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Impacts of Sulfur and Microalgae Co-fertilization on Saline-alkaline Soil of Sunflower Field in Hetao Irrigation District
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作者 Ruimin DONG Liming LAI +5 位作者 Peng ZHANG Yanxiong ZHAO Yang YANG Haiwei WANG Man WANG Yuelong DONG 《Asian Agricultural Research》 2023年第3期30-33,36,共5页
[Objectives]To evaluate the impacts of the elemental sulfur(S 0)and micro-algae(MA)co-fertilization on saline-alkaline soil of sunflower field in the Hetao Irrigation District(HID).[Methods]The greenhouse pot experime... [Objectives]To evaluate the impacts of the elemental sulfur(S 0)and micro-algae(MA)co-fertilization on saline-alkaline soil of sunflower field in the Hetao Irrigation District(HID).[Methods]The greenhouse pot experiment was conducted with four treatments:control(CK),single S 0 fertilization(S),single MA fertilization(A),and S 0 and MA co-fertilization(SA)for comparing the selected soil properties and sunflower plant heights and weights in different treatments.[Results]The results showed that the mean soil organic matter(SOM)under the SA(25.08 g/kg)was significantly higher than that for the CK(20.59 g/kg),S(22.47 g/kg),and A(22.95 g/kg).The mean pH under the SA(7.75)was significantly lower than that for the CK(8.14),S(7.82),and A(7.96).The mean soil exchangeable Na+concentration under the SA was significantly lower than that for the S.The mean soil electrical conductivity(EC)under the SA was 9.76%lower than that for the S.The means of Cl-(1.22 g/kg)and SO 2-4(1.90 g/kg)in soil under the SA were lower than that for the S(1.30,2.06 g/kg)and A(1.31,1.97 g/kg),respectively.For plant height 3 at the late stage of plant growth,the mean plant height 3 under the SA(89.00 cm)was higher than that of the CK(69.60 cm)and A(74.33 cm).The total weights of the fresh sunflower heads,fresh stems,and dry seeds under the SA were higher than that for the CK,S,and A.[Conclusions]In conclusion,the S 0 and MA co-fertilization had positive effects on improving saline-alkaline soils,the soil under the S 0 and MA co-fertilization could be better conditions for promoting sunflower growth than that for the S,Z,and CK,and thereby the S 0 and MA co-fertilization could be a new idea to improve saline-alkaline soil in the cold and arid regions. 展开更多
关键词 Sulfur and microalgae co-fertilization SUNFLOWER Saline-alkaline soil Hetao Irrigation District(HID)
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Reduction of the oxidative damage to H_(2)O_(2)-induced HepG2 cells via the Nrf2 signalling pathway by plant flavonoids Quercetin and Hyperoside
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作者 Meijing Zhang Gaoshuai Zhang +10 位作者 Xiangxing Meng Xinxin Wang Jiao Xie Shaoshu Wang Biao Wang Jilite Wang Suwen Liu Qun Huang Xu Yang Jing Li Hao Wang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期1864-1876,共13页
Hyperoside and quercetin are similar in molecular structures.In this study,the antioxidant regulatory targets of hyperoside and quercetin are mainly in the nuclear factor(erythroid-2-derived)-related factor 2(Nrf2)pat... Hyperoside and quercetin are similar in molecular structures.In this study,the antioxidant regulatory targets of hyperoside and quercetin are mainly in the nuclear factor(erythroid-2-derived)-related factor 2(Nrf2)pathway predicted by network pharmacology.And the antioxidant effect and mechanism of hyperoside and quercetin were measured and compared in H_(2)O_(2)-induced Hep G2 cells and Caenorhabditis elegans.The findings indicated that quercetin was more effective than hyperoside in reducing oxidative damage,which was proved by improved cell viability,decreased reactive oxygen species(ROS)production,decreased cellular apoptosis,and alleviated mitochondrial damage.In addition,quercetin was more efficient than hyperoside in enhancing the expression of Nrf2-associated m RNAs,increasing the activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),and catalase(CAT),and reducing the cellular malondialdehyde(MDA)content.Quercetin was superior to hyperoside in prolonging the lifespan of worms,decreasing the accumulation of lipofuscin,inhibiting ROS production,and increasing the proportion of skn-1 in the nucleus.With the Nrf2 inhibitor ML385,we verified that quercetin and hyperoside primarily protected the cells against oxidative damage via the Nrf2 signalling pathway.Furthermore,molecular docking and dynamics simulations demonstrated that the quercetin-Kelch-like ECH-associated protein 1(Keap1)complex was more stable than the hyperoside-Keap1 complex.The stable structure of the complex might hinder the binding of Nrf2 and Keap1 to release Nrf2 and facilitate its entry into the nucleus to play an antioxidant role.Overall,quercetin had a better antioxidant than hyperoside. 展开更多
关键词 HYPEROSIDE QUERCETIN HepG2 cell Oxidative damage Nrf2 signalling pathway
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Characteristics and Development of Agricultural Soil in Hetao Irrigation District,Inner Mongolia 被引量:1
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作者 Yang YANG Liming LAI Li MEI 《Agricultural Biotechnology》 CAS 2022年第4期77-82,共6页
Hetao Irrigation District is located in the cold and arid region of Hetao Plain,Inner Mongolia,where the agricultural soil has unique characteristics.Although the agricultural soil properties in Hetao Irrigation Distr... Hetao Irrigation District is located in the cold and arid region of Hetao Plain,Inner Mongolia,where the agricultural soil has unique characteristics.Although the agricultural soil properties in Hetao Irrigation Districts have been reported,the overall characteristics remain unclear.Through literature review and investigation,the overall characteristics,development patterns,and related reasons were explored,consequently providing theoretical support for enhancing soil utilization and formulating sustainable soil development strategies.The results showed that the agricultural soil in Hetao Irrigation District originated from the sedimentary layer and anthropogenic mellowing produced by the diversions of the Yellow River.The soil has periodic secondary salinization characteristics,accompanied by a slightly increasing pH value over time.It has low soil organic contents with a stable changing trend,low nitrogen,and phosphorus contents but high potassium and sulfur content,uneven nutrient distribution,diverse production performance,weak but stable ecological performance,and heterogeneous soil quality with a stable change trend.These findings indicate that this kind of soil can be used to plant diverse crops tolerant to different saline-alkali and requiring various nutrients.This agricultural soil is sustainable,but it is also faced with the problems of increased saline-alkali,nutrient loss,and pollution. 展开更多
关键词 Agricultural soil Secondary salinization Organic matter Soil nutrients HETEROGENEITY Ecological features Hetao Irrigation District
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An Empirical Framework of Washing Salinity by Irrigation to Maintain Soil Quality in Hetao Irrigation District
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作者 Xueao GAO Liming LAI +2 位作者 Ning LI Yang YANG Haiwei WANG 《Asian Agricultural Research》 2022年第9期28-34,共7页
[Objectives] To summarize the characteristics of washing salinity by irrigation in Hetao Irrigation District, and propose the empirical framework of washing salinity by irrigation to maintain soil quality, and provide... [Objectives] To summarize the characteristics of washing salinity by irrigation in Hetao Irrigation District, and propose the empirical framework of washing salinity by irrigation to maintain soil quality, and provide a theoretical basis for maintaining the sustainable development of soil in Hetao Irrigation District. [Methods] The methods of experiment, questionnaire, on-the-spot investigation and literature review were used. [Results] This study proposed the empirical framework of washing salinity by irrigation to maintain soil quality in Hetao Irrigation District. Seven factors of the framework, including flood irrigation, land leveling, plastic film mulching, fertilization, soil organic matter, pH and salinity, and their relationships were determined. The characteristics of these factors in Hetao Irrigation District were investigated(flooding irrigation with a large amount of irrigation water, high amount of fertilizer application, low organic matter, high pH, large variation of salinity, etc.). The mechanisms and effects of various factors affecting soil quality in Hetao Irrigation District were analyzed(the mean soil organic matter(SOM) and pH were kept in the range of 10.9-13.9 g/kg and 8.0-8.15 in recent 35 years, respectively, and increased slightly, etc.). [Conclusions] The empirical framework can be used as a theoretical norm for evaluating soil quality under the condition of washing salinity by irrigation. Under the condition of washing salinity by irrigation, the agricultural soil quality in Hetao Irrigation District showed a stable trend over time. Using this framework, we can find soil problems, and adjust some unbalanced factors to maintain the stability of soil quality in Hetao Irrigation District, and can also provide a reference for other areas. 展开更多
关键词 Washing salinity by irrigation Empirical framework Soil quality Hetao Irrigation District
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Approximate solutions to fractional differential equations
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作者 Yue LIU Zhen ZHAO +1 位作者 Yanni ZHANG Jing PANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第10期1791-1802,共12页
In this paper, the time-fractional coupled viscous Burgers' equation(CVBE)and Drinfeld-Sokolov-Wilson equation(DSWE) are solved by the Sawi transform coupled homotopy perturbation method(HPM). The approximate seri... In this paper, the time-fractional coupled viscous Burgers' equation(CVBE)and Drinfeld-Sokolov-Wilson equation(DSWE) are solved by the Sawi transform coupled homotopy perturbation method(HPM). The approximate series solutions to these two equations are obtained. Meanwhile, the absolute error between the approximate solution given in this paper and the exact solution given in the literature is analyzed. By comparison of the graphs of the function when the fractional order α takes different values, the properties of the equations are given as a conclusion. 展开更多
关键词 Caputo fractional derivative coupled viscous Burgers'equation(CVBE) Drinfeld-Sokolov-Wilson equation(DSWE) Sawi transform homotopy perturbation method(HPM)
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Fox- and raccoon-dog–associated rabies outbreaks in northern China 被引量:3
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作者 Ye Liu Shoufeng Zhang +6 位作者 Jinghui Zhao Fei Zhang Nan Li Hai Lian Wurengege Shiyu Guo Rongliang Hu 《Virologica Sinica》 SCIE CAS CSCD 2014年第5期308-310,共3页
Dear Editor,Rabies is a generally fatal disease caused by the rabies virus(RABV),and is transmitted mainly by Carnivora and Chiroptera(Fooks A R,et al.,2014;Tao X,et al.,2013).In China,stray dogs and some wild animals... Dear Editor,Rabies is a generally fatal disease caused by the rabies virus(RABV),and is transmitted mainly by Carnivora and Chiroptera(Fooks A R,et al.,2014;Tao X,et al.,2013).In China,stray dogs and some wild animals(e.g.,Chinese ferret badgers,foxes,and raccoon dogs)are the principal reservoirs for RABV(Hu R L,et al.,2009).Historically,rabies in wild foxes and raccoon dogs(Nyctereutes procyonoides)was recorded in the early 展开更多
关键词 RABIES FOX reservoirs FATAL transmitted ISOLATE CATTLE Changchun Heilongjiang surveillance
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Soil aggregation and aggregate associated organic carbon and total nitrogen under long-term contrasting soil management regimes in loess soil 被引量:16
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作者 XIE Jun-yu XU Ming-gang +4 位作者 Qiangjiu Ciren YANG Yang ZHANG Shu-lan SUN Ben-hua YANG Xue-yun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2405-2416,共12页
This study investigated the effects of three contrasting soil management regimes and different nutrient treatments on the distribution of water-stable aggregates(〉2, 1–2, 0.5–1, 0.25–0.5, and 〈0.25 mm) and asso... This study investigated the effects of three contrasting soil management regimes and different nutrient treatments on the distribution of water-stable aggregates(〉2, 1–2, 0.5–1, 0.25–0.5, and 〈0.25 mm) and associated soil organic carbon(SOC) and total nitrogen(TN) content in loess soil. A 21-yr long-term experiment was performed, in which soil management regimes include cropland abandonment(Abandonment), bare fallow(Fallow) and wheat-fallow cropping(Cropping). Under Cropping, the following nutrient treatments were employed: control(CK, no nutrient input), nitrogen only(N), nitrogen and potassium(NK), phosphorus and potassium(PK), NP, NPK, and manure(M) plus NPK(MNPK). Results demonstrated that Abandonment significantly increased the content of soil macro-aggregates(〉0.25 mm) and mean weight diameter(MWD) at 0–10 and 10–20 cm soil horizons compared with Cropping, whereas Fallow yielded lower values of above two parameters. Abandonment increased SOC and TN contents in all aggregate sizes by 17–62% and 6–60%, respectively, at 0–10 cm soil layer compared with Cropping. Conversely, Fallow decreased SOC and TN contents in all aggregates by 7–27% and 7–25%, respectively. Nevertheless, the three soil management regimes presented similar SOC contents in all aggregates at 10–20 cm soil horizon. Only Cropping showed higher TN content in 〉0.5 mm aggregates than the two other regimes. Consequently, Abandonment enhanced the partitioning proportions of SOC and TN in 〉1 mm macro-aggregates, and Fallow promoted these proportions in micro-aggregates compared with Cropping. Under Cropping, long-term fertilization did not affect the distribution of aggregates and MWD values compared with those under CK, except for NPK treatment. Fertilizer treatments enhanced SOC and TN contents in aggregates at all tested soil depths. However, fertilization did not affect the partitioning proportions of SOC and TN contents in all aggregates compared with CK. Comprehensive results showed that different soil management regimes generated varied patterns of SOC and TN sequestration in loess soil. Abandonment enhanced soil aggregation and sequestered high amounts of SOC and TN in macro-aggregates. Long-term amendment of organic manure integrated with NPK maintained soil aggregate stability and improved SOC and TN sequestration in all aggregates in loess soil subjected to dryland farming. 展开更多
关键词 cropland abandonment bare fallow wheat-fallow water-stable aggregate aggregate stability
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Comprehensive Techniques for Improving the Utilization Rate of Sows in Large-scale Pig Farms 被引量:1
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作者 Liang Yonghou Wang Gui +1 位作者 Liu Yanping Zhang Zhihong 《Animal Husbandry and Feed Science》 CAS 2018年第5期282-286,共5页
The main task of sows is to breed piglets. The reproductive performance of sows is different due to different techniques adopted in the production of pig farms, which determines the utilization rate of sows and the nu... The main task of sows is to breed piglets. The reproductive performance of sows is different due to different techniques adopted in the production of pig farms, which determines the utilization rate of sows and the number of sows in the pig farms. The article analyzed the reproductive performance of sows from the technical point of view, so that the utilization rate of sows can be paid enough attention in the production of pig farms.It is suggested that the technical training should be strengthened in pig farms to improve the corresponding technical level. Meanwhile, pig farms should make the full use of reproductive performance of sows to obtain the maximum economic benefit. 展开更多
关键词 Utilization rate of sows Reproductive performance Technical level Recessive waste Economic benefit
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tP40 carbon: A novel superhard carbon allotrope
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作者 Heng Liu Qing-Yang Fan +3 位作者 Fang Yang Xin-Hai Yu Wei Zhang Si-Ning Yun 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期392-400,共9页
In this work, a novel carbon allotrope tP40 carbon with space group P4/mmm is proposed. The structural stability, mechanical properties, elastic anisotropy, and electronic properties of tP40 carbon are investigated sy... In this work, a novel carbon allotrope tP40 carbon with space group P4/mmm is proposed. The structural stability, mechanical properties, elastic anisotropy, and electronic properties of tP40 carbon are investigated systematically by using density functional theory (DFT). The calculated elastic constants and phonon dispersion spectra indicate that the tP40 phase is a metastable carbon phase with mechanical stability and dynamic stability. The B/G ratio indicates that tP40 carbon is brittle from 0 GPa to 60 GPa, while tP40 carbon is ductile from 70 GPa to 100 GPa. Additionally, the anisotropic factors and the directional dependence of the Poisson's ratio, shear modulus, and Young's modulus of tP40 carbon at different pressures are estimated and plotted, suggesting that the tP40 carbon is elastically anisotropic. The calculated hardness values of tP40 carbon are 44.0 GPa and 40.2 GPa obtained by using Lyakhov–Oganov's model and Chen's model, respectively, which means that the tP40 carbon can be considered as a superhard material. The electronic band gap within Heyd–Scuseria–Ernzerhof hybrid functional (HSE06) is 4.130 eV, and it is found that the tP40 carbon is an indirect and wider band gap semiconductor material. 展开更多
关键词 novel carbon allotrope elastic properties ANISOTROPY superhard material
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Development of Annexin V Technology for Removal of Dead Spermatozoa from Bovine Spermatozoa and Its Application in Frozen Sexed Semen Production
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作者 Jian ZHANG Qi QI +3 位作者 Yonghou LIANG Zhimin DONG Gui WANG Xueyuan ZHOU 《Agricultural Biotechnology》 CAS 2022年第1期60-66,共7页
[Objectives]This study was conducted to develop a molecular marker immunomagnetic bead sorting technology method that can specifically identify dead spermatozoa.[Methods]This study first confirmed the specific binding... [Objectives]This study was conducted to develop a molecular marker immunomagnetic bead sorting technology method that can specifically identify dead spermatozoa.[Methods]This study first confirmed the specific binding of Annexin V to dead bovine spermatozoa,and tried to remove dead spermatozoa in semen combining with the immunomagnetic bead technology,so as to improve the separation efficiency of target spermatozoa in the process of sex-controlled semen preparation on a flow cytometer.[Results]The spermatozoon motility,membrane integrity and mitochondrial activity after sorting and the rate of dead spermatozoa during the on-machine X/Y separation were all improved to different degrees(P<0.05),indicating that the technical process design could effectively remove some dead spermatozoa,and there was no significant effect on frozen sexed semen prepared from the separated X or Y spermatozoa(P>0.05),indicating that the technical process did not cause additional damage to the spermatozoa.[Conclusions]Combining the specificity of Annexin V with the immunomagnetic bead method could effectively remove dead spermatozoa from bovine spermatozoa,and significantly reduce the rate of dead spermatozoa in bovine permatozoa during sex-controlled separation(P<0.05).The method developed can effectively improve the production efficiency of frozen sexed semen of dairy cows,reduce the production cost,and promote the industrial application of the product. 展开更多
关键词 Bovine spermatozoon Annexin V Immunomagnetic beads Frozen sexed semen
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C2-Si:a Novel Silicon Allotrope in Monoclinic Phase
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作者 Qing-yang Fan Yi-chao Sun +3 位作者 Fang Yang Yan-xing Song Xin-hai Yu Si-ning Yun 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第6期945-956,I0073,共13页
Based on density functional theory(DFT),a new silicon allotrope C2-Si is proposed in this work.The mechanical stability and dynamic stability of C2-Si are examined based on the elastic constants and phonon spectrum.Ac... Based on density functional theory(DFT),a new silicon allotrope C2-Si is proposed in this work.The mechanical stability and dynamic stability of C2-Si are examined based on the elastic constants and phonon spectrum.According to the ratio of bulk modulus and shear modulus,C2-Si has ductility under ambient pressure;compared with Si_(64),Si_(96),I4/mmm and h-Si6,C2-Si is less brittle.Within the Heyd-Scuseria-Ernzerhof(HSE06)hybrid functional,C2-Si is an indirect narrow band gap semiconductor,and the band gap of C2-Si is only 0.716 eV,which is approximately two-thirds of c-Si.The ratios of the maximum and minimum values of the Young’s modulus,shear modulus and Poisson’s ratio in their 3D spatial distributions for C2-Si are determined to characterize the anisotropy.In addition,the anisotropy in different crystal planes is also investigated via 2D representations of the Young’s modulus,shear modulus,and Poisson’s ratio.Among more than ten silicon allotropes,C2-Si has the strongest absorption ability for visible light. 展开更多
关键词 Silicon allotrope ANISOTROPY Narrow band gap Elastic constant
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Synergistic Effects of 18β-glycyrrhetinic Acid Combined with Antituberculosis Drugs against Mycobacterium tuberculosis
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作者 Jia Fang Xing Liqun 《Animal Husbandry and Feed Science》 CAS 2015年第1期46-49,共4页
The in vitro antibacterial activities of 18β-glycyrrhetinic acid alone or combined with first-line antituberculosis drugs including isoniazid(INH),rifampicin(RFP) and streptomycin(SM) against Mycobacterium tube... The in vitro antibacterial activities of 18β-glycyrrhetinic acid alone or combined with first-line antituberculosis drugs including isoniazid(INH),rifampicin(RFP) and streptomycin(SM) against Mycobacterium tuberculosis were detected using MABA method.The minimum inhibitory concentrations(MICs) of18β-glycyrrhetinic acid against M.tuberculosis H37Rv(ATCC 27294) and M.bovis(ATCC 19210) were 50 and 100 μg/m L,respectively.The MICs of two clinical drug-susceptible isolates and six drug-resistant isolates were 25-50 and 100-200 μg/m L,respectively.As 18β-glycyrrhetinic acid combined with INH,RFP and SM,they exhibited synergistic effects against six drug-resistant isolates,and MICs decreased significantly:MIC of INH decreased by 2-32 folds(FICIs 0.125-0.375);MIC of RFP decreased by 4-8 folds(FICIs 0.240-0.490);MIC of SM decreased by 4-16 folds(FICIs 0.165-0.460).Traditional medicine monomer had low cytotoxicity on normal cell BHK-21 and could restraint SMMC fission.The results showed that 18β-glycyrrhetinic acid combined with anti-TB drugs(INH,RFP and SM) had good antibacterial activity against M.tuberculosis.These findings indicated that 18β-glycyrrhetinic acid might serve as the potential therapeutic compound for future development of anti-TB drugs. 展开更多
关键词 18β-glycyrrhetinic acid Antituberculosis(Anti-TB) drugs Mycobacterium tuberculosis Minimum inhibitory concentration(MIC)
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Initial Analysis on the Legal Protection of Consumers' Rights and Interests in Network Transaction
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作者 Xiaoqing Ren 《International Journal of Technology Management》 2016年第7期5-7,共3页
With the development of network technology and information technology, electronic commerce as a new business model wiht itsnew trading ideas-+, In changing the traditional business structure,but also gradually changi... With the development of network technology and information technology, electronic commerce as a new business model wiht itsnew trading ideas-+, In changing the traditional business structure,but also gradually changing people’s shopping patterns and consumptionpatterns,Online shopping has become the preferred way of shopping.Changes in consumption patterns will inevitably lead to new problems inthe process of consumption,and the development speed of the problem in sync with the development speed of network economy,as far as therenewal speed of laws and regulations is concerned,this asymmetric development is bound to bring great inconvenience to the consumer rights innetwork transactions.In this paper, from the angle of legal protection,the protection of consumer rights and interests in network transactions areexpounded,analysis of the current situation and reasons of the consumers’ rights and interests are infringed upon in the network transaction,learnfrom the experience of foreign consumer rights and interests protection,In order to put forward effective suggestions on the system constructionof the protection of consumer rights and interests. 展开更多
关键词 network transaction consumer’s rights and interests legal prote
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Symplectic Self-adjointness of Infinite Dimensional Hamiltonian Operators 被引量:1
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作者 Lin LI Alatancang CHEN De Yu WU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2018年第9期1473-1484,共12页
Symplectic self-adjointness of infinite dimensional Hamiltonian operators is studied, the necessary and sufficient conditions are given. Using the relatively bounded perturbation, the sufficient conditions about sympl... Symplectic self-adjointness of infinite dimensional Hamiltonian operators is studied, the necessary and sufficient conditions are given. Using the relatively bounded perturbation, the sufficient conditions about symplectic self-adjointness are shown. 展开更多
关键词 Hamiltonian operator symplectic self-adjointness quadratic complement relative bound
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Land cover change and multiple remotely sensed datasets consistency in China
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作者 Hui Wang Liping Cai +2 位作者 Xiaojin Wen Donglin Fan Yuejun Wang 《Ecosystem Health and Sustainability》 SCIE 2022年第1期35-49,共15页
Introduction:Although numerous land cover datasets can act as references for understanding land cover change in China,the inconsistencies between the datasets can also provide understanding.Previous studies on the con... Introduction:Although numerous land cover datasets can act as references for understanding land cover change in China,the inconsistencies between the datasets can also provide understanding.Previous studies on the consistency between land cover datasets have mostly focused on land cover type consistencies and have ignored data consistencies in land cover change.Outcomes:Therefore,we aim to analyse the consistencies in land cover changes through likelihood assessment methods.We compared the spatiotemporal changes in forest,grassland,cropland,and bare land in the Climate Change Initiative land cover dataset(CCI-LC),Moderateresolution Resolution Imaging Spectroradiometer land cover dataset(MCD12Q1),China’s National Land Use and Cover Change(CNLUCC),Globeland30 and Global Land Cover Fine Surface Covering 30(GLC-FCS30)datasets in 2010.The results showed that the percentages and changes in each land cover type in MCD12Q1 were different from those in the other datasets.Discussion:For example,the proportion of grassland in MCD12Q1 was the highest,reaching 48.04%.The places with high consistency were the places where the land cover types were concentrated,and the bare land had the highest consistency.However,the consistency of China’s land cover change was quite low,and the percentage of low consistency was more than 87%from 2000-2018.Comparison of the data with the global artificial impervious area(GAIA)and Hansen-Global Forest Change(Hansen-GFC)datasets showed that the percentage of high construction gain consistency(38.83%)was higher than the forest change consistency,and the percentage forest loss high consistency(8.85%)was lower than the forest gain high consistency(12.76%).Conclusion:The results not only provide a basis for the use of land cover datasets but also give a clearer understanding of the pattern of land cover changes. 展开更多
关键词 Spatiotemporal characteristic MCD12Q1 CCI-LC consistency assessment RMSE
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P2_(1)3 BN:a novel large-cell boron nitride polymorph
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作者 Qing-Yang Fan Nan Wu +4 位作者 Shuai-Ming Chen Li Jiang Wei Zhang Xin-Hai Yu Si-Ning Yun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第12期159-167,共9页
A new boron nitride polymorph,P2_(1)3 BN(space group:P2_(1)3),is investigated by first-principles calculations,including its structural properties,stability,elastic properties,anisotropy and electronic properties.It i... A new boron nitride polymorph,P2_(1)3 BN(space group:P2_(1)3),is investigated by first-principles calculations,including its structural properties,stability,elastic properties,anisotropy and electronic properties.It is found that the new boron nitride polymorph P2_(1)3 BN is mechanically,dynamically and thermodynamically stable.The bulk modulus(B),shear modulus(G)and Young’s modulus of P2_(1)3 BN are 91 GPa,41 GPa and 107 GPa,respectively,all of which are larger than that of Y carbon and TY carbon.By comparing with c-BN,the Young’s modulus,shear modulus and Poisson’s ratio of P2_(1)3 BN show tiny anisotropy in the(001),(010),(100)and(111)planes.At the same time,in contrast with most boron nitride polymorphs,P2_(1)3 BN is a semiconductor material with a smaller band gap of 1.826 eV.The Debye temperature and the anisotropic sound velocities of P2_(1)3 BN are also investigated in this work. 展开更多
关键词 boron nitride polymorph elastic properties ANISOTROPY electronic properties
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Pressure Oscillating Flow in Corrugated Parallel Channel
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作者 Yu-Fei Wei Hai-Jun Wang Yong-Jun Jian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第12期694-700,共7页
The approximate analytical solution of velocity is presented for incompressible and viscous fluid driven by the oscillation of the periodic pressure, between two slit parallel plates with corrugated walls by employing... The approximate analytical solution of velocity is presented for incompressible and viscous fluid driven by the oscillation of the periodic pressure, between two slit parallel plates with corrugated walls by employing perturbation method. The corrugations of the two walls are described as periodic sinusoidal waves with small amplitude either in phase or half-period out of phase. Based on the analysis, we discuss the influence of the dimensionless parameters on velocity u±and mean velocity parameter φ±numerically, such as Reynolds number Re, nondimensional amplitude A of pressure gradient and wave number k. 展开更多
关键词 corrugated walls perturbation method oscillating pressure
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