最新刊期
卷 49 ， 期 3 ， 2010
- 摘要：Let G be a finite abelian group, and let S be a squarefree, zerosumfree sequence of elements in G. Let f(S) denote the number of elements in G which can be expressed as the sum over a nonempty subsequence of S. When the length of Sequals to 5, the result f(S)≥13 is obtained. All cases of S whenf(S)=13 are described.关键词：zerosumfree;square free;sequence
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发布时间：2023-12-11 - 摘要：The group invariant solutions of the KdV type equation with discrete delay ut(t,x)+u(t,x)ux(t,x)+uxxx(t,x)=g(x,u,u(t-τ,x)) are studied. According to the definition of an equivalence Lie group for delay differential equations, we construct the determining equations and admitted Lie groups of delay KdV type equation. Then the group invariant solutions of the delay KdV type equation are obtained.关键词：KdV type equation with discrete delay;admitted Lie group;group invariant solution
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发布时间：2023-12-11 - 摘要：A stagestructured delayed pest management predatorprey model with impulsive transmitting on predators (beneficial insect) and chemical control on prey (pests) concern was considered. According to the living resources managements reality, improved the predatorprey model, sufficient condition of the global attractivity of pestexterminate periodic solution and permanence of the system were obtained. The results provide reliable tactical basis for the practical pest management.关键词：stagestructured;impulsive;delayed;pestextinction;global attractivity;permanence
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发布时间：2023-12-11 - 摘要：The existence and stability of semitrivial periodic solutions and the existence of positive periodic solutions for the competition model in an unstirred chemostat are discussed. By using comparison theorems for parabolic equation, stability theory, the maximum principle and the theory of LeraySchauder degree, the existence and stability of semitrivial periodic solutions to the system are proved. The sufficient conditions of existence of positive periodic solutions to the system are obtained.关键词：Chemostat;stability;theory of degree;periodic solution
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发布时间：2023-12-11 - 摘要：By means of the generalized Mawhins continuation theorem and some inequality skills, with constructing the appropriate operators, the existence of periodic solution for a fourthorder pLapalcian differential equation is discussed. Using a improved priori estimate, combining the classify of p, two sufficient conditions are presented to guarantee the existence of at least one periodic solution for this kind of differential equations.关键词：generalized Mawhins continuation theorem;periodic solution;pLapalcian differential equation
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发布时间：2023-12-11 - 摘要：To investigate the Robin inverse problem. Firstly, formulate the problem to a boundary equation, then apply TV regularization method to solve it. Lastly, present the numerical examples to demonstrate the efficiency of the TV regularization.关键词：Robin inverse problem;TV regularization;lagged diffusivity fixed point iterative method
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发布时间：2023-12-11 - 摘要：The perturbative method for calculating the effect of imperfectly conducting walls on the propagation of electromagnetic waves in cylindrical waveguides is reformulated. The equation for calculating the corrected eigenvalues is obtained in a quite different form. In comparison with the previous result, it is physically more transparent, formally simpler and more compact, and more convenient for practical calculations. 〖JP2〗Special cases overlooked previously are discussed. Results on the coaxial line are presented.〖JP〗关键词：waveguide;perturbative method;finite conductivity
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发布时间：2023-12-11 - 摘要：The GaAs quantum ring energies and sizedependent effect are studied by Bspline technique in strong magnetic field. The calculated results show: In the strong magnetic field （B>3T）, ground state energies E1 and absolute value of Coulomd energy EC increases with magnetic field strength 〖WTBX〗B〖WTBZ〗，and the distance between E1-B curves of different angular momentum（m=-1,-2,-3）are pulled apart by Coulomd field of positive charge placed in the center; As quantum ring radius r0 increase, every E1-r0 curve has a minimum position r00, which decreases as the magnetic field strengthB increasing, and the distance between E1-r0 curves in different magnetic field strength Bare pulled closely by Coulomd field of positive charge placed in the center; The absolute value of Coulomd energy EC decreases linearly as the magnetic field strength B increasing. The ground state energies E1increase with harmonic potential ω0, the E1-ω0 curves of different angular momentum（m=-1,-2,-3） cross each other under the impact of Coulomd field，which lead to a change of the energy levels in the order. The absolute value of Coulomd energy EC decreases nonlinearly as ω0 increasing.关键词：Bspline technique;quantum ring;ground state energies
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发布时间：2023-12-11 - 摘要：The property of a 2dimensional 2electron quantum dot (QD) subjected to an external magnetic field B and affected by a charged impurity is studied. The impurity is located at the zaxis by a distance d from the plane of the dot. The energy spectra of lowlying state of the QD are obtained by the exact diagonalization approach. The evolution of the angular momentum L0 and the spin S0 of the ground state in accord with B and d has been calculated, the results are summarized and plotted in a (L0,S0) diagram. The (L0,S0) diagram indicates that the transitions of L0 and S0 are matched in peculiar way.关键词：quantum dot;magnetic field;impurity;ground state
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发布时间：2023-12-11 - 摘要：Numuerical models of polypropylene fiber reinforced cement (PPRC) with different incorporation rate have been built to analyze PPRC material. With these models the fracture track, crack initiation, coalescence and development, interaction and final penetration have all been simulated. In the meantime, some basic issues during failure process, like spatiotemporal distribution of acoustic emission and precursor pattern of the failure have also been investigated. The results show that the toughness and the bending strength have been improved with increasing polypropylene fiber incorporation rate.关键词：PPRC;incorporation rate;microsimulation;failure process;acoustic emission
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发布时间：2023-12-11 - 摘要：For short and middle length LDPC codes, the oscillation of LLR owing to cycles degrades the performance of BP algorithm. In order to minimize the oscillation of LLR during BP decoding process, an improved BP algorithm with serial update scheduling using weighted average message to update the message of checktovariable node is proposed. Currently computed message of checktovariable node and the message of old checktovariable node are weighted and then added up to update the message of checktovariable node. By higher weighted currently computed message of checktovariable node than the message of old checktovariable node, the improved algorithm effectively minimizes oscillation of LLR, at the same time, keeps normal BP message propagation and low compute complexity. Simulation results show that, for short and middle length LDPC codes, the improved algorithm achieves more noticeable error performance than CSBP algorithm at middle to high signal to noise ratio.关键词：LDPC codes;beliefpropagation;lterative decoding;factor graph
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发布时间：2023-12-11 - 摘要：A numerical simulation of electron cyclotron current drive in HL-2A tokamak is performed with the relativistic FokkerPlanck equation incorporated into a ray tracing code. With the singlenull divertor configuration on the HL-2A tokamak,the current dirve for the ordinary electron cyclotron wave, injected from the low field side, are analyzed. Numerical results show that current drive efficiency is low and can be affected dramatically by the change of temperature in HL-2A.关键词：HL-2A;electron cyclotron wave;current dirve
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发布时间：2023-12-11 - 摘要：The density functional theory (DFT) combined with the conductorlike polarizable calculation model (CPCM) was used to investigated the first hydrolysis step under acidic condition of a Ru (III) complex ［ImH］［〖WTBX〗trans〖WTBZ〗RuCl4(DMSO)(Im)］(NAMIA) and the first ruthenium anticancer complex that has entered clinical testing. Full geometry optimizations and frequency calculations for each transition states and intermediate species were carried out at the UB3LYP/(LanL2DZ+6-31G(d)) level in gas phase. Singlepoint energies were calculated at the UB3LYP/(LanL2DZ(f)+6-311++G(3df,2pd) level based on the optimized structures in acidic solution. The geometrical and electronic structures, and detailed energy profiles during the hydrolysis processes of the complex were investigated. It was found interestingly that the hydrolysis of DMSO ligand in acidic solution has thermodynamic preference over the hydrolysis of Cl atom, which was in good agreement with the experimental results. Thus this work can offer a significant theoretical reference for deeply understanding the hydrolysis mechanism of NAMIA.关键词：NAMIA;anticancer drug;acidic condition;hydrolysis mechanism;density functional theory (DFT)
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发布时间：2023-12-11 - 摘要：The orbicular molecularly imprinted polymer (OCMIP) was prepared by two steps including the precipitation polymerization and the opening the GMA epoxide ring. Then the hydrophilic external layer on the surface of OCMIP was formed. The OCMIP was characterized by infrared spectra and scanning electron microscopy (SEM). Water absorption measurement showed the OCMIP had stronger water compatible than MIP. When the proportion of MAA/GMA was 1∶〖KG-*2〗1, and DVB is 3 times of MAA co GMA, the particle shapes of MIPs were uniform and the recognition and release of OCMIP in polar solvent were satisfactory.The results showed GMA added in the polymers could adjust the capability of release of the polymers certainly. After the GMA epoxide ring was opened, OCMIP synthesized was more suitable to be employed in biological media because of the reduction of nonspecific hydrophobic interactions. In addition, the polymers had the capability of recognition, also could satisfy the study of both drug recognition and sustainedrelease in polar solvent.关键词：snaproxen;precipitation polymerization;molecularly imprinted polymers;recognition and release
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发布时间：2023-12-11 - 摘要：Theacrine was prepared, isolated and purified from Camellia assamica var. kucha by highspeed countercurrent chromatography. A twophase solvent system composed of hexanedichloromethanemethanolwater (1∶5∶4∶2, v/v/v/v) was selected with comprehensive analysis of the settling time, the ratio of up and down phases volume and the K value. Five mg of theobromine, 389 mg of theacrine and 41 mg of caffeine with their purities over 99% were obtained from 222 g of the crude extract of Camellia assamica var. kucha under the condition of a flow rate of 20 mL/min, 800 r/min and the detection wavelength of 278 nm. The obtained fractions were analyzed by high perform liquid chromatography, compared with standard substance and identified by MS, 1H NMR and 13C NMR methods. Theacrine was the first time isolated from Camellia assamica var. kucha by HSCCC, which is a simple, rapid and effective method.关键词：HSCCC;Camellia assamica var. kucha;purine alkaloid;theacrine
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发布时间：2023-12-11 - 摘要：A regular nanocrystalline supramolecular MgAl hydrotalcite was prepared via glycolfrequency microwavehydrothermal using MgCl2·6H2O,AlCl3·6H2O,Na2CO3 as raw material as precipitator. Hydrotalcite samples were characterized by Xray diffraction (XRD)，scan electron microscope (SEM), transmission electron microscope (TEM)，IR, thermal analysis (TGDTA)，and BETN2 surface area measurements. The images of SEM and TEM showed that the hydrotalcite exhibited as a homogeneous and hexagonal sheet. The XRD result indicated that the hydrotalcite was well crystallized. The influences of tradition hydrothermal, frequency microwavehydrothermal and glycolfrequency microwavehydrothermal on the sample character were investigated. A MgAl hydrotalcite with welldefined shape, obvious intercalated structure, well regular quality and welldispersing capability was obtained when glycol volume ratio was 10% at 120 ℃ for 5 h.关键词：frequency microwave;glycol;hydrothermal;MgAl hydrotalcite
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发布时间：2023-12-11 - 摘要：Organotin(Ⅳ) compound {［(nC4H9)2Sn(05·O2CC12H10N)(05·CH3O)］2O}2 was synthesized by the reaction of n dibutyltin oxide with Nphenylanthranilic acid. The compound was characterized by elemental analysis, IR and 1H NMR analyses. The crystal structure was determined by Xray single crystal diffraction method. The result indicates that crystal belongs to triclinic, space group P-1 with a =1173(2) nm,b = 1256(2) nm, c= 1329(2) nm, α = 8229(3)°, β = 7183(3)°, γ = 6536(3)°, V = 1690(5) nm3, Z = 1, μ= 1509 mm-1, Dc = 1425 Mg·m-3, F(000) =736, R = 0056 9, wR = 0158 9, GOF = 1074. The complex is a centrosymmetric structure mode with a fourmember central endocyclic Sn2O2 unit in which two bridged oxygen atoms both connect with an exocyclic tin atom. The endocyclic tin atoms and the exocyclic tin atoms are all fivecoordination and have coordination geometry of distorted trigonal bipyramid.关键词：organotin(Ⅳ) compound;Nphenylanthranilic acid;synthesis;crystal structure
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发布时间：2023-12-11 - 摘要：The forest ecosystem services evaluation is basis that knows better forest and harmonious development that human being with forest. So far there is not unitary evaluation indices system and evaluation method, though the history of forest ecosystem services evaluation research has more than 30 years. Base on the evaluation criterion of forest ecosystem services that is promulgate by State Forestry Administration, P.R.China, and observation data of Chinses Forest Ecosystem Research Network (CFERN) stations that continuous observed with many years and inventory data, the detailed and dynamic evaluation of Chinese pine forest ecosystem services in China on quantity in kind and value were done. The results showed that the total value of Chinese pine forest ecosystem services in China in the period of “The Ninth Five Plan” was 148×1012 Yuan（RMB）a year, the average value was 79 872 Yuan·hm-2·a-1. The total value of Chinese pine forest ecosystem services in China in the period of “The Tenth Five Plan” was 140×1012 Yuan（RMB）a year, the average value was 76 689 Yuan·hm-2·a-1. In the period of “The Tenth Five Plan”, the oakery forest ecosystem services in China conserved water 707×1010 m3, protected soil 582×108 t, fixed carbon 094×108 t, produced anion 185×1021 absorbed SO2 159×109 kg, retarded dustfall 384×1011 kg. Along 27 provinces that have oakery forest, the maximum quantity in kind benefit province from oakery forest ecosystem services is Heilongjiang province, the minimum quantity in kind benefit province from oakery forest ecosystem services is Qinghai province; The maximum at total value is Yunnan province, the minimum is Shanxi province.关键词：forest ecosystem service;oakery forest;quantity in kind;value;evaluation
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发布时间：2023-12-11 - 摘要：To probe into the opportunities for breaking the barriers of wheat yield using synthetic hexaploid wheat (SHW), two sets of recombinant inbred lines (RILs), S12 (SynCD780×Chuanyu12, 131 lines) and S16 (SHWderived variety Chuanmai42×Chuannong16, 127 lines), were planted in multienvironments (year×site) in 2006-2008. Phenotypic data were collected for fifteen agronomic traits of both S12 and S16 and 280 microsatellite markers were employed to genotype lines of S16. Continuous variation and transgressive segregation for all tested traits were observed. Grain yield of superior lines in S12 was 64% higher than Chuanyu12 achieved by increasing kernel weight (≈ 10%). Average grain yield of the top ten highyielding lines in S16 was up to 79 t/hm2, 181% higher than Chuannong16 by increasing both kernel weight and grains m-2. Using singlemarker regression and interval mapping, a total of 55 putative QTLs with a LOD score ＞30 based on S16 were detected, of which 7 were for grain yield, 40 for yield components, and 8 for rates of grain and biomass production. For 38 (691%) of them, alleles from the SHWderived variety Chuanmai42 were associated with a positive effect on yieldrelated traits. The present studies indicated that breaking barriers of wheat yield using SHW is feasible.关键词：synthetic hexaploid wheats;grain yield;yieldrelated traits;QTL analysis
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发布时间：2023-12-11 - 摘要：The gene expression patterns of CYP1A1 and Aryl hydrocarbon receptor (AhR2) of red seabream (〖WTBX〗Pagrus major〖WTBZ〗) were both measured using realtime quantitative PCR (qPCR) when fish exposed to environmentally relevant concentration of BaP (01, 05 and 10 μg/L, respectively). The results showed that CYP1A1 mRNA and AhR2 mRNA could be induced significantly, besides, the time of AhR2 mRNA induced ahead of the time of CYP1A mRNA induced. The two genes were induced markedly at the begining of BaP exposure, and then decreased to the basal levels after 72 h. The results demonstrate that BaP can regulate CYP1A1 and AhR2 transcript in a dose and time dependent manner.关键词：Benzo［a］Pyrene (BaP);Pagrus major;realtime quantitative PCR;cytochromeP450 (CYP1A1);aryl hydrocarbon receptor (AhR)
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发布时间：2023-12-11 - 摘要：Electroporation is widely used for highly efficient transformation of Saccharomyces cerevisiae. As many strains degenerate over time or over environmental exposure, their electroporation efficiencies could drop markedly by 2 to 3 orders of magnitude. Here we describe a modified electroporation procedure which included single stranded carrier DNA for electroporation as well as a postelectroporation growth period in YPD medium, which gave rise to 13 fold enhancement in transformations than an optimized lithium acetate (LiAc) and dithiothreitol (DTT) Pretreatment protocol previously reported. An enhancement of 114 fold on Pichia pastoris transformations has been observed using the modified procedure. The modified method enhanced the transformation efficiencies of some degenerated S. cerevisiae strains by nearly 100 fold. It will enable molecular manipulations in all kinds of S. cerevisiaeand P. pastoris strains by allowing propagations of all sorts of DNA libraries made from minute samples.关键词：electroporation;Saccharomyces cerevisiae;single stranded carrier DNA;postelectroporation growth;Pichia pastoris
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发布时间：2023-12-11 - 摘要：The influence of drug concentration and pH on the photodegradation of ciprofloxacin was investigated, and a reversephase highperformance liquid chromatographic method was developed for detecting the changes of ciprofloxacin content in water and sediments. Photodegradation of ciprofloxacin in natural light was most rapid at a concentration of 1 mg·L-1 among the three concentrations tested (1,5 and 10 mg·L-1). After 72 h, the amounts of ciprofloxacin remaining with and without sediments were 19% and 20%, respectively. The photodegradation rate was inversely proportional to the initial drug concentration. Ciprofloxacin was most sensitive to photodegradation at pH 9 among the four pH levels tested 〖JP2〗(pH =3, 5, 9, 11), when the〖JP〗 drug was in zwitterionic form. The stability increased considerably when pH=3. After 48 h, the amounts of ciprofloxacin remaining in water were 22.6 % and 95.7%, respectively. When ciprofloxacin was released into microcosms, the concentration of ciprofloxacin in water decreased rapidly, but increased concomitantly in sediments. After 45 days ciprofloxacin was undetectable in water, but a substantial concentration remained in the sediments.(approximately 93.86 μg·kg-1).关键词：ciprofloxacin hydrochloride;photodegradation;microcosmos system
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发布时间：2023-12-11 - 摘要：Gene expression plasmid pIRES/ch3C8 of B7-2 humanmouse chimeric antibody was constructed, eukaryotic cell line CHO was transfected with pIRES/ch3C8 by liposome method, and prepared B7-2 humanmouse chimeric antibody (named ch3C8). It could recognize B7-2 molecule on Raji, which is a human malignant B lymphoma cell line, and induce apoptosis of Raji. In addition, the ADCC and CDC effect was effectively mediated with the Fc fragment of the ch3C8 which come from human Ig. It was further showed that Raji lost oncogenicity with ch3C8 treated, which inoculated BALB/c nude mouse. ch3C8 will have a potential application value on B7-2 related tumor biotherapy.关键词：B7-2;chimeric antibody;lymphoma;apoptosis;ADCC effect;CDC effect
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发布时间：2023-12-11 - 摘要：Through the pollen analysis, combined with the informations on dating and sedimentation of two drilling cores located at different depositiongeomorphological area in the northern and southern part of Guangzhou, the deposition environmental and climatic changes since the late Pleistocene in Guangzhou, the Pearl River Delta, are suggested. Pollen records show that the climate during the late Pleistocene changed as below: partially drycold, slightly cooldry, warmhumid, hotmoisture below, partially cooldry, colddry. The obvious influence from the Last Maximum Glaciation resulted in the difference of pollen assemblage characteristics between the Holocene and the late Pleistocene. The climate became generally warm and humid in the Holocene, but being alterated with some minor climatic fluctuation events,eg. the most obvious partial drycool transition around 2250a BP. Two transgressions have affected the delta during the late Pleistocene and the Holocene. Not only the variations of climatic and sealevel changes of two cores are consistent each other, but also a good correspondence between climate and sealevel change is shown. The differences on stratigraphy, sedimentary facies and pollen characteristics of two cores were resulted from the distinctive location, sedimentary environment and the topography of depositional bed.〗关键词：paleoclimate;pollen;sedimentation;Late Quaternary;the Pearl River Delta
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发布时间：2023-12-11 - 摘要：Organic matter types of core SB01 from the Sanshui Basin were analyzed using organic petrology method and RockEval pyrolysis. Based on organic petrology results, the organic matter is dominated by type II (including type II1 and type II2), mostly type II1. Type I organic matter intermittently occurs at some intervals while Type III organic matter is occasional in presence. Pyrolysis results show that the organic matter is of lower thermal maturity and the organic carbon loss could be ignored, as indicated by the lower Tmax values. Organic matter of Types I, II1 and II2 was deposited under arid, drier and humid climate conditions, respectively. The uppermost part of the Xinzhuang Formation is characterized by Type II1, related to a dry climatic condition. Submember A of the Honggang Member is dominated by organic Type II2, sandwiched by Type I and II1, suggesting a prevailing humid climatic condition. Submember B is characterized by alternations of organic Types II2 and II1/I, reflecting rapid fluctuations of humid and dry/arid climatic conditions. Submember C shows Type II1 and I in the lower part and shifts to Type II2 in the middle and upper parts, indicating a dry/arid climate condition followed by a prevailing humid climatic condition.关键词：organic matter types;organic petrology;rockeval pyrolysis;paleoclimate;Sanshui Basin
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发布时间：2023-12-11 - 摘要：Sensitivity analysis is an efficient approach to diagnose model structure and identify the dominant parameters controlling model behavior. It is also a key step in modeling practice. The global sensitivity of parameters of the Xinanjing model is analyzed using Extend FAST method in the Liuxihe reservoir catchment. Results show that the sensitivity of four object functions perform is different. The sensitivity can be influenced by many factors, such as the initial condition and flood type. The results are compared with the scatter map generated by the GLUE uncertainty method. Both methods can get comparable sensitivity analysis results. The main effect sensitivity and interaction effect sensitivity calculated by Extend FAST also supply quantitative indices to help understand the uncertainty in hydrological model.关键词：Extend FAST;Xinanjiang model;Global sensitivity;GLUE;uncertainty
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发布时间：2023-12-11 - 摘要：In a series of batch washing experiments, EDTA solution was used to remediate Cu contaminated soil derived from a Brown Field Site to investigate the removal efficiency of Cu as well as the release characteristics of major elements (Ca, Fe and so forth) by the application of six different EDTA dosages (0.10~6.00 mol/kg). Results showed that, with the increase of EDTA dosage, Cu removal efficiency was enhanced and reached a maximum at 400 mol/kg, accompanied by the decrease of Ca releasing and the increase of Fe and Al releasing. When 0.80 mol/kg EDTA was adopted, residual Cu concentration in the washed soil generally complied with the Environmental Quality Standard for Soils (Class Ⅲ) (GB156181995). When calculating the amount of metals washed by per mole EDTA, it was found that the molal ratio of metals to EDTA in the eluate decreased accordingly with the increase of EDTA addition. The maximum molal ratio of Cu/(K+Na+Ca+Mg+Fe+Al+Mn+Si)was obtained when 0.80 mol/kg EDTA was applied. However, this molal ratio decreased when the EDTA dosage was further increased, indicating that higher EDTA dosages were mainly used for the releasing of other metals. Thus, in this study, 0.80 mol/kg EDTA was considered as the most appropriate dosage which could not only remediate heavy metals contaminated soil to meet the national standard, but also had the best removal efficiency of Cu when compared with other metals. Conclusively, the appropriate EDTA dosages should be determined on the basis of remediation aim, with the total metal removal efficiency and molal ratio of metals to EDTA being taken into account simultaneously.
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发布时间：2023-12-11 - 摘要：The perforating triplesteel tube bucklingrestrained brace is an energy damping device with the good performance. The structure of the triplesteel tube bucklingrestrained brace is introduced in this paper. In order to research the carrying capacity and hysteretic energy performance of the perforating triplesteel tube bucklingrestrained brace for different perforating types and gaps, ten different perforating types and sizes are designed to carry out a FEM analysis with softwares ANSYS and ABAQUS. The perforating triplesteel tube bucklingrestrained brace shows a stable hysteretic function and higher energy dissipation capacity, with the yielding point in the setting area. The perforating form and size influence the functions of the perforating triplesteel tube bucklingrestrained brace. The“confinement” effect of perforating triplesteel tube bucklingrestrained brace is significantly lower than that of traditional triplesteel tube bucklingrestrained brace. The carrying capacity of BRB does not reduce when the gap is not zero.关键词：bucklingrestrained brace;triplesteel;perforation;hysteretic capacity;finite element analysis
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发布时间：2023-12-11 - 摘要：The Guangning jade is a precious type of Chinese jades, which is found in Guangning county, Guangdong province. Four types of different colored jade stones were sampled from a jade deposit. Their mineralogical characteristics were analyzed using XPD, SEM, DTA, IR and EMPA techniques. The Guangning jade is mainly composed of 2M1 sericite, and secondly chlorite. Both XPD and IR results indicate daunialite does not exist in the crystal structure of sericite. The analysis of DTG shows that the dehydroxylation tempreture of samples is beyond 600 ℃, which is different from hydromica. The microtexture of sericite shows flakeshaped, and the minerals arrange along the longaxis of crystal, interleaved by each other, showing overlapped and flake interleaved microstructure. The EMPA suggests that sericite is rich in Si、K、Al and Cr. Those rich in Cr can be grouped into Crbearing sericite.关键词：Guangning jade;sericite;mineralology
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发布时间：2023-12-11 - 摘要：The analytic expression of correlation function of free scalar field in any dimensional Euclidean space is derived by two different methods, the second of which is proposed. The results in 3 and lower dimensional space are generally discussed in the literature, and the generalized result in arbitrary dimensional space is obtained. When studying the case in 3dimensional space, people often do the integration directly in the 3dimensional space using the sphere coordinates, and this method is also applied in this paper to get the generalized result. On the other hand, it is found that choosing the appropriate coordinate system can effectively reduce the integration variable dimension and finally arrive at the same result. The result shows that the correlation function of free scalar field in any dimensional space is related to the modified Bessel function, whose order is determined by the space dimension.关键词：correlation function;reduction of integration variable dimension;Euclidean space
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发布时间：2023-12-11
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