corals are significantly lower than those for modern biogenic carbonates, indicating that the Paleozoic oceans were depleted of δ11B by up to 10‰. Our results are consistent with previous published studies. The boron isotope compositions of corals and brachiopods show the consistent trends. The low δ11B values may be explained by an enhanced riverine flux of boron from the continents. | MA YunQi XIAO YingKai HE MaoYong XIAO Jun SHEN Quan JIANG ShengXiang | 2011 | Science China Earth Sciences2011，54，12： | 0 |
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