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Changes of spring wind erosion based on wind erosion climate factor in the black soil region of Northeast China
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作者 YAN Ping JI Sheng-tai +5 位作者 LI Xiu-fen ZHU Hai-xia WANG Liang-liang ZHAI Mo WANG Ping ZHAO Hui-ying 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1712-1724,共13页
The dry and windy climate and low ground cover in spring in the black soil region of Northeast China make the soil strongly affected by wind erosion,which seriously threatens the food security and ecological security ... The dry and windy climate and low ground cover in spring in the black soil region of Northeast China make the soil strongly affected by wind erosion,which seriously threatens the food security and ecological security of this region.In this paper,based on the daily observation data of 124 meteorological stations in study area from 1961 to 2020,seasonal and monthly wind erosion climate factor(C)in spring(March to May)were calculated by using the method proposed by the Food and Agriculture Organization of the United Nations(FAO),the wind erosion characterization in spring were systematically analyzed based on C by various statistical analysis methods.The results showed that in the past 60 years,spring wind erosion climate factor(CSp)and monthly C of the whole region and each province(region)all showed highly significant decreasing trend,but they began to show rebounded trend in the middle or late 2000s.CSp of the study area showed a significant upward trend since 2008 with an increase of 4.59(10a)^(-1).The main contributors to this upward trend are the changes of C in March and in April.For the four provinces(regions),CSp in Heilongjiang,Jilin,Liaoning and eastern Inner Mongolia all showed rebounded since 2008,2011,2008 and 2009,respectively.The rebounded trend of CSp in eastern Inner Mongolia was the most obvious with a tendency rate of 11.27(10a)^(-1),and its mutation occurred after 1984.The rebound trend of CSp in Heilongjiang Province takes the second place,with a trend rate of 4.72(10a)^(-1),but there’s no obvious time mutation characteristics.The spatial characteristics of CSpand monthly C are similar,showing decreasing characteristics centered on the typical black soil belt of Northeast China.Compared with 1961-1990,in the period from 1991 to 2020,the proportion of high value areas(CSp>35,monthly C>10)has decreased to varying degrees,while the proportion of low value areas(CSp≤10,monthly C≤4)has increased.The trends of seasonal and monthly C in 82.2%~87.7%of the stations show significant decreases at 95%confidence level.CSp is closely related to wind speed at 2m height,temperature difference,minimum temperature and precipitation in the same period,of which the correlation between CSp and wind speed is the strongest,indicating that the main control factor for CSp in the study area is wind speed,but the impact of the change of temperature and precipitation on CSp cannot be ignored. 展开更多
关键词 Wind erosion climate erosivity Spatiotemporal 1characteristics Climate change Rebounded trend Typical black soil region Northeast China
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Effects of different dietary energy and protein levels and sex on growth performance,carcass characteristics and meat quality of F1 Angus x Chinese Xiangxi yellow cattle 被引量:22
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作者 Lingyan Li Yuankui Zhu +2 位作者 Xianyou Wang Yang He Binghai Cao 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第4期485-496,共12页
Background:The experiment evaluated the effect of nutrition levels and sex on the growth performance,carcass characteristics and meat quality of F1 Angus × Chinese Xiangxi yellow cattle.Methods:During the backg... Background:The experiment evaluated the effect of nutrition levels and sex on the growth performance,carcass characteristics and meat quality of F1 Angus × Chinese Xiangxi yellow cattle.Methods:During the background period of 184 d,23 steers and 24 heifers were fed the same ration,then put into a2×2×2 factorial arrangement under two levels of- dietary energy(TON:70/80%DM),protein(CP:11.9/14.3%DM)and sex(S:male/female) during the finishing phase of 146 d.The treatments were-(1) high energy/low protein(HELP),(2) high energy/high protein(HEHP),(3) low energy/low protein(LELP) and(4) low energy/high protein(LEHP).Each treatment used 6 steers and 6 heifers,except for HELP- 5 steers and 6 heifers.Results:Growth rate and final carcass weight were unaffected by dietary energy and protein levels or by sex.Compared with the LE diet group,the HE group had significantly lower dry matter intake(DMI,6.76 vs.7.48 kg DM/d),greater chest girth increments(46.1 vs.36.8 cm),higher carcass fat(19.9 vs.16.3%) and intramuscular fat content(29.9 vs.22.8%DM).The HE group also had improved yields of top and medium top grade commercial meat cuts(39.9 vs.36.5%).The dressing percentage was higher for the HP group than the LP group(53.4 vs.54.9%).Steers had a greater length increment(9.0 vs.8.3 cm),but lower carcass fat content(16.8 vs.19.4%) than heifers.The meat quality traits(shear force value,drip loss,cooking loss and water holding capacity) were not affected by treatments or sex,averaging 3.14 kg,2.5,31.5 and 52.9%,respectively.The nutritive profiles(both fatty and amino acid composition) were not influenced by the energy or protein levels or by sex.Conclusions:The dietary energy and protein levels and sex significantly influenced the carcass characteristics and chemical composition of meat but not thegrowth performance,meat quality traits and nutritive profiles. 展开更多
关键词 Carcass characteristics Energy F1 Angus × Chinese Xiangxi yellow cattle Growth performance Meat quality Protein Sex
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Mineralogical characteristics of polymetallic sulfides from the Deyin-1 hydrothermal field near 15°S, southern Mid-Atlantic Ridge 被引量:4
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作者 WANG Shujie LI Huaiming +3 位作者 ZHAI Shikui YU Zenghui SHAO Zongze CAI Zongwei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第2期22-34,共13页
A seafloor hydrothermal field, named Deyin-1 later, near 15°S southern Mid-Atlantic Ridge(SMAR) was newly found during the 22 nd cruise carried out by the China Ocean Mineral Resources Research & Development A... A seafloor hydrothermal field, named Deyin-1 later, near 15°S southern Mid-Atlantic Ridge(SMAR) was newly found during the 22 nd cruise carried out by the China Ocean Mineral Resources Research & Development Association(COMRA). Sulfide samples were collected at three stations from the hydrothermal field during the26 th cruise in 2012. In this paper, mineralogical characteristics of the sulfides were analyzed with optical microscope, X-ray diffractometer, scanning electron microscope and electron microprobe to study the crystallization sequence of minerals and the process of hydrothermal mineralization. According to the difference of the ore-forming metal elements, the sulfide samples can be divided into three types:(1) the Ferich sulfide, which contains mainly pyrite and chalcopyrite;(2) the Fe-Cu-rich sulfide consisting predominantly of pyrite, chalcopyrite and isocubanite, with lesser amount of sphalerite, marmatite and pyrrhotine; and(3) the Fe-Zn-rich sulfide dominated by pyrite, sphalerite and marmatite, with variable amounts of chalcopyrite, isocubanite, pyrrhotine, marcasite, galena and gratonite. Mineral precipitations in these sulfides are in the sequence of chalcopyrite(isocubanite and possible coarse pyrite), fine pyrite,sphalerite(marmatite), galena, gratonite and then the minerals out of the dissolution. Two morphologically distinct generations(Py-I and Py-II) of pyrite are identified in each of the samples; inclusions of marmatite tend to exist in the coarse pyrite crystals(Py-I). Sphalerite in the Fe-Zn-rich sulfide is characterized by a"chalcopyrite disease" phenomenon. Mineral paragenetic relationships and a wide range of chemical compositions suggest that the environment of hydrothermal mineralization was largely changing. By comparison, the Fe-rich sulfide was formed in a relatively stable environment with a high temperature, but the conditions for the formation of the Fe-Cu-rich sulfide were variable. The Fe-Zn-rich sulfide was precipitated during the hydrothermal venting at relatively low temperature. 展开更多
关键词 mineralogical characteristics mineral-forming sequence polymetallic sulfides Deyin-1 hydrothermal field southern Mid-Atlantic Ridge
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THE SYNTHESIS AND CHARACTERISTICS OF THE COORDINATION COMPOUNDS OF 2-MERCAPTOPYRIDINE-1-OXIDE WITH THE FIPST TRANSITION SERIES METALS
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作者 Bao Lin SONG Zai Sheng LU De Zhong NIU Yang CAO Department of Chemistry,Xuzhou Teacher’s College, Xuzhou 221009Cheng ZENG Coordination Chemistry Institute,Nanjing University,Nanjing 210008 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期117-118,共2页
The stability of the coordination compounds of the first transition series metal ions(Mn(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Cu(Ⅱ)and Zn(Ⅱ))with 2-mercaptopyridine-1- oxide is reported.A coordination compound CoL_2 is synthesized and... The stability of the coordination compounds of the first transition series metal ions(Mn(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Cu(Ⅱ)and Zn(Ⅱ))with 2-mercaptopyridine-1- oxide is reported.A coordination compound CoL_2 is synthesized and characterized for the first time. 展开更多
关键词 In ab CO THE SYNTHESIS AND CHARACTERISTICS OF THE COORDINATION COMPOUNDS OF 2-MERCAPTOPYRIDINE-1-OXIDE WITH THE FIPST TRANSITION SERIES METALS
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Expression of DLK1 protein and its correlation with renal cell carcinoma pathological characteristics
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作者 邹霜梅 《外科研究与新技术》 2011年第4期235-235,共1页
Objective To identify the expression of DLK1 protein in different types of renal cell carcinomas and its correlations with pathological characteristics and metastasis. Methods Immunohistochemistry analysis was perform... Objective To identify the expression of DLK1 protein in different types of renal cell carcinomas and its correlations with pathological characteristics and metastasis. Methods Immunohistochemistry analysis was performed to evaluate the expression of DLK1 protein in 展开更多
关键词 DLK CELL Expression of DLK1 protein and its correlation with renal cell carcinoma pathological characteristics
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Multi-scale Kalman filters algorithm for GPS common-view observation data based on correlation structure of discrete wavelet coefficients
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作者 OU Xiaojuan ZHOU Wei 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2007年第3期317-321,共5页
Global positioning system(GPS)common-view observation data were processed by using the multi-scale Kalman algorithm based on a correlative structure of the discrete wavelet coefficients.Suppose that the GPS commonview... Global positioning system(GPS)common-view observation data were processed by using the multi-scale Kalman algorithm based on a correlative structure of the discrete wavelet coefficients.Suppose that the GPS commonview observation data has the 1/f fractal characteristic,the algorithm of wavelet transform was used to estimate the Hurst parameter H of GPS clock difference data.When 0<H<1,the 1/f fractal characteristic of the GPS clock difference data is a Gaussian zero-mean and non-stationary stochastic process.Thus,the discrete wavelet coefficients can be discussed in the process of estimating multi-scale Kalman coefficients.Furthermore,the discrete clock difference can be estimated.The single-channel and multi-channel common-view observation data were processed respectively.Comparisons were made between the results obtained and the Circular T data.Simulation results show that the algorithm discussed in this paper is both feasible and effective. 展开更多
关键词 COMMUNICATION multi-scale Kalman filters 1/f fractal characteristic correlation structure fractal increment
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EVI1 expression,clinical and cytogenetical characteristics in 447 patients with acute myeloid leukemia
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作者 何雪峰 《China Medical Abstracts(Internal Medicine)》 2017年第1期55-56,共2页
Objective To investigate EVI1 expression and its associated clinical and cytogenetic characteristics in 447acute myeloid leukemia(AML)patients.Methods EVI1expressions were measured in 447 AML cases from Jan.2007 to Ap... Objective To investigate EVI1 expression and its associated clinical and cytogenetic characteristics in 447acute myeloid leukemia(AML)patients.Methods EVI1expressions were measured in 447 AML cases from Jan.2007 to Apr.2015 to couple with clinical。 展开更多
关键词 EVI1 expression clinical and cytogenetical characteristics in 447 patients with acute myeloid leukemia HIGH AML
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