最新刊期
卷 56 ， 期 6 ， 2017
- 摘要：The widespread Cenozoic magmatism in the Red RiverAilaoshan tectonic zone is closely related to the IndianEurasian plate collision orogeny. Zircon UPb dating results of two granitic samples exposed in the middle part of the Ailaoshan metamorphic belt are 26.2 ± 0.5 Ma and 26.8 ± 0.5 Ma, respectively. This indicates that the Ailaoshan metamorphic zone is not entirely attributed to the Proterozoic crystalline basement of the Yangtze block, while it also contains Cenozoic magmatic rocks. Zircon εHf(t)values of the samples range from +0.3 to +6.9 and from -9.8 to -0.7 with mean values of +3.4 and -4.3, respectively and their corresponding twostage Hf model ages TDM2range from 526 to 853 Ma and from 903 to 1 355 Ma. The high εHf(t) granites were derived from partial melting of juvenile crust induced by the asthenospheric mantle heat source, while low εHf(t) granites from Proterozoic metamorphic sandstones of the Ailaoshan group. In combination with previous research results, we suggest that the Red River fault has cut across the lithosphere mantle. In SE Asia, the Gaoligongshan and Ailaoshan strikeslip shear zones on both sides of Indosinian block dismembered different blocks and created conditions for their Oligocene extrusion to the southeast.关键词：Ailaoshan tectonic zone;granitic rocks;zircon ages;Hf isotope;strike slip shear;extrusion effect
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发布时间：2023-12-11 - 摘要：The Mituosi(MTS) profile in Yunxian, Hubei of China was served to investigate pedostratigraphy and sedimentary characteristics of the first river terrace of the upper Hanjiang river. Magnetic susceptibility, grainsize distribution, loss on ignition and Rb/Sr were analyzed. The MTS profile recorded the environmental evolution with the stratigraphic series from bottom to top: Malan Loess (L1)→ Transitional Loess (Lt)→ Paleosol (S0)→ Holocene Loess (L0)→ Top soil (TS). Different stratigraphic units show different degree of weathering intensity, with S0>Lt>L0>L1. The weathering intensity change of MTS profile indicates the climate change since Malan loess accumulation. It was cold and arid with gradually intensified southeast monsoon during the early Holocene. The strongest monsoon occurred in the midHolocene. During the late Holocene, the climate became drying with the monsoon recession. A cold climate event was recorded in MTS profile, dating to around 6.48 Ka BP (OSL dating).关键词：pedogenesis;climate change;loess-paleosol;upper Hanjiang river
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发布时间：2023-12-11 - 摘要：Based on the daily temperature data of 53 stations in the North China Plain from 1961 to 2014, the characteristics of temperature change of 24 solar terms are analyzed by using the trend feature index, Mann-Kendall mutation test, moving T-test and spatial interpolation. The results show that: ① The temperature of 24 solar terms presents a quasi-normal unimodal distribution, and the highest average temperature in a year occurred during Great Heat (30.4 ℃), the minimum average temperature occurred during Greater Cold (7.5 ℃). The temperature fluctuated largely during the days around Pure Brightness and Beginning of Winter. The average temperature showed an increasing trend during 24 solar terms, especially during the spring type solar terms. ② The spring type solar terms became warming in 1990s, and the summer and autumn type solar terms were cool in 1980s and 1970s and became warming after 1990s. The winter type solar terms were cool before 1990s, and the temperature increased obviously during 1990s and 2010s. ③ The average temperature of the Waking of Insects showed a significant warming trend, with a warming rate of 0.459 ℃/10a, and a warm mutation occurred in 1998. The average temperature of the Pure Brightness increased, with a warming rate of 0.43 ℃/10a, and the temperature mutation happened in 1998. The average temperature of the Lesser Fullness of Grain showed a weak trend, with a warming rate of 0.12 ℃/10a. There was no obvious mutation in the past 54 years. The annual average temperature of the Grain in Ear is on the rise, with a warming rate of 0.16 ℃/10a, and the mutation happened in 1998. ④ In the past 54 years, the spatial characteristics of the average temperature of the Waking of Insects and Pure Brightness showed that the temperature in the north of the North China Plain was lower than that in the south of the Plain, and the highest temperature and the lowest temperature appear in Xinyang and Zhangbei, respectively. The spatial characteristics of the average temperature of the Lesser Fullness of Grain and Grain in Ear showed that the temperature in the north and east of the North China Plain was lower than that in the middle and south of the plain, and the highest temperature and the lowest temperature appear in Jinan and Taishan, respectively.关键词：twenty-four solar terms;temperature variation;mutation detecting;spatial difference;the North China Plain
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发布时间：2023-12-11 - 摘要：A mathematical model of hyperbaric oxygen therapy for chronic wound healing is studied. This model contains a nonlinear secondorder parabolic equation describing the concentration of oxygen diffusion，a nonlinear first-order hyperbolic equation for capillary tip density and an ordinary differential equation for blood vessel density. The existence and uniqueness of the global solution is proved by applying the characteristic theory of hyperbolic equation, the Lp-theory，Holder-estimate theory and Banach fixed point theorem.关键词：hyperbaric oxygen therapy;chronic wound;local solution;global solution;existence and uniqueness
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发布时间：2023-12-11 - 摘要：The existence of non-constant positive solutions for a new predator-prey model with cross-diffusion is studied. Firstly, a priori estimate of positive solutions is given. Then, the existence of non-constant positive solutions is given by using degree theory. The result shows that for fixed cross-diffusion coefficients, the predator and prey can coexist when the growth rates of them are controlled in a certain range.关键词：predator-prey model;cross-diffusion;a priori estimate;degree theory;coexistence
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发布时间：2023-12-11 - 摘要：Multiple trees with set-ordered Felicitous property are coupled with a vertex on set-ordered graceful trees, and a larger composite tree is constructed. It is shown that, the composite tree has set-ordered Felicitous property.关键词：composite trees;set-ordered felicitous labelling;set-ordered graceful labelling
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发布时间：2023-12-11 - 摘要：The convergence rate of a Newman-α type rational operator approximating a class of nonsmooth functions is studied, and the exact approximation order of the rational function under the group of trigonometric functions is given. The result is superior to the case when the node group is taken as the first and the second Chebyshev nodes group, the rational interpolation of equidistant nodes group and so on.关键词：rational interpolation;Newman-αtype rational operators;order of approximation
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发布时间：2023-12-11 - 摘要：The equivalence of two mixed type functional equations in Banach space is given. By using the fixed point method, the stability of the mixed functional equation in Banach space is built up step by step. Furthermore, the better upper bound is gotten.关键词：mixed functional equation;generalized Hyers-Ulam-Rassias stability;fixed point alternative
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发布时间：2023-12-11 - 摘要：Under the framework of nonlinear expectations，the minimal members of convex expectations with some dominating conditions are studied in the view of the Sandwich theorem for a convex expectation and a concave expectation. The conclusions of the minimal members of convex expectations with single or two dominating conditions are proved to be equivalent to the Sandwich theorem.关键词：nonlinear expectation;convex expectation;Sandwich theorem;minimal member
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发布时间：2023-12-11 - 摘要：In order to mimic the in vivo 3D micro environment and compare proliferation rate of adipose derived stem cells (ADSCs) on 2D and 3D aligned nanofiber sheets, 3D aligned poly(caprolactone) (PCL) fiber scaffolds were prepared by improving the collector for electrospinning. The fibers were around capillaries in diameter of 300 μm, which were aligned very well and with fiber diameter in the range of 300~400 nm. After surface modification, ADSCs were seeded and it was found these cells were spread very well. Regardless 2D or 3D scaffolds, on aligned fibers cells were nearly all aligned along the fiber direction. When compared with that on 2D membranes, cells proliferated faster on 3D fiber scaffolds, showing the higher potential of 3D fiber scaffolds to be applied for tissue engineering applications.关键词：three-dimensional oriented fibers;electrospinning;adipose derived stem cells;bone tissue engineering
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发布时间：2023-12-11 - 摘要：The deep metro excavation will lead to the deformation of adjacent pipelines. Knowing the influence of excavation construction on pipelines has significant meanings for controlling the deformation of pipelines effectively and reducing construction risks. Based on the actual measurement data of some excavation of Xiamen line 1, parametric analysis is applied to the influence of excavation on adjacent pipelines by using the finite element method with the consideration of soil small strain stiffness characteristics. The influential zone of adjacent pipelines is divided combined with control standards on deformation. The study shows that burial depth of pipelines, compared to the horizontal distance of which from excavation, has a larger influence to the maximum settlement of pipelines. The maximum deformation of pipelines has considerable correlation to stratum deformation outside the excavation. The stiffness between pipeline and soil has limited restrictions to the soil displacement. The axial force will increase as the horizon distance from excavation declines. The larger axis stiffness and sectional area are, the bigger the axial force is. With overall consideration of pipelines horizontal distance, burial depth and other factors, the influence of excavation on adjacent pipelines can be divided into main influence area(Ⅰ), minor influence area(Ⅱ), general influence area(Ⅲ) and weak influence area(Ⅳ).关键词：HS small model(HSS);metro engineering;deep foundation pit;pipeline;numerical simulation;partition of impact
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发布时间：2023-12-11 - 摘要：In geotechnical engineering, agricultural engineering and hydraulic and hydro-Power Engineering etc., many problems such as long-term stability of dam and slope, could be regarded as the plane strain issue. Hence, these questions are always figured out though as the plane creep tests, which are more suitable to the engineering conditions. In order to deeply investigate the plane creep properties of loess soil, a series of laboratory consolidated plane creep tests of loess are conducted by a reformed plane creepmeter in this paper, and the tests results show that the deformation of plane creep is dramatic under high water content, high deviatoric stress and low consolidation condition. Base on the analysis of experimental data, a new empirical model is proposed. In addition, it is found that the two existed models named SinghMitchell and Mesri models, which are usually utilized to model the creep problems of soils, are not suitable for loess in the plane strain condition. However, the model proposed in this paper can better describe the creep proprieties of loess in the plane strain condition, due to its merits in both higher accuracy and fewer parameters.关键词：loess;plane creep;creep model
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发布时间：2023-12-11 - 摘要：The geometry structures, electronic properties and hydrogen storage properties of Si5and Li2Si5clusters are investigated by using the hybrid density functional theory (DFT) B3LYP method at 6.311+G(d, p) set basis level. Our results indicate that the lowest energy structure of Si5cluster is a three-dimensional cage, and it can not efficiently store hydrogen molecules for Si5cage by the same method. It will remarkably improve the hydrogen storage capacity coated by Li atoms. The Si5cage coated by two Li atoms (Li2Si5) can store up to 10 H2molecules, in which every Li atom can efficiently adsorb five H2molecules, corresponding to a maximum mass fraction of 11.554% with an average adsorption energies of 7.259~11.330 kJ/mol per H2molecule. The results demonstrate that Li decorated Si5cage can serve as an ideal hydrogen storage material under ambient conditions.关键词：Li2Si5·nH2clusters;density functional theory(DFT);electronic properties;adsorption energy;hydrogen storage properties
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发布时间：2023-12-11 - 摘要：The Big Bang-Big Crunch (BB-BC) algorithm is an optimization technique of swarm intelligence based on the Big Bang theory. It runs efficiently and can be realized simply, but it is easily trapped in local optimal results. For the purpose of overcoming its shortages, an improved BB-BC algorithm is put forward in this essay, with the changes of the reduced forms of blast radius, the distribution of the random variable, and the treatment of the boundary conditions. Besides, the improved algorithm is applied in damage detection of a simply supported beam with 10 and 20 elements respectively. The numerical simulations indicate that the identified results are excellent even in the great influence of noise, especially for successive elements with tiny damage. A conclusion can be drawn that the improved BBBC algorithm can precisely detect structure damage, and would not be easily trapped into local optimal.关键词：swarm intelligence;BB-BC;damage detection;frequency domain
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发布时间：2023-12-11 - 摘要：PPR were prepared with supported β-nucleating agent in this paper, the isothermal crystallization behavior and melting characteristics of PPR and β-PPR were studied with Differential Scanning Calorimeter (DSC). The isothermal crystallization kinetics of PPR and β-PPR were examined by Avrami model. It is indicated that the addition of supported β-nucleating agent improve the crystallization rate of PPR apparently and shorten the half crystallization time. Furthermore, the isothermal crystallization behavior of β-PPR depend little on the crystallization temperature and it mainly formed β-crystal. It is apt to form β-crystal for PPR when crystallization at low temperature.
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发布时间：2023-12-11 - 摘要：Litopenaeus vannamei is a major farmed shrimp species in the world, suffering serious losses because of hepatopancreas necrosis syndrome (HPNS) in recent years. The outbreak of HPNS is believed to be correlated with toxic chemical and physical factors as well as opportunistic pathogens. In 2015, we detected the concentration of ammonia, nitrite and nitrate nitrogen in 43 shrimp ponds of a aquaculture farm in Dianbai county, Guangdong province, China. In the first 22 days of breeding, the concentration of ammonia nitrogen ranged from 0.01 to 0.30 mg·L-1while nitrite nitrogen was below 0.01 mg·L-1. The concentration of nitrate nitrogen ranged from 0.01 to 0.60 mg·L-1with a similar tendency to that of ammonia nitrogen. During 22 to 72 days of breeding, the concentration of ammonia nitrogen increased from 0.30 mg·L-1to 1.50 mg·L-1in volatility. Unlike ammonia nitrogen, the nitrite nitrogen and nitrate nitrogen were generally stable, slowly and synchronously rising from 0.01 mg·L-1to 0.80 mg·L-1. After 72 days of breeding, their concentration all enhanced and fluctuated between 0.60 mg·L-1and 1.50 mg·L-1. Compared with the change of nitrite nitrogen, the sharp fluctuation of ammonia nitrogen was occurred about 26 days in advance. Moreover, we also detected the concentration of ammonia nitrogen after the zeolite and fertilizer were added in five shrimp ponds during breeding. The concentration of ammonia nitrogen was reduced by 19.50% at 1 day and reduced by 37.54% at 2 days after fertilizer addition. After adding zeolite powder, ammonia nitrogen was decreased by 47.62%，23.34%，60.73% and 76.58% in 4 days,respectively. Results also showed that the feed amount was positive correlated with the concentration of ammonia, nitrite and nitrate nitrogen (P<0.01). In summary, this study showed that the ammonia nitrogen was the limiting factor in closed culture of L. vannamei during the middle and late culture period, greatly influenced by climate. Besides, nitrite nitrogen was the restrictive factor, especially in the late culture period. Considering the tendency of ammonia nitrogen and nitrite nitrogen, the ecological system of closed shrimp culture mode can be divided into early ecosystem, medium ecosystem and late ecosystem.关键词：Litopenaeus vannamei;ammonia nitrogen;nitrite nitrogen;nitrate nitrogen
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发布时间：2023-12-11 - 摘要：The HPLC method was established for determination of Calycosin-7-O-β-D-glucoside and Calycosin in Bufeihuoxue Capsules. The separation was performed on Hitachi High-Tech C18(5 μm，4.6 mm×250 mm) column eluted with the mobile phase consisting of acetonitrile and 02% formic acid solution in gradient elution mode at the flow rate of 0.8 mL/min. The detection wavelength was 260 nm and the column temperature was 25 ℃. The method was validated and shown that Calycosin-7-O-β-D-glucoside and Calycosin had a good linear relationship in the range of 0.022 5~0.901 8 μg (R2=1), 0.007 5~0.299 0 μg(R2=1), respectively. The average recovery rates were 93.87% (RSD=3.46%)、90.04% ( RSD=3.25%), respectively. The established method is simple, rapid and reproducible, which is suitable for the determination of Calycosin-7-O-β-D-glucoside and Calycosin from Bufeihuoxue Capsules.关键词：high performance liquid chromatography;Bufeihuoxue Capsule;Calycosin-7-O-β-D-glucoside;Calycosin;determination
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发布时间：2023-12-11 - 摘要：In order to investigate the hypoglycemic effect of Ophiopogonis japonicas oligosaccharide on type 2 diabetes mellitus，the db/db diabetic mice were intragastrically administered with Ophiopogonis japonicas oligosaccharide for 8 weeks．The body weight and general physical signs were observed during the treatment．The fasting blood glucose levels were determined after 4 and 8 weeks of administration．The changes in 24 h urinary albumin excretion and 24 h urine protein amounts, glycosylated serum protein(GSP), total cholesterol(TC), triglyceride(TG), high density lipoprotein cholesterol(HDL-C) and low density lipoprotein cholesterol(LDL-C), urea nitrogen and creatinine levels in serum were measured after 8 weeks of treatment．Results showed that Ophiopogonis japonicas oligosaccharide could significantly lower the body weights, blood glucose levels and the AUCs during oral glucose tolerance test, and inhibited the changes of 24 h urinary albumin excretion and 24 h urine protein amounts, GSP, TC, TG, HDL-C and LDL-C, urea nitrogen and creatinine levels in serum of db/db diabetic mice by comparison with db/m mice. In conclusion, Ophiopogonis japonicas oligosaccharide exerts remarkable hypoglycemic and protective effects in db/db mice, thus showing its potential for use in the treatment of type 2 diabetes mellitus.关键词：Ophiopogonis japonicas oligosaccharide;type 2 diabetes mellitus;db/db mice;hypoglycemic effect
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发布时间：2023-12-11 - 摘要：To investigate the primary neurons autophagy and apoptosis after Oxygen Glucose Deprivation/Re-oxygenation (OGD/R), and to explore the effect of mild hypothermia on autophagy and apoptosis, following methods were used: Primary neurons culture and OGD/R model was established; the neurons were divided into the normal temperature group (37 ℃) and the mild hypothermia group (MH, 34 ℃); The cells viability were measured by CCK8; cell apoptosis were measured by TUNEL; The protein expressions of Sirt1, Foxo1, p53, Rab7 and autophagy related genes such as Beclin1, LC3 were detected by western blot at each time point; The neurons autophagy flows were detected through transfection of adenovirus mRFP-GFP-LC3. The primary neuron cultures were successfully developed, and the OGD/R models were established; Westernblot showed that the expressions of Sirt1, P-Foxo1, Rab7, Beclin1 and LC3b/LC3a were gradually reduced, especially at 12 h after OGD/R, P<0.05; However, the expression of p53 was increased, P<0.05; In MH group, the expressions of Sirt1, P-Foxo1, Rab7, Beclin1, LC3b/LC3a were obviously higher than those in NT group, P<0.05; And the expression of p53 was obviously lower than that in NT group, P<0.05; in R6 h+MH group， the rate of neuron cells apoptosis were 20%±6.7%, lower than 56.8%±7.6% in R6 h+NT group, P<0.05; mRFPGFPLC3 adenovirus was transfected into primary neurons, the autophagy flow was detected by fluorescence microscopy. Compared with control group, the autolysosomes were reduced, but autophagosomes were increased after OGD/R, P<0.05; however, compared with NT group, the autophagosomes were reduced and the autolysosomes were increased in MH group, P<0.05. In conclusion, mild hypothermia therapy could increase the expression of Sirt1, Foxo1, beclin1 and LC3b/LC3a, but decrease the expression of p53, so as to promote autophagy and reduce apoptosis.关键词：mild hypothermia;Sirt1;neurons
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发布时间：2023-12-11 - 摘要：Thrips hawaiiensis is an important flower inhabiting thrip pest, widely distributed in the Asian regions. The development, survival and oviposition of T. hawaiiensis on four flower hosts (Rosa rugose, Tulipa gesneriana, Dianthus caryophyllus and Lilium brownie var. viridulum) were studied in this paper, in order to discuss the damage difference and damage mechanism to different plant hosts. The results showed that the shortest developmental period of T. hawaiiensis was on Rosa rugose flower, which needed 10.07 d to complete one generation. The longest was on Lilium brownie var. viridulum flower, which needed 11.22 d to complete one generation. The highest survival rate was on T. gesneriana flower, while the lowest was on D. caryophyllus flower, with the values of 0.76 and 0.64, respectively. According to different treatments for oviposition in short time, we found that T. gesnerian flower was the most preferred host for oviposition by T. hawaiiensis, while Lilium brownie var. viridulum flower was the least preferred host. In summary, according to the performance of development, survival and oviposition of T. hawaiiensis on the four flower hosts, T. gesnerianawas the most suitable host for T. hawaiiensis, while L. browniivar. viridulum was the least.关键词：Thrips hawaiiensis;flower plant host;development;survival;oviposition
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发布时间：2023-12-11 - 摘要：A DJ strain with a high efficience of feather-degrading capability was isolated from the soil of feather waste by the enrichment culture and the screening process．The strain was identified as Streptomyces sp. according to morphologic observation, 16S rDNA sequence alignment, and phylogenetic trees analysis. After fermenting at 32 ℃ for 10 days, the feather degradation rate reached 50%, and the feather hydrolysate was found to contain amino acids. The protease produced by the DJ strain had a maximal activity at 45 ℃, and the optimum reactive pH at 10.0. The protease displayed a higher hydrolysis activity to feather than Alcalase and Papain, and had a strong hydrolysis ability to the hydrophobic or hydrophilic natural substrates. The results indicated that the DJ strain and its protease was of potential application prospects．关键词：feather-degrading Streptomyces sp. DJ strian;isolation and identification;characteristics of proteinases
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