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1Effects of water management on arsenic and cadmium speciation and accumulation in an upland rice cultivar显示文摘Pot and field experiments were conducted to investigate the effects of water regimes on the speciation and accumulation of arsenic(As) and cadmium(Cd) in Brazilian upland rice growing in soils polluted with both As and Cd. In the pot experiment constant and intermittent flooding treatments gave 3–16 times higher As concentrations in soil solution than did aerobic conditions but Cd showed the opposite trend. Compared to arsenate, there were more marked changes in the arsenite concentrations in the soil solution as water management shifted, and therefore arsenite concentrations dominated the As speciation and bioavailability in the soil. In the field experiment As concentrations in the rice grains increased from 0.14 to 0.21 mg/kg while Cd concentrations decreased from 0.21 to 0.02 mg/kg with increasing irrigation ranging from aerobic to constantly flooding conditions. Among the various water regimes the conventional irrigation treatment produced the highest rice grain yield of 6.29 tons/ha. The As speciation analysis reveals that the accumulation of dimethylarsinic acid(from 11.3% to 61.7%) made a greater contribution to the increase in total As in brown rice in the intermittent and constant flooding treatments compared to the intermittent-aerobic treatment. Thus, water management exerted opposite effects on Cd and As speciation and bioavailability in the soil and consequently on their accumulation in the upland rice. Special care is required when irrigation regime methods are employed to mitigate the accumulation of metal(loid)s in the grain of rice grown in soils polluted with both As and Cd.Pengjie Hu Younan Ouyang Longhua Wu Libo Shen Yongming Luo Peter Christie 2015Journal of Environmental Sciences2015,27,1:43
2Effects of Chinese Jianpi herbs on cell apoptosis and related gene expression in human gastric cancer grafted onto nude mice显示文摘AIM: To explore the mechanism of the Sijunzi decoction and another Chinese herbal recipe (SRRS) based mainly on the Sijunzi decoction in treatment of gastric cancer.METHODS: A human gastric adenocarcinoma cell line SGC7901 grafted onto nude mouse was used as the animal model. The mice were divided into 3 groups, one control and the two representative experimental conditions. Ahimals in the two experimental groups received either Sijunzi decoction or SRRS over a 40-day period starting at 1st day after grafting. Control animals received saline on an identical schedule. Animals were killed 41 days after being grafted.The effect of therapy was assessed by two ways: (1)tumor size was periodically measured during the life of the animals; (2) tumor weight was determined by a electron balance immediately after the animals killed. For detection of apoptotic cells, apoptotic indices(AI) were examined by the terminal deoxynucleotidyl transferase-mediated deoxyuddine tdphosphate fluorescence nick end labeling (TUNEL) method.Morphological alterations were observed with electron microscopy. S-P immunohistochemical method was used to detect the expression of Ki-67 in xenografts. Expression of bcl-2 and p53 was semiquantitatively detected using a reverse transcriptase-polymerase chain reaction (RT-PCR)technique.RESULTS: When compared with controls, tumor growth (size and weight) was significantly inhibited by treatment with the Sijunzi decoction (P<0.05) or SRRS (P<0.01). The tumor inhibitory rate in the Sijunzi decoction group was 34.33 % and SRRS group 46.53 %. AI of human gastric cancer xenografts in nude mice was significantly increased to 16.24±3.21% using TUNEL method and 11.38±6.46 % by FACScan in the Sijunzi decoction group compared with the controls (TUNEL: 2.63±1.03 %, P<0.01; FACScan: 7.15± 1.32 %, P<0.05). SRRS group was also found a significantly increased AI by using TUNEL method and flow cytometry analysis compared with the controls (TUNEL: 13.18±3.05 %,P<0.05; FACScan: 11.58±5.71% (P<0.05). Under electron microscope, cell shrinkage, nuclear chromatin condensation,formation of membrane blebs and apoptotic bodies were frequently observed in Sijunzi decoction group and SRRS group. The average labeling index (LI) for Ki-67 in SRRS group was significantly decreased to 8.43±2.22 % compared with the control group (10.37±t.91%) (P<0.05). The average labeling index for Ki-67 in sijunzi decoction group was 7.95±2.54 % which was lower than that of the control group, but showed no significance (P=0.07). The expression level of p53 mRNA was lower in both Sijunzi decoction group and SRRS group than that in control group (P<0.05; P<0.01). The expression of bd-2 mRNA was also decreased in SRRS group compared with the control (P<0.01).CONCLUSION: The inhibition of gastric cancer cell growth in vivo by Chinese Jianpi herbs and SRRS is related to induction of the cell apoptosis which may be involved in aberrant expression of p53 and bcl-2Ai-Guang Zhao Hai-Lei Zhao Jin-Kun Yang Lai-Di Tang Department of Oncology,Longhua Hospital,Shanghai University of Traditional Chinese Medicine,Shanghai 200032,China Xiao-Jie Jin Renji Hospital,Shanghai Second Medical University,Shanghai 200032,China 2002World Journal of Gastroenterology2002,8,5:43
3Cloning and characterization of squalene synthase and cycloartenol synthase from Siraitia grosvenorii显示文摘Mogrosides and steroid saponins are tetracyclic triterpenoids found in Siraitia grosvenorii.Squalene synthase(SQS) and cycloartenol synthase(CAS) are key enzymes in triterpenoid and steroid biosynthesis.In this study,full-length cDNAs of SgSQS and SgCAS were cloned by a rapid amplification of cDNA-ends with polymerase chain reaction(RACE-PCR) approach.The SgSQS cDNA has a 1254 bp open reading frame(ORF) encoding 417 amino acids,and the SgCAS cDNA contains a 2298 bp ORF encoding 765 amino acids.Bioinformatic analysis showed that the deduced SgSQS protein has two transmembrane regions in the C-terminal.Both SgSQS and SgCAS have significantly higher levels in fruits than in other tissues,suggesting that steroids and mogrosides are competitors for the same precursors in fruits.Combined in silico prediction and subcellular localization,experiments in tobacco indicated that SgSQS was probably in the cytoplasm or on the cytoskeleton,and SgCAS was likely located in the nucleus or cytosol.These results will provide a foundation for further study of SgSQS and SgCAS gene functions in S.grosvenorii,and may facilitate improvements in mogroside content in fruit by regulating gene expression.Huan Zhao Qi Tang Changming Mo Longhua Bai Dongping Tu Xiaojun Ma 2017Acta Pharmaceutica Sinica B2017,7,2:10
4Surface ozone observations during voyages to the Arctic and Antarctic regions显示文摘Surface ozone concentration and UV-B data between 75° N and 70° S were obtained aboard the Chinese polar scientific vessel 'Xue-long' (Snow-Dragon) during the first voyage to the Arctic and the 16th to the Antarctic in 1999-2000. Analysis of these data presents that variations of the surface ozone concentration have small amplitude during voyages except the mid-latitude in the Northern Hemisphere. As a whole, average surface ozone concentration in the Northern Hemisphere is higher than that in the Southern, and high value occurred when the ship sailed close to the continents. The average diurnal variations of the surface ozone in the Northern Hemisphere are also higher compared to the southern counterparts, and high diurnal variations were found at low latitudes, and relative low level in the polar region.Longhua Lu Lingen Bian Yanjie Cheng Changgui Lu Jie Tang 2001Chinese Science Bulletin2001,46,23:8
5Adsorption and desorption characteristics of diphenylarsenicals in two contrasting soils显示文摘Diphenylarsinic acid(DPAA) is formed during the leakage of aromatic arsenic chemical weapons in soils,is persistent in nature,and results in arsenic contamination in the field.The adsorption and desorption characteristics of DPAA were investigated in two typical Chinese soils,an Acrisol(a variable-charge soil) and a Phaeozem(a constant-charge soil).Their thermodynamics and some of the factors influencing them(i.e.,initial pH value,ionic strength and phosphate) were also evaluated using the batch method in order to understand the environmental fate of DPAA in soils.The results indicate that Acrisol had a stronger adsorption capacity for DPAA than Phaeozem.Soil DPAA adsorption was a spontaneous and endothermic process and the amount of DPAA adsorbed was affected significantly by variation in soil pH and phosphate.In contrast,soil organic matter and ionic strength had no significant effect on adsorption.This suggests that DPAA adsorption may be due to specific adsorption on soil mineral surfaces.Therefore,monitoring the fate of DPAA in soils is recommended in areas contaminated by leakage from chemical weapons.Anan Wang Shixin Li Ying Teng Wuxin Liu Longhua Wu Haibo Zhang Yujuan Huang Yongming Luo Peter Christie 2013Journal of Environmental Sciences2013,25,6:8
6Nitrogen-doped graphene nanosheets as high efficient catalysts for oxygen reduction reaction显示文摘It is of great significance in exploring alternative catalysts to platinum (Pt)-based materials for oxygen reduction reaction (ORR),because this reaction is invariably involved in various fuel cells and metal-air batteries.We herein reported the nitrogen doped graphene nanosheets (NGNSs) with pore volume of as high as 3.42 m 3 /g and investigated their potential application as ORR catalysts,it was demonstrated the NGNSs featured high activity,improved kinetics and excellent long-term stability for ORR.The NGNSs were successfully used as cathode catalysts of microbial fuel cells (MFCs) and performed even better than the commercial Pt/C (Pt 10%) catalysts at the maximum power output.CI SuQin WU YongMin ZOU JianPing TANG LongHua LUO ShengLian LI JingHong WEN ZhenHai 2012Chinese Science Bulletin2012,57,23:7
7Reply to the comment of Cheng et al.显示文摘We thank Cheng et al. for their interest in our paper 'On linking climate to Chinese dynastic change: Spatial and temporal variations of of monsoonal rain' [1]. Our paper was written largely as a response to the suggestion madeZHANG DeEr LI Hong-Chun KU Teh-Lung LU LongHua 2010Chinese Science Bulletin2010,55,32:6
8Concentrations of Heavy Metals in Suburban Horticultural Soils and Their Uptake by Artemisia selengensis显示文摘A total of 222 surface soil samples and 40 plant samples were collected to investigate the spatial distribution and possible sources of soil heavy metals and to know the uptake and translocation of heavy metals from roots to different plant parts in a representative vegetable production area in the Baguazhou Island, a suburb of Nanjing City, East China. The arithmetic mean values of total Cd, Cr,Cu, Ni, Pb, and Zn concentrations in the soils were 0.314, 133, 41.0, 58.0, 31.8, and 114 mg kg-1, respectively. All of these values were above the topsoil background values in the Nanjing area. Multivariate and geostatistical analyses showed that soil Cd contamination was derived mainly from agricultural practices. In contrast, Cu and Zn were derived mainly from soil parent materials and Pb from atmospheric deposition from highway gasoline stations. Artemisia selengensis, a locally important specialty vegetable, accumulated heavy metals primarily in the edible leaves. The general distribution of heavy metal concentrations in this plant species showed that the highest occurred in the leaves, intermediate in the stems and lowest in the roots. Cd had the highest concentration factor(root-to-soil ratio) and may pose increased health risks in the future to the local population through the consumption of contaminated vegetables.CUI Xu SUN Xulei HU Pengjie YUAN Cheng LUO Yongming WU Longhua Peter CHRISTIE 2015Pedosphere2015,25,6:6
9The vertical structure and seasonal changes of atmosphere ozone and temperature at Zhongshan Station over East Antarctica显示文摘The vertical structure of the atmospheric ozone and temperature as well as the seasonal variations is presented by using ozone sounding data at Zhongshan Station over East Antarctica from February, 2008 to February, 2009. The results show that the heights of thermal tropopause and ozone tropopause are mostly the same with yearly mean 7.9 and 7.4 km separately above the station. There is obvious seasonal variation in the pressure and temperature of the tropopause, manifested by the clear one-wave pattern with an opposite phase. As the turning point of the tropopause temperature is visible in autumn and faint in spring and winter, the tropopause height can be better confirmed by utilization of the changes of ozone. Seasonal variation of the tropospheric ozone of vertical distribution is not clear, relative to stratosphere. In the spring, ozone in the low level of stratosphere lost seriously. The minimum partial ozone in 14 km was 1.57 MPa only and the maximum partial ozone occurred in the up level stratosphere. In the rest of the season the ozone increases with height rising in the low level of stratosphere. The evidence shows that ozone lost in spring is closely related with low temperature of polar night and the process of PSC photochemical destruction ozone in the stratosphere. From the vertical characteristics and seasonal variation of ozone and temperature, it is meaningful to understand formation and development of Antarctic ozone deletion.BIAN LinGen LIN Zhong ZHANG DongQi ZHENG XiangDong LU LongHua 2012Science China Earth Sciences2012,55,2:6
10An experimental research of Weining granule in treating gastric precancerous lesions显示文摘目的将在胃的癌症前期的损害的治疗调查 Weining 小粒的潜在的治疗学的效果和机制。六十只老鼠随机被分到一个空白的组或一个模型组或到的方法收到酸或高的 retinoic -- ,中等 -- 或低 -- Weining 的剂量小粒。动物的一般条件在治疗前后被遵守。在胃的 mucosal pathohistology, telomerase 活动,增长索引(PI ) 和 apoptosis 索引(AI ) 的变化被测量。结果将军调节,包括活动并且吃,与肠的组织变形(IM ) ,不正常的增生(ATP ) 或是比在模型的那些显著地低的积极 telomerase 活动组织的老鼠有的数字在所有 Weining-granule-treated 组被改进(P < 0.05 或 P < 0.01 ) 。与模型组相比, Weining 小粒的所有剂量显著地减少了 PI (P < 0.01 ) 并且增加的 AI (P < 0.05 ) 。结论 Weining 小粒可以由禁止 telomerase 活动和胃的癌症房间并且由加速他们的 apoptosis 的增长为胃的癌症前期的损害的治疗提供一个治疗学的好处。Xing Deng Jian Liang Donghua Liu Chaoyang Zhu Longhua Li Likui Qin 2009The Chinese-German Journal of Clinical Oncology2009,8,3:6
11Flotation and adsorption of quaternary ammonium salts collectors on kaolinite of different particle size显示文摘The flotation behaviors of decyltrimethylammonium (103C), dodecyltrimethylammonium chloride (DTAC), tetradecyltrimethylammonium chloride (TTAC) and cetyltrimethylammonium chloride (CTAC) on kaolinite of different particle size fraction were studied. The adsorbed amount and adsorption isotherms of collectors on kaolinite were determined for painstaking investigation into the adsorption of quaternary amines at kaolinite-water interface by ultraviolet spectrophotometer methods. The flotation results show that the flotation recovery of kaolinite of different particle fraction increases with an increase in pH when 103C, DTAC, TTAC and CTAC are used as collectors. As the concentration of collectors increases, the flotation recovery increases. Particle size of kaolinite has a strong effect on flotation. The flotation recovery of fine kaolinite decreases with the carbon chain of quaternary ammonium salts collectors increasing, while coarse kaolinite is on the contrary. The adsorbed amount tests and adsorption isotherms show that adsorbed amount increases when the particle size of kaolinite increases or when the carbon chain length of quaternary ammonium salts increases. Within the range of flotation collector concentration, the longer the hydrocarbon chain, the more probable to be absolutely adsorbed by fine kaolinite particles and then the lower the collector concentration in the bulk, which leds to lower flotation recovery.Jiang Hao Liu Guorong Hu Yuehua Xu Longhua Yu Yawen Xie Zhen Chen Haochuan 2013International Journal of Mining Science and Technology2013,23,2:5
12Tribological and tribochemical properties of magnetite nanoflakes as additives in oil lubricants显示文摘This detailed the tribological and tribochemical properties of magnetite(Fe_3O_4) nanoflakes used as additives in #40 base oil in a four-ball tribo-tester.The average friction coefficient of the friction pair for lubricant containing the Fe_3O_4 nanoflakes of 1.5 wt%as a lubricant additive in the base oil is decreased by18.06%compared to that of solely base oil.The chemical composition of base oil with the Fe_3O_4 nanoflake additives did not change during the 48-h friction assessment.The decreased saturation magnetization and increased coercivity of magnetite nanoflakes occurred due to the distortion of the basal planes and the presence of hematite(α-Fe_3O_4) generated by the tribochemical reactions during the friction process.The multi-layer low-shear-stress tribochemical lubrication films on the surface of the friction pair could form because the nanoflake particles arrange and adhere onto the surface of the friction pair in an orderly manner,and the tribochemical reactions of the friction pair in the presence of the nanoflakes occur as Fe→FeO→Fe_3O_4→γ-FeOOH →γ-Fe_2O_3→α-Fe_2O_3.The formation of the films can improve the tribological properties.Longhua Xiang Chuanping Gao Yanmin Wang Zhidong Pan Dawei Hu 2014Particuology2014,12,6:4
13Selective feeding of bay scallop Argopecten irradians on phytoplankton community revealed by HPLC analysis of phytopigments in Bohai Sea, China显示文摘Understanding the feeding selectivity on phytoplankton by shellfi sh is currently a big challenge. In order to investigate the feeding behavior of bay scallop ( Argopecten irradians ) on phytoplankton, we compared its compositions of phytopigments in digestive glands with those in the surrounding seawater, and conducted fi ve consecutive investigations between July and November 2016 in a bay scallop culture area along coast of Qinghuangdao City, northwest of the Bohai Sea, China. Phytopigments in four-size fractionated phytoplankton of seawater (micro-(20-200 μm);nano(L)-[10-20 μm];nano(S)-[2.7-10 μm], and pico-[<2.7 μm]) and digestive glands of A . irradians were examined to investigate the selective feeding of A . irradians . Results show that fucoxanthin and peridinin constituted the major part of taxonomically diagnostic carotenoids (TDCs) in the micro- and nano(L)-phytoplankton in seawater. Compared with total phytoplankton biomass of seawater (TPB, sum of the four sizes), a substantial decrease of fucoxanthin proportion to total DCs in digestive glands was observed while that of peridinin, 19′-butanoyloxyfucoxanthin, alloxanthin and 19′-hexanoyloxy-fucoxanthin showed an obvious increase when those pigments were mainly confi ned to micro-sized phytoplankton (20-200 μm). However, zeaxanthin and prasinoxanthin were mainly confi ned to nano(s)- and pico-phytoplankton, of which the proportions in digestive glands were usually lower in TPB. The contribution of lutein to total DCs in digestive glands (with an average of 7.23%) increased compared with TPB of seawater (with an average of 0.63%) during all fi ve sampling times.JIANG Tao WANG Longhua ZHANG Fuchong FANG Xiao LU Lin ZHANG Jihong WANG Wei QU Keming CHAI Chao 2019Journal of Oceanology and Limnology2019,37,5:4
14Large area perovskite solar cell module显示文摘The recent dramatic rise in power conversion efficiencies(PCE)of perovskite solar cells has triggered intense research worldwide.However,their practical development is hampered by poor stability and low PCE values with large areas devices.Here,we developed a gas-pumping method to avoid pinholes and eliminate local structural defects over large areas of perovskite film,even for 5 x 5 cm2 modules,the PCE reached 10.6%and no significant degradation was found after 140 days of outdoor testing.Our approach enables the realization of high performance large-area PSCs for practical application.Longhua Cai Lusheng Liang Jifeng Wu Bin Ding Lili Gao Bin Fan 2017Journal of Semiconductors2017,38,1:4
15An in situ ATR-FTIR study of mixed collectors BHA/DDA adsorption in ilmenite-titanaugite flotation system显示文摘This paper researched the enhanced flotation separation performance of ilmenite and titanaugite using the mixed collector benzhydroxamic acid/dodecylamine(BHA/DDA).The interface assembly mechanism was mainly investigated through in situ attenuated total reflectance Fourier transform infrared(ATRFTIR)spectroscopy combined with the two-dimensional correlation spectroscopy(2D-COS)and X-ray photoelectron spectroscopy(XPS).It has been found that BHA/DDA mixed collectors successfully separate ilmenite from titanaugite at a molar ratio of 8:1.Zeta potential experiments suggested that,in the presence of mixed collector system,the BHA-DDA complex adsorbed on the ilmenite surface via the chemically adsorbed BHA and the electrostatically adsorbed DDA,however,the complex adsorbed on the surface of titanaugite unstably.According to in situ ATR-FTIR combined with 2D-COS and XPS results,the interface assembly mechanism of BHA/DDA is summarized as:the function group of BHA molecules first binds to the metal sites on minerals to form bidentate ligand,then DDA co-adsorbed with BHA on the surface of minerals through hydrogen bonding.DDA may change the adsorption modes of some BHA on the ilmenite surface from four-membered ring to five-membered ring,while the modes on the titanaugite surface is true opposite.Finally,recommended adsorption configurations of the BHA/DDA complex on the two mineral surfaces are proposed.Liping Luo Houqin Wu Longhua Xu Jinping Meng Jiahui Lu Huan Zhou Xiaomei Huo Lingyun Huang 2021International Journal of Mining Science and Technology2021,31,4:4
16Structural mechanism of cooperative activation of the human calcium-sensing receptor by Ca^(2+) ions and L-tryptophan显示文摘The human calcium-sensing receptor(CaSR)is a class C G protein-coupled receptor(GPCR)responsible for maintaining Ca^(2+)homeostasis in the blood.The general consensus is that extracellular Ca^(2+)is the principal agonist of CaSR.Aliphatic and aromatic L-amino acids,such as L-Phe and L-Trp,increase the sensitivity of CaSR towards Ca^(2+)and are considered allosteric activators.Crystal structures of the extracellular domain(ECD)of CaSR dimer have demonstrated Ca^(2+)and L-Trp binding sites and conformational changes of the ECD upon Ca^(2+)/L-Trp binding.However,it remains to be understood at the structural level how Ca^(2+)/L-Trp binding to the ECD leads to conformational changes in transmembrane domains(TMDs)and consequent CaSR activation.Here,we determined the structures of full-length human CaSR in the inactive state,Ca^(2+)-or L-Trp-bound states,and Ca^(2+)/L-Trp-bound active state using single-particle cryo-electron microscopy.Structural studies demonstrate that L-Trp binding induces the closure of the Venus flytrap(VFT)domain of CaSR,bringing the receptor into an intermediate active state.Ca^(2+)binding relays the conformational changes from the VFT domains to the TMDs,consequently inducing close contact between the two TMDs of dimeric CaSR,activating the receptor.Importantly,our structural and functional studies reveal that Ca^(2+)ions and L-Trp activate CaSR cooperatively.Amino acids are not able to activate CaSR alone,but can promote the receptor activation in the presence of Ca^(2+).Our data provide complementary insights into the activation of class C GPCRs and may aid in the development of novel drugs targeting CaSR.Shenglong Ling Pan Shi Sanling Liu Xianyu Meng Yingxin Zhou Wenjing Sun Shenghai Chang Xing Zhang Longhua Zhang Chaowei Shi Demeng Sun Lei Liu Changlin Tian 2021Cell Research2021,31,4:3
17Refinement of Methodology for Cadmium Determination in Soil Micro-Arthropod Tissues显示文摘Highly precise and reliable determination of heavy metals in soil micro-arthropod tissues remains a challenge because of the small size of the animals and their typical low abundance in metal-contaminated agricultural soils. The present study sought to develop a method for cadmium(Cd) determination in soil micro-arthropods by optimizing the sample digestion procedure, reducing sample weight, modifying sample pre-treatment and validating the methodology with field samples. The optimized digestion conditions comprised a sample mass of 50–150 μg, digestion reagent of nitric acid:hydrogen peroxide(3:1), digestion temperature of 105℃,digestion period of 3 h and digestion volume of 30 μL. Defecation of the standard Collembola Folsomia candida(92 h) and the indigenous Collembola Onychiurus yodai(42 h) and ultrasonic cleaning of F. candida increased the accuracy of Cd determination.The recovery of Cd using the refined procedure was 98.9% and the limits of detection and quantification were 0.002 and 0.008 μg L^(-1), respectively. The within-batch precision values were < 3%. The Cd concentrations in the tissues of the Collembola Isotoma sp.collected from a range of metal-contaminated fields determined by the improved method were consistent with the Cd concentrations in the field soils. The results indicate that the optimized method can be used for more accurate or reliable determination of Cd concentrations in soil micro-arthropod tissues.ZHU Dong KE Xin WU Longhua HUANG Yujuan Peter CHRISTIE LUO Yongming 2017Pedosphere2017,27,3:3
18Period selection for integrated controller tasks in cyber-physical systems显示文摘Performance optimization of cyber-physical systems(CPS)calls for co-design strategies that handle the issues in both computing domain and physical domain.Periods of controller tasks integrated into a uniprocessor system are related to both control performance and real-time schedulability analysis simultaneously.System performance improvement can be achieved by optimizing the periods of controller tasks.This paper extends an existing model to select task periods in real-time for CPS with fixed priority controller tasks scheduled by rate-monotonic algorithm.When all the tasks can be integrated,the analytic solution of the problem is derived by using the method of Lagrange multipliers and gradient descent method is evaluated to be suitable online.To further deal with the condition that the system is overloaded,an integrated method is proposed to select periods of tasks online by selecting a subset of tasks first and then optimizing the periods for them.Experimental results demonstrate that our method yields near-optimal result with a short running time.Du Chenglie Tan Longhua Dong Yali 2015Chinese Journal of Aeronautics2015,28,3:3
19Control principles of micro-source inverters used in microgrid显示文摘Since micro-sources are mostly interfaced to microgrid by power inverters,this paper gives an insight of the control methods of the micro-source inverters by reviewing some recent documents.Firstly,the basic principles of different inverter control methods are illustrated by analyzing the electrical circuits and control loops.Then,the main problems and some typical improved schemes of theωU-droop grid-supporting inverter are presented.In results and discussion part,the comparison of different kinds of inverters is presented and some notable research points is discussed.It is concluded that the most promising control method should be theωU-droop control,and it is meaningful to study the performance improvement methods under realistic operation conditions in the future work.Wenming Guo Longhua Mu 2016Protection and Control of Modern Power Systems2016,1,1:3
20Microscale insights into the influence of grinding media on spodumene micro-flotation using mixed anionic/cationic collectors显示文摘Here,the influence of grinding media with different shapes on the flotation performance of spodumene and its potential mechanism from microscale insights was investigated using a single mineral flotation experiment,X-ray diffraction(XRD)test,scanning electron microscopy combined with energy dispersive spectrometry(SEM-EDS),atomic force microscope(AFM)and X-ray photoelectron spectroscopy(XPS).The flotation data indicated that under anionic/cationic(sodium oleate(NaOL)/DDA)collectors system,the rod milled spodumene has a higher floatability than ball milled ones.XRD results confirmed that rod medium makes spodumene exposed more{110}and{100}planes,while ball medium makes spodumene exposed more{010}planes.The typical anisotropic surface of spodumene makes the surface of rod milled spodumene possess more Al sites,further confirmed by SEM-EDS and XPS results.Additionally,it was found that the rod milled spodumene presents a larger value of elongation and flatness,which are parameters closely related to bubble adhesion.AFM analysis indicated that rod milled products have a rougher surface,while ball milled products have a smoother surface.Consequently,the rod medium enhanced the adsorption of NaOL/DDA on the spodumene surfaces.This work provides theoretical guidance for optimizing the separation of spodumene from the perspective of grinding.Liping Luo Longhua Xu Xinzhang Shi Jinping Meng Ruohua Liu 2022International Journal of Mining Science and Technology2022,32,1:3
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