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| 1 | Mapping wetland changes in China between 1978 and 2008显示文摘Four wetland maps for all China have been produced,based on Landsat and CBERS-02B remote sensing data between 1978 and 2008 (1978,1990,2000 and 2008).These maps were mainly developed by manual interpretation and validated by substantial field investigation in 2009.Based on these maps,we analyzed the 2008 wetland distribution in China and discussed wetland changes and their drivers over the past 30 years.(i) There were about 324097 km 2 of wetlands in 2008,for which inland marshes or swamps were the most common wetland type (35%),with lakes (26%) second.Most of the wetlands were in Heilongjiang,Inner Mongolia,Qinghai and Tibet,occupying about 55% of the national wetland area.(ii) From 1978 to 2008,China's wetland area continually and significantly decreased,by about 33% based on changes in the wetland map.This was in sharp contrast to the increase in artificial wetlands,which increased by about 122%.Inland marshes accounted for the main loss of total wetlands from 1978 to 2000.From 2000 through 2008,riverine and lacustrine wetlands constituted the main wetland loss.Fortunately however,the rate of wetland loss decreased from 5523 to 831 km 2 /a.(iii) The change ratio of lost natural wetlands (including inland and coastal wetlands) to non-wetlands has decreased slightly over the past 30 years.From 1978 to 1990,nearly all natural wetlands (98%) lost were transformed into non-wetlands.However,the ratio declined to 86% from 1990 to 2000,and to 77% from 2000 to 2008.(iv) All Chinese provinces were divided into three groups according to patterns of wetland changes,which could relate to the driving forces of such changes.Tibet was completely different from other provinces,as it was one representative example in which there was a net wetland increase,because of global warming and decreased human activity since 1990.Increased economic development caused considerable wetland loss in most eastern provinces,and artificial wetlands increased. | NIU ZhenGuo ZHANG HaiYing WANG XianWei YAO WenBo ZHOU DeMin ZHAO KuiYi ZHAO Hui LI NaNa HUANG HuaBing LI CongCong YANG Jun LIU CaiXia LIU Shuang WANG Lin LI Zhan YANG ZhenZhong QIAO Fei ZHENG YaoMin CHEN YanLei SHENG YongWei GAO XiaoHong ZHU WeiHong WANG WenQing WANG Hong WENG YongLing ZHUANG DaFang LIU JiYuan LUO ZhiCai CHENG Xiao GUO ZiQi GONG Peng | 2012 | Chinese Science Bulletin2012，57，22： | 51 |
| 2 | Millennial temperature reconstruction based on tree-ring widths of Qilian juniper from Wulan,Qinghai Province,China显示文摘The climate of the past 1000 years is an important context for evaluating the recent climate warming.However,there are few 1000-year-long climate reconstructions with annual resolution in the Qing-hai-Tibet Plateau.In this paper,a dendroclimatic analysis was conducted for the radial growth of Qilian juniper from the upper forest limit in Wulan,Qinghai Province.The results of correlation analysis between the tree-ring widths and the climate variables indicate that the growth of junipers at the upper forest limit is mainly limited by low temperatures of September,November and February of the pregrowth season,and July of the current growth season.There is no significant correlation between the tree-ring widths and precipitation.A mean temperature from the previous year's September to the current year's April was reconstructed for the Wulan area since A.D.1000.The reconstruction can explain 40.8% of the instrumental variance in the calibration period(1856―2002).The reconstruction shows that the 20th century is the warmest 100 years,and the 1990s is the warmest decade during the past 1000 years,while the coldest 100 years and decade occur at 1600―1699 and 1642―1651,respectively.The variations are verified well by the temperature reconstruction of the middle Qilian Mountain(QL) and the total organic carbon(TOC) in the Qinghai Lake sediments.The comparison of our reconstruction with the annual temperature reconstruction of extra-tropical Northern Hemisphere suggests that the climate of Wulan during the Medieval Warm Period is of obvious regional specialty,but there was a good response to the climate of hemispheric scales during the recent 400 years. | ZHU HaiFeng ZHENG YongHong SHAO XueMei LIU XiaoHong XU Yan LIANG ErYuan | 2008 | Chinese Science Bulletin2008，53，24： | 40 |
| 3 | Level of circulating PD-L1 expression in patients with advanced gastric cancer and its clinical implications显示文摘Objective:The programmed cell death-1 receptor/programmed cell death-1 ligand(PD-1/PD-L1) pathway plays a crucial role in tumor evasion from host immunity.This study was designed to evaluate the association between circulating PD-L1 expression and prognosis in patients with advanced gastric cancer.Methods:Totally 80 advanced gastric cancer patients and 40 health controls from Beijing Cancer Hospital were enrolled in the present study.Circulating PD-L1 expression was tested by enzymelinked immunosorbent assay(ELISA).The associations between the expression level of PD-L1 and clinicopathological features and prognosis were analyzed statistically.Results:Expression of PD-L1 in advanced gastric cancer patients was significantly up-regulated compared with health people(P=0.006).The expression of PD-L1 was significantly correlated with differentiation and lymph node metastasis(P=0.026 and P=0.041,respectively).Although we didn't find significant difference in all advanced gastric cancer patients with different PD-L1 expression,the adenocarcinoma patients with higher up-regulated PD-L1 expression had much better prognosis than low expression patients(65.6% vs.44.7%,P=0.028).Conclusions:PD-L1 was elevated in advance gastric cancer patients and may play an important role in tumor immune evasion and patients prognosis. | Zhixue Zheng Zhaode Bu Xijuan Liu Lianhai Zhang Ziyu Li Aiwen Wu Xiaojiang Wu Xiaojing Cheng Xiaofang Xing Hong Du Xiaohong Wang Ying Hu Jiafu Ji | 2014 | Chinese Journal of Cancer Research2014，26，1： | 37 |
| 4 | Effect of SiC whiskers on the oxidation protective properties of SiC coatings for carbon/carbon composites显示文摘以便有效地采用唯一的高温度碳 / 碳的机械性质合成底层,原文如此,涂层增强了由原文如此,络腮胡子被包装硬化方法准备。效果原文如此,单个层的涂层和双层涂层的氧化抵抗性质上的络腮胡子被调查。原文如此络腮胡子在单个层原文如此涂层在反氧化性质上有小效果,但是显然改进热吃惊性质。有内部层的增强的涂层的双层涂层与原文如此内部层的涂层比双层涂层展出更多的完美的反氧化能力。 | SHI Xiaohong LI Hejun FU Qiangang LI Kezhi ZHANG Xiulian | 2006 | Rare Metals2006，25，1： | 33 |
| 5 | A method for gravity anomaly separation based on preferential continuation and its application显示文摘基于 Pawlowski (1995 ) 建议的优先的继续方法,我们在各种各样的来源互相是 uncorrelated 与,继续高度足够大的情况中与优先的向上的继续操作员为严肃异例分离建议一个方法和过程。我们也为估计最佳介绍一个方法向上继续的高度,与不同继续高度基于分析一个综合严肃异例的优先的向上的继续操作员的特征变化。方法在铁存款上在未加工的 Bouguer 严肃数据上被测试。结果证明方法高效地并且清楚地把数据分开成地区性的异例和剩余异例。 | Meng Xiaohong Guo Lianghui Chen Zhaox Li Shuling Shi Lei | 2009 | Applied Geophysics2009，6，3： | 31 |
| 6 | Forming age and tectono-petrogenises of the Jiugequan ophiolite in the North Qilian Mountain,NW China显示文摘The Jiugequan ophiolite is one of the representative ophiolite fragments in the Early Paleozoic orogenic belt of the North Qilian Mountain.It has been drawn much attention and extensively studied in recent years.In this study,ion microprobe(SHRIMP) U-Pb dating was carried out for zircons from isotropic gabbro from the Jiugequan ophiolite.Eighteen analyses yield a relatively consistent apparent 206Pb/238U ages from 480 to 508 Ma with a weighted mean age of 490±5 Ma(MSWD=1.06),which is believed to be the crystallization age of the gabbro and thus the forming age of the Jiugequan ophiolite.Major and trace element geochemical study indicates that the diabase-basalts from the Jiugequan ophiolite have N-MORB and E-MORB characteristics with some subduction-related signatures.The petrological,geochemical and chronological data enable us to conclude that the Jiugequan ophiolite is most likely to be formed at a spreading center of back-arc basin during the early Ordovician,while the ancient Qilian oceanic plate subducted northwards.The acquisition of forming age and determination of tectonic setting for Jiugequan ophiolite provide significant constraints on the evolution of intra-oceanic subduction system in the North Qilian orogenic belt during the Early Paleozoic era. | XIA XiaoHong SONG ShuGuang | 2010 | Chinese Science Bulletin2010，55，18： | 33 |
| 7 | Nutrient concentration variations during Oenanthe javanica growth and decay in the ecological floating bed system显示文摘The ecological floating bed system is a natural alternative to technical methods of wastewater treatment and involves complex processes induced by plants or microorganisms in the wastewater. This study aimed to identify nutrient concentration variations during Oenanthe javanica (Blume) DC growth and decay in the ecological floating bed system. Results showed that the third-order polynomial equation was suitable to describe pollutant concentration changes, showing that the effect of O. javanica ecological floating bed system on polluted water could be divided into the purification phase and decay phase. During the purification phase, nutrient concentrations rapidly decreased because O. javanica influenced water microbial communities and water physical parameters (i.e., dissolved oxygen, pH, and temperature), and had a direct uptake of nutrients. However, during the decay phase, nitrogen and phosphorus concentrations in the plant tissues decreased, and these lost nutrients ultimately transferred to water and led to water quality deterioration. Results also showed that the uptake and storage of O. javanica in nutrients were temporary and the plant served only as media of the nutrients removed from the water. Under these circumstances, harvesting was an appropriate intervention to improve the treatment efficiency of O. javanica ecological floating bed system. | Xiaohong Zhou Guoxiang Wang | 2010 | Journal of Environmental Sciences2010，22，11： | 31 |
| 8 | A Mini-Review on Metal Recycling from Spent Lithium Ion Batteries显示文摘 | Xiaohong Zheng Zewen Zhu Xiao Lin Yi Zhang Yi He Hongbin Cao Zhi Sun | 2018 | Engineering2018，4，3： | 33 |
| 9 | Clinical observation on effect of scalp electroacupuncture for mild cognitive impairment显示文摘OBJECTIVE: To evaluate the therapeutic effect of scalp electroacupuncture for mild cognitive impairment (MCI) in the early stage. METHODS: Two hundred and thirty three MCI patients were randomly divided into three groups: the drug group, the scalp electroacupuncture group, and the syndrome differentiation group. For the scalp electroacupuncture group, the points of Baihui (DU 20), Sishecong (EX-HN1), Fengchi (GB 20), and Shenting (DU 24) were selected. For the syndrome differentiation group, specific acupoints were added on the basis of syndrome differentiation and according to the scale for the differentiation of syndromes in vascular dementia (SDSVD) beside the acupoints used in the scalp electroacupuncture group. For the drug group, nimodipine was orally administered. Each patient was treated for two courses, eight weeks. The score differences in minimental state examination (MMSE), picture recognition, and clock drawing test were observed before and after the treatment. RESULTS: After treatment, the score differences in MMSE and clock drawing test were of obvious statistical significance among three groups (P<0.01, P<0.05). The score differences in picture recognition were of extremely statistical significance between the scalp electroacupuncture group and the syndrome differentiation group (P<0.01), while the difference was not found in the drug group (P>0.05). There were statistical significant differences in therapeutic effects between the scalp electroacupuncture group and the drug group, and between the syndrome differentiation group and the drug group (P<0.05), while no statistical difference was found between scalp electroacupuncture group and the syndrome differentiation group (P>0.05). CONCLUSION: All the three therapies may improve the cognitive function of MCI patients. The therapeutic effects in the scalp electroacupuncture and syndrome differentiation groups were basically the same, but superior to nimodipine. | Hong Zhang Ling Zhao Sha Yang Zhigang Chen Yingkun Li Xiaohong Peng Yulong Yang Manjia Zhu | 2013 | Journal of Traditional Chinese Medicine2013，33，1： | 23 |
| 10 | Ten cities cross-sectional questionnaire survey of children asthma and other allergies in China显示文摘Asthma,rhinitis and eczema(allergic or non-allergic)have increased throughout the world during the last decades,especially among children.Changes in the indoor environment are suspected to be important causes.China has experienced a dramatic change in indoor environmental exposures during the past two decades.However,such changes and their associations with children’s asthma and other health aspects have not been thoroughly studied.China,Children,Homes,Health(CCHH),Phase I,was a cross-sectional questionnaire survey of 48219 children 1–8 years old in 10 Chinese cities during 2010–2012.The questionnaire includes the International Study of Asthma and Allergies in Childhood(ISAAC)core health questions and additional questions regarding housing,life habits and outdoor environment.In health analyses,children aged 3–6 years old were included.The prevalences of doctor diagnosed asthma varied from 1.7%to 9.8%(mean 6.8%),a large increase from 0.91%in 1999 and 1.50%in2000.The prevalence of wheeze,rhinitis and atopic eczema(last 12 months)varied from 13.9%to 23.7%,24.0%to 50.8%and4.8%to 15.8%,respectively.Taiyuan had the lowest prevalences of all illnesses and Shanghai the highest,except for wheezewhere the highest value was for Urumqi.We found(1)no obvious association between disease prevalences and ambient PM10concentrations and(2)higher prevalences of disease in humid climates with hot summers and cold winters,but with no centrally heated buildings.Associations between the diseases and economic status as indexed by Gross Domestic Product(GDP)requires further study. | ZHANG YinPing LI BaiZhan HUANG Chen YANG Xu QIAN Hua DENG QiHong ZHAO ZhuoHui LI AnGui ZHAO JiaNing ZHANG Xin QU Fang HU Yu YANG Qin WANG Juan ZHANG Ming WANG Fang ZHENG XiaoHong LU Chan LIU ZhiJian SUN YueXia MO JinHan ZHAO YiLi LIU Wei WANG TingTing NORBCK Dan BORNEHAG Carl-Gustaf SUNDELL Jan | 2013 | Chinese Science Bulletin2013，58，34： | 22 |
| 11 | Blockade of Tim-3 Pathway Ameliorates Interferon-γ Production from Hepatic CD8^+ T Cells in a Mouse Model of Hepatitis B Virus Infection显示文摘T cell immunoglobulin-and mucin-domain-containing molecule-3(Tim-3) has been reported to participate in the pathogenesis of inflammatory diseases. However,whether Tim-3 is involved in hepatitis B virus(HBV) infection remains unknown. Here,we studied the expression and function of Tim-3 in a hydrodynamics-based mouse model of HBV infection. A significant increase of Tim-3 expression on hepatic T lymphocytes,especially on CD8+ T cells,was demonstrated in HBV model mice from day 7 to day 18. After Tim-3 knockdown by specific shRNAs,significantly increased IFN-γ production from hepatic CD8+ T cells in HBV model mice was observed. Very interestingly,we found Tim-3 expression on CD8+ T cells was higher in HBV model mice with higher serum anti-HBs production. Moreover,Tim-3 knockdown influenced anti-HBs production in vivo. Collectively,our data suggested that Tim-3 might act as a potent regulator of antiviral T-cell responses in HBV infection. | Ying Ju Nan Hou Xiaoning Zhang Di Zhao Ying Liu Jinjin Wang Fang Luan Wei Shi Faliang Zhu Wensheng Sun Lining Zhang Chengjiang Gao Lifen Gao Xiaohong Liang Chunhong Ma | 2009 | Cellular & Molecular Immunology2009，6，1： | 19 |
| 12 | Interactive effects of wind speed,vegetation coverage and soil moisture in controlling wind erosion in a temperate desert steppe,Inner Mongolia of China显示文摘The rapid desertification of grasslands in Inner Mongolia of China poses a significant ecological threaten to northern China. The combined effects of anthropogenic disturbances(e.g., overgrazing) and biophysical processes(e.g., soil erosion) have led to vegetation degradation and the consequent acceleration of regional desertification. Thus, mitigating the accelerated wind erosion, a cause and effect of grassland desertification, is critical for the sustainable management of grasslands. Here, a combination of mobile wind tunnel experiments and wind erosion model was used to explore the effects of different levels of vegetation coverage, soil moisture and wind speed on wind erosion at different positions of a slope inside an enclosed desert steppe in the Xilamuren grassland of Inner Mongolia. The results indicated a significant spatial difference in wind erosion intensities depending on the vegetation coverage, with a strong decreasing trend from the top to the base of the slope. Increasing vegetation coverage resulted in a rapid decrease in wind erosion as explained by a power function correlation. Vegetation coverage was found to be a dominant control on wind erosion by increasing the surface roughness and by lowering the threshold wind velocity for erosion. The critical vegetation coverage required for effectively controlling wind erosion was found to be higher than 60%. Further, the wind erosion rates were negatively correlated with surface soil moisture and the mass flux in aeolian sand transport increased with increasing wind speed. We developed a mathematical model of wind erosion based on the results of an orthogonal array design. The results from the model simulation indicated that the standardized regression coefficients of the main effects of the three factors(vegetation coverage, soil moisture and wind speed) on the mass flux in aeolian sand transport were in the following order: wind speed>vegetation coverage>soil moisture. These three factors had different levels of interactive effects on the mass flux in aeolian sand transport. Our results will improve the understanding of the interactive effects of wind speed, vegetation coverage and soil moisture in controlling wind erosion in desert steppes, and will be helpful for the design of desertification control programs in future. | MENG Zhongju DANG Xiaohong GAO Yong REN Xiaomeng DING Yanlong WANG Meng | 2018 | Journal of Arid Land2018，10，4： | 19 |
| 13 | BDS triple-frequency carrier-phase linear combination models and their characteristics显示文摘An investigation has been made on the models and characteristics of triple-frequency carrier-phase linear combinations for the Bei Dou Navigation Satellite System(BDS). Based on the three frequencies of the BDS, three categories of combinations are developed: ionosphere-free combinations(i.e., those that eliminate the ionospheric effect), minimum-noise combinations(those that mitigate the effects of thermal noise and multiple paths), and troposphere-free combinations(those that mitigate tropospheric effects). Both the ionosphere-free and troposphere-free combinations can be expressed as planes, whereas the minimum-noise combinations can be expressed as a line. The relationships between these three categories of linear combinations are investigated from the perspective of geometry. The angle between the troposphere-free plane and ionosphere-free plane is small, while the angles between the troposphere-free plane and the minimum-noise line, and between the ionosphere-free plane and the minimum-noise line, are large. Specifically, the troposphere-free plane is orthogonal to the minimum-noise line. By introducing the concepts of lane number and integer ionosphere number, the characteristics of the long-wavelength integer combinations and ionosphere-free integer combinations are investigated. The analysis indicates that the longest wavelength that can be formed for integer combinations is 146.53 m, and the ionosphere-free integer combinations all have large noise amplification factors. The ionosphere-free integer combination with minimum noise amplification factor is(0, 62, 59). According to the lane number, integer ionosphere number, and noise amplification factor, optimal integer combinations with different characteristics are presented. For general short baselines and long baselines, three independent integer combinations are suggested. | ZHANG XiaoHong HE XiYang | 2015 | Science China Earth Sciences2015，58，6： | 18 |
| 14 | The Impact of the Linked Factors of Provenance,Tectonics and Climate on Potash Formation:An Example from the Potash Deposits of Lop Nur Depression in Tarim Basin,Xinjiang,Western China显示文摘Potash deposits commonly accumulate in highly restricted settings at the final stage of brine evaporation. This does not mean that potash deposits are formed simply as a result of the evaporation concentration of seawater or lake water, but rather as a coupling result of particular provenance, tectonics and climate activities. In this paper, we focus on the formative mechanism of the potash deposits of Lop Nur depression in Tarim Basin to interpret the detailed coupling mechanism among provenance, tectonics and climate. In terms of the provenance of Lop Nur Lake, the water of the Tarim River which displays 'potassium-rich' characteristics play an important role. In addition, the Pliocene and Lower-Middle Pleistocene clastic beds surrounding Lop Nur Lake host a certain amount of soluble potassium and thus serves as 'source beds' for potash formation. During the late Pliocene, the Lop Nur region has declined and evolved into a great lake from the previous piedmont and diluvial fan area. Since the mid Pleistocene, the great-united Lop Nur Lake has been separated and has generated a chain system consisting of Taitema Lake, Big Ear Lake and Luobei Lake which has turned into the deepest sag in Lop Nur Lake. Dry climate in Lop Nur region has increased since the Pliocene, and became extreme at the late Pleistocene. The study implies that potash formation in Lop Nur Lake depends on the optimal combination of extreme components of provenance, tectonics and climate during a shorter-term period. The optimal patterns of three factors are generally characterized by the long-term accumulation and preliminary enrichment of potassium, the occurrence of the deepest sub-depression and the appearance of an extremely arid climate in Lop Nur region. These factors have been interacting synergistically since the forming of the saline lake and in the later stages strong 'vapor extraction' caused by extremely arid climate is needed to trigger large scale mineralization of potash deposits. | LIU Chenglin JIAO Pengcheng Lü Fenglin WANG Yongzhi SUN Xiaohong ZHANG Hua WANG Licheng YAO Fojun | 2015 | Acta Geologica Sinica(English Edition)2015，89，6： | 18 |
| 15 | A detailed procedure for CRISPR/Cas9-mediated gene editing in Arabidopsis thaliana显示文摘The newly developed CRISPR(Clustered Regularly Interspaced Short Palindromic Repeats)/Cas(CRISPR-associated) system has emerged as an efficient tool for genome-editing, providing an alternative to classical mutagenesis and transgenic methods to study gene function and improve crop traits. CRISPR/Cas facilitates targeted gene editing through RNA-guided DNA cleavage followed by cellular DNA repair mechanisms that introduce sequence changes at the site of cleavage. Here we describe a detailed procedure for our previously developed and highly efficient CRISPR/Cas9 method that allows the generation of heritable-targeted gene mutations andcorrections in Arabidopsis. This protocol describes the strategies and steps for the selection of targets, design of single-guide RNA(sg RNA), vector construction and analysis of transgenic lines. We also offer a method to target two loci simultaneously using vectors containing two different sg RNAs. The principles described in this protocol can be applied to other plant species to generate stably inherited DNA modifications. | Wenshan Liu Xiaohong Zhu Mingguang Lei Qingyou Xia Jose Ramon Botella Jian-Kang Zhu Yanfei Mao | 2015 | Science Bulletin2015，60，15： | 18 |
| 16 | LGR5 is a promising biomarker for patients with stage Ⅰ and Ⅱ gastric cancer显示文摘Objective: To investigate Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) expressions in gastric cancer and to evaluate its clinical significance. Methods: LGR5 expression was assessed by immunohistochemistry in 257 gastric cancer patients after surgery. The relationships between LGR5 expression and clinicopathological features and patients prognosis were statistically analyzed. Results: The expression of LGR5 was significantly higher in gastric cancers as a cancer stem cell marker than in adjacent normal tissues (P<0.001), and more frequently in patients with intestinal type, well-moderate differentiation and stage Ⅰ and Ⅱ (P<0.05). Although we found gastric cancer patients with LGR5 positive expression had a poorer prognosis, it didn't meet statistical significance (P>0.05). LGR5 negative expression was significantly related to the favorable overall survival in stage Ⅰ and Ⅱ gastric cancer patients (P<0.05). Furthermore, patients with high LGR5 expression tended to be more likely to get progression and have poorer progress-free survival (P<0.05). Multivariate Cox regression analysis revealed that LGR5 expression was an independent factor of overall survival for the patients with stage Ⅰ and Ⅱ gastric cancer (P<0.05). Conclusions: Our results show that LGR5 may play an important role in tumorigenesis and progression and would be a powerful marker to predict the prognosis of patients with stage Ⅰ and Ⅱ gastric cancer. | Zhaode Bu Zhixue Zheng Lianhai Zhang Ziyu Li Yu Sun Bin Dong Aiwen Wu Xiaojiang Wu Xiaohong Wang Xiaojing Cheng Xiaofang Xing Yingai Li Hong Du Jiafu Ji | 2013 | Chinese Journal of Cancer Research2013，25，1： | 17 |
| 17 | Electromechanical coupling driving control for single-shaft parallel hybrid powertrain显示文摘The single-shaft parallel hybrid powertrain with the automatic mechanical transmission(AMT)is an efficient hybrid driving system in the hybrid electric bus(HEB),while the electromechanical coupling driving control becomes a complicated question to find a transient optimal control method to distribute the power between the engine and the electric machine(EM).This paper proposes an innovative control method to deal with the complicated transient coupling driving process of the electromechanical coupling driving system,considering the accelerating condition and the cruising condition mostly in the city driving cycle of HEB.The EM might be operated at driving mode or generating mode to assist the diesel engine to work in its high-efficiency area.Therefore,the adaptive torque tracking controller has been brought forward to ensure that the EM implements the demand torque as well as compensate the torque fluctuation of diesel engine.The d?q axis mathematical model and back stepping method are employed to deduce the adaptive controller and its adaptive laws.Simulation results demonstrate that the proposed control scheme can make the output torque of two power sources respond rapidly to the demand torque from the powertrain in the given driving condition.The proposed method could be adopted in the real control of HEB to improve the efficiency of the hybrid driving system. | YANG Chao JIAO XiaoHong LI Liang ZHANG YaHui ZHANG LiPeng SONG Jian | 2014 | Science China(Technological Sciences)2014，57，3： | 17 |
| 18 | Simple and cost-effective methods for precise analysis of trace element abundances in geological materials with ICP-MS显示文摘Inductively coupled plasma mass spectrometry(ICP-MS) is the most commonly used technique to determine the abundances of trace elements in a wide range of geological materials. However, incomplete sample digestion, isobaric interferences and instrumental drift remain obvious problems that must be overcome in order to obtain precise and accurate results. For this reason, we have done many experiments and developed a set of simple, cost-effective and practical methods widely applicable for precise and rapid determination of trace element abundances in geological materials using ICP-MS. Commonly used high-pressure digestion technique is indeed effective in decomposing refractory phases, but this inevitably produces fluoride complexes that create new problems. We demonstrate that the fluoride complexes formed during high-pressure digestion can be readily re-dissolved using high-pressure vessel at 190 °C for only 2 h for 50 mg sample. In the case of isobaric interferences, although oxide(e.g., MO+/M+) and hydroxide(e.g., MOH+/M+) productivity is variable between runs, the(MO+/M+)/(Ce O+/Ce+)and(MOH+/M+)/(Ce O+/Ce+) ratios remain constant, making isobaric interference correction for all other elements of interest straightforward, for which we provide an easy-to-use off-line procedure. We also show that mass-time-intensity drift curve is smooth as recognized previously, for which the correction can be readily done by analyzing a quality-control(QC) solution and using off-line Excel VBA procedure without internal standards. With these methods, we can produce data in reasonable agreement with recommended values of international rock reference standards with a relative error of <8% and precision generally better than 5%. Importantly, compared to the widely used analytical practice, we can effectively save >60% of time(e.g., <24 h vs. >60 h). | Shuo Chen Xiaohong Wang Yaoling Niu Pu Sun Meng Duan Yuanyuan Xiao Pengyuan Guo Hongmei Gong Guodong Wang Qiqi Xue | 2017 | Science Bulletin2017，62，4： | 17 |
| 19 | Kinetics and corrosion products of aqueous nitrate reduction by iron powder without reaction conditions control显示文摘Although considerable research has been conducted on nitrate reduction by zero-valent iron powder (Fe0), these studies were mostly operated under anaerobic conditions with invariable pH that was unsuitable for practical application. Without reaction conditions (dissolved oxygen or reaction pH) control, this work aimed at subjecting the kinetics of denitrification by microscale Fe0 (160–200 mesh) to analysis the factors affecting the denitrification of nitrate and the composition of iron reductive products coating upon the iron surface. Results of the kinetics study have indicated that a higher initial concentration of nitrate would yield a greater reaction rate constant. The reduction rate of nitrate increased with increasing Fe0 dosage. The reaction can be described as a pseudo-first order reaction with respect to nitrate concentration or Fe0 dosage. Experimental results also suggested that nitrate reduction by microscale Fe0 without reaction condition control primarily was an acid-driven surface-mediated process, and the reaction order was 0.65 with respect to hydrogen ion concentration. The analyses of X-ray diffractometry and X-ray photoelectron spectroscopy indicated that a black coating, consisted of Fe2O3, Fe3O4 and FeO(OH), was formed on the surface of iron grains as an iron corrosion product when the system initial pH was lower than 5. The proportion of FeO(OH) increased as reaction time went on, whereas the proportion of Fe3O4 decreased. | FAN Xiaomeng GUAN Xiaohong MA Jun AI Hengyu | 2009 | Journal of Environmental Sciences2009，21，8： | 17 |
| 20 | Laser probe ^(40)Ar/^(39)Ar dating of mica on the deformed rocks from Altyn Fault and its tectonic implications,western China显示文摘The samples of Caledonian mylonitized granite and Jurassic meta-sedimentary rocks were collected in the north of Dangjinshan Pass, Qaidam gate fault-valley and Gesi fault-valley. Detailed studies under the microscope and electronic microscope suggest that all the samples contain the syntectonic-growing minerals such as white mica, chlorite, sericite, biotite, etc. By dating these minerals, we got a group of 40Ar/39Ar laser probe isochronal ages of 89-92 Ma and apparent ages of (46.6±6.4) Ma. The ages ranging from 97 to 46 Ma were reported for the first time in the isotopic dating researches of the Altyn Fault The isochronal age group of (98-89) Ma indicates that a ductile strike-slip event, with low-grade metamorphism, began in late Cretaceous. This suggests that the strike-slip movement of the Altyn Fault should be related to the formation of the so-called west tectonic syntaxis in the Nepal-western Kunlun area. | LIU Yongjiang, YE Huiwen, GE Xiaohong, CHEN Wen, LIU Junlai, REN Shoumai & PAN HongxunCollege of Earth Sciences, Changchun University of Science and Technology, Changchun 130061, China Graduate School, China University of Geosciences, Beijing 100083, China Laboratory of Isotopic Geochronology, Institute of Geology, Ministry of Land and Resources of China, Beijing 100037, China | 2001 | Chinese Science Bulletin2001，46，4： | 16 |
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