维普中文期刊产品整合服务
167篇 您的检索式:作者名="Xintong"
    题名 作者 年代 出处 被引量
1BiVO_(4),Bi_(2)WO_(6) and Bi_(2)MoO_(6) photocatalysis:A brief review显示文摘In recent years,photocatalytic technologies have been extensively studied and diffusely used in water splitting,decomposition of organic pollutants,reduction of carbon dioxide,etc.As a type of eye-catching semiconductors,BiVO_(4),Bi_(2)WO_(6),and Bi_(2)MoO_(6) (denoted as BiaAOb)have become a hotspot in photocatalytic researches due to their crystal structure stability,high light quantum and electronic transmission efficiency,and outstanding energy utilization capacity.However,pristine BiaAOb(A=V,W,and Mo)possesses several drawbacks,such as low separation efficiency of photo-excited electron-hole pairs,low specific surface area,as well as the poor quantum utilization,which restrict their photocatalytic performance.Considerable efforts,such as nanostructure modification,surface engineering,and heterojunction/homojunction fabrication,have been conducted to solve these problems.This integrated review aims to sum up recent advances in current studies on fabrication of high efficiency BiaAOb photocatalysts to accelerate the developments of BiaAOb-based materials in the photocatalysis(PC)field.The current challenges and prospects of BiaAOb are emphasized which stretches the existing fundamental theories of PC as well as provide a promising strategy to fabricate high efficiency BiaAOb catalysts to control environmental pollution and assist the sustainable development of energy.Xintong Liu Shaonan Gu Yanjun Zhao Guowei Zhou Wenjun Li 2020Journal of Materials Science & Technology2020,56,21:13
2A detached petal disc assay and virus-induced gene silencing facilitate the study of Botrytis cinerea resistance in rose flowers显示文摘Fresh-cut roses(Rosa hybrida)are one of the most important ornamental crops worldwide,with annual trade in the billions of dollars.Gray mold disease caused by the pathogen Botrytis cinerea is the most serious fungal threat to cut roses,causing extensive postharvest losses.In this study,we optimized a detached petal disc assay(DPDA)for artificial B.cinerea inoculation and quantification of disease symptoms in rose petals.Furthermore,as the identification of rose genes involved in B.cinerea resistance could provide useful genetic and genomic resources,we devised a virusinduced gene silencing(VIGS)procedure for the functional analysis of B.cinerea resistance genes in rose petals.We used RhPR10.1 as a reporter of silencing efficiency and found that the rose cultivar‘Samantha’showed the greatest decrease in RhPR10.1 expression among the cultivars tested.To determine whether jasmonic acid and ethylene are required for B.cinerea resistance in rose petals,we used VIGS to silence the expression of RhLOX5 and RhEIN3(encoding a jasmonic acid biosynthesis pathway protein and an ethylene regulatory protein,respectively)and found that petal susceptibility to B.cinerea was affected.Finally,a VIGS screen of B.cinerea-induced rose transcription factors demonstrated the potential benefits of this method for the high-throughput identification of gene function in B.cinerea resistance.Collectively,our data show that the combination of the DPDA and VIGS is a reliable and highthroughput method for studying B.cinerea resistance in rose.Xiaoqian Cao Huijun Yan Xintong Liu Dandan Li Mengjie Sui Jie Wu Hongqiang Yu Zhao Zhang 2019Horticulture Research2019,6,1:5
3Blockchain-enabled wireless communications:a new paradigm towards 6G显示文摘With the deployment of fifth-generation(5 G)wireless networks worldwide,research on sixth-generation(6 G)wireless communications has commenced.It is expected that 6 G networks can accommodate numerous heterogeneous devices and infrastructures with enhanced efficiency and security over diverse,e.g.spectrum,computing and storage,resources.However,this goal is impeded by a number of trust-related issues that are often neglected in network designs.Blockchain,as an innovative and revolutionary technology that has arisen in the recent decade,provides a promising solution.Building on its nature of decentralization,transparency,anonymity,immutability,traceability and resiliency,blockchain can establish cooperative trust among separate network entities and facilitate,e.g.efficient resource sharing,trusted data interaction,secure access control,privacy protection,and tracing,certification and supervision functionalities for wireless networks,thus presenting a new paradigm towards 6 G.This paper is dedicated to blockchain-enabled wireless communication technologies.We first provide a brief introduction to the fundamentals of blockchain,and then we conduct a comprehensive investigation of the most recent efforts in incorporating blockchain into wireless communications from several aspects.Importantly,we further propose a unified framework of the blockchain radio access network(B-RAN)as a trustworthy and secure paradigm for 6 G networking by utilizing blockchain technologies with enhanced efficiency and security.The critical elements of B-RAN,such as consensus mechanisms,smart contract,trustworthy access,mathematical modeling,cross-network sharing,data tracking and auditing and intelligent networking,are elaborated.We also provide the prototype design of B-RAN along with the latest experimental results.Jiaheng Wang Xintong Ling Yuwei Le Yongming Huang Xiaohu You 2021National Science Review2021,8,9:4
4Increasing the efficiency of CRISPR/Cas9-based gene editing by suppressing RNAi in plants显示文摘Dear Editor,CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated)-based genome editing is a powerful and widely adopted technology for introducing specific mutations in animal and plant systems.Xiaoyan Wang Jiayun Lu Kangwen Lao Suikang Wang Xiaowei Mo Xintong Xu Xuemei Chen Beixin Mo 2019Science China(Life Sciences)2019,62,7:4
5Experimental continuous sludge microwave system to enhance dehydration ability and hydrogen production from anaerobic digestion of sludge显示文摘Dehydrating large amounts of sludge produced by sewage treatment plants is difficult.Microwave pretreatment can effectively and significantly improve the dewaterability and hydrogen production of sludge subjected to anaerobic digestion. The aim of this study was to investigate the effects of different microwave conditions on hydrogen production from anaerobic digestion and dewaterability of sludge. Based on an analysis of the electric field distribution, a spiral reactor was designed and a continuous microwave system was built to conduct intermittent and continuous experiments under different conditions. Settling Volume, Capillary Suction Time, particle size, and moisture content of the sludge were measured. The results show that sludge pretreatment in continuous experiments has equally remarkable dehydration performance as in intermittent experiments; the minimum moisture content was 77.29% in the intermittent experiment under a microwave power of 300 W and an exposure time of 60 sec, and that in the continuous experiment was 77.56% under a microwave power of 400 W and an exposure time of 60 sec.The peak measured by Differential Scanning Calorimeter appeared earliest under a microwave power of 600 W and an exposure time of 180 sec. The heat flux at the peak was 4.343 W/g, which is relatively small. This indicates that microwave pretreatment induced desirable effects. The maximum yield of hydrogen production was 7.967% under the conditions of microwave power of 500 W, exposure time of 120 sec, and water bath at 55°C. This research provides a theoretical and experimental basis for the development of a continuous microwave sludge-conditioning system.Cuihong Zhou Xintong Huang Meng Zeng 2018Journal of Environmental Sciences2018,30,5:4
6Oxygen vacancy enhanced biomimetic superoxide dismutase activity of CeO_(2)-Gd nanozymes显示文摘Cerium oxide-based nanozymes have recently drawn much attention in the field of biomedical and antioxidant applications,because of their unique regenerative or autocatalytic properties.Herein,we studied the biomimetic superoxide dismutase(SOD)nanozymes CeO_(2)-Gd that combines the fluorescence properties of rare earth Gd with the antioxidant properties of CeO_(2)nanoparticles,which was prepared via facile route.The structure and composition of the CeO_(2)-Gd were measured and verified by X-ray powder diffraction(XRD),Raman spectroscopy,transmission electron microscopy(TEM),energydispersive X-ray spectroscopy(EDX),and X-ray electron spectroscopy(XPS).Confocal microscopy was used to image cells.Antioxidant performance and cell viability of these nanozymes were measured in vitro using BGC-803 cell.CeO_(2)-Gd nanozymes with a higher Ce^(3+)/Ce^(4+)ratio show higher superoxide dismutase(SOD)mimetic activity.Their antioxidant activity and fluorescence properties of CeO_(2)-Gd in BGC-803 cancer cells are enhanced by oxygen vacancies generated by doping rare-earth elements Gd.This work may guide the future design of CeO_(2)-Gd-based biomimetic nanozymes for anticancer and antioxidant applications.Xiangcheng Shi Jingjie Yang Xintong Wen Fuii Tian Changyan Li 2021Journal of Rare Earths2021,39,9:4
7Plasma-electrochemical synthesis of europium doped cerium oxide nanoparticles显示文摘In the present study,a plasma-electrochemical method was demonstrated for the synthesis of europium doped ceria nanoparticles.Ce(NO3)3· 6H2O and Eu(NO3)3·5H2O were used as the starting materials and being dissolved in the distilled water as the electrolyte solution.The plasma-liquid interaction process was in-situ investigated by an optical emission spectroscopy,and the obtained products were characterized by complementary analytical methods.Results showed that crystalline cubic CeO2:Eu3+ nanoparticles were successfully obtained,with a particle size in the range from 30 to 60 nm.The crystal structure didn't change during the calcination at a temperature from 400℃ to 1000℃,with the average erystallite size being estimated to be 52 nm at 1000℃.Eu3+ ions were shown to be effectively and uniformly doped into the CeO2 lattices.As a result,the obtained nanophosphors emit apparent red color under the UV irradiation,which can be easily observed by naked eye.The photoluminescence spectrum further proves the downshift behavior of the obtained products,where characteristic 5Do → 7F1,2,3 transitions of Eu3+ ions had been detected.Due to the simple,flexible and environmental friendly process,this plasma-electrochemical method should have great potential for the synthesis of a series of nanophosphors,especially for bio-application purpose.Liangliang Lin Xintong Ma Sirui Li Marly Wouters Volker Hessel 2019Frontiers of Chemical Science and Engineering2019,13,3:3
8Reservoir characteristics and well-logging evaluation of the Lower Cambrian shales in southeast Chongqing, China显示文摘To accurately identify the reservoir characteristics and main controlling factors of the Cambrian Niutitang black shale in the southeast Chongqing,a series of systematic measurements were conducted on core samples from Well Yuke-1 and Well Youke-1.The measurements include clay mineral analysis,XRD analysis,petrophysical properties,specific surface area,pore diameter and TOC,as well as R_(o) and maceral compositions.The Niutitang shale reservoir contains detrital minerals and clay minerals averagely of 51.34%and 32.74%,respectively.The average effective porosity and permeability are 1.2%and 8.0×10^(-3)mD,respectively,typically of ultra-low porosity and permeability.Mesopores are dominant,accounting for approximately 73%of the total pore volume.The average BET specific surface area is 7.75m^(2)/g and the average pore diameter is 5.3nm.The average TOC is 2.29%and the average R_(o) is 3.12%,indicating that the organic matter is in over-maturity stage.Statistical analyses of the measurements show that the micropore volume is positively correlated with TOC but negatively correlated with the total content of clay minerals;the mesopore volume is positively correlated with TOC,the total content of clay minerals and the con­tent of carbonate minerals;the macropore volume is positively correlated with TOC and the con­tent of carbonate minerals,weakly positively correlated with the content of detrital minerals but negatively correlated with the total content of clay minerals.The porosity and TOC of the Niuti­tang shale are computed using the conventional well-logging method for the Yuke-1 and Youke-1 wells,and the porosities are quite consistent with the core analysis resultsr,but in the shallow res­ervoir that contains no oil and gas,the TOC exhibits no correlation with the core analysis results.Xiaomeng Cao Bingsong Yu Xintong Li Mengdi Sun Ling Zhang 2016Petroleum Research2016,1,2:3
9Modeling of microstructure evolution of AZ80 magnesium alloy during hot working process using a unified internal state variable method显示文摘In this paper, a unified internal state variable(ISV) model for predicting microstructure evolution during hot working process of AZ80 magnesium alloy was developed. A novel aspect of the proposed model is that the interactive effects of material hardening, recovery and dynamic recrystallization(DRX) on the characteristic deformation behavior were considered by incorporating the evolution laws of viscoplastic flow, dislocation activities, DRX nucleation and boundary migration in a coupled manner. The model parameters were calibrated based on the experimental data analysis and genetic algorithm(GA) based objective optimization. The predicted flow stress, DRX fraction and average grain size match well with experimental results. The proposed model was embedded in the finite element(FE) software DEFORM-3 D via user defined subroutine to simulate the hot compression and equal channel angular extrusion(ECAE) processes. The heterogeneous microstructure distributions at different deformation zones and the dislocation density evolution with competitive deformation mechanisms were captured.This study can provide a theoretical solution for the hot working problems of magnesium alloy.Zexing Su Chaoyang Sun Mingjia Wang Lingyun Qian Xintong Li 2022Journal of Magnesium and Alloys2022,10,1:3
10Relationship between the parent charge transfer gap and maximum transition temperature in cuprates显示文摘One of the biggest puzzles concerning the cuprate high temperature superconductors is what determines the maximum transition temperature(Tc,max), which varies from less than 30 to above 130 K in different compounds.Despite this dramatic variation, a robust trend is that within each family, the double-layer compound always has higher Tc,maxthan the single-layer counterpart. Here we use scanning tunneling microscopy to investigate the electronic structure of four cuprate parent compounds belonging to two different families. We find that within each family, the double layer compound has a much smaller charge transfer gap size(DCT), indicating a clear anticorrelation between DCTand Tc,max. These results suggest that the charge transfer gap plays a key role in the superconducting physics of cuprates, which shed important new light on the high Tc mechanism from doped Mott insulator perspective.Wei Ruan Cheng Hu Jianfa Zhao Peng Cai Yingying Peng Cun Ye Runze Yu Xintong Li Zhenqi Hao Changqing Jin Xingjiang Zhou Zheng-Yu Weng Yayu Wang 2016Science Bulletin2016,61,23:3
11RAVL1 Activates IDD3 to Negatively Regulate Rice Resistance to Sheath Blight Disease显示文摘Sheath blight disease (ShB) has a severe impact on the production of rice. ABI3/VP1-like 1(RAVL1) negatively regulated the rice defense mechanism against ShB, however, this regulatorymechanism is not clearly understood. In this study, we identified that indeterminate domain 3 (IDD3) waspositively regulated by RAVL1. Further, chromatin immunoprecipitation (ChIP) assay, yeast one-hybridassay and transient expression assay indicated a direct binding between RAVL1 and the IDD3 promoterregion. IDD3 was ubiquitously expressed in different tissues and at different stages, and its expressionwas significantly enhanced by Rhizoctonia solani infection. IDD3 exhibited transcription activation activityin yeast and IDD3-GFP was found to be localized in the nucleus. IDD3 mutants exhibited no significantdifferences in response to ShB, while IDD3 overexpressors were more susceptible to ShB compared withwild type (WT) plants. Furthermore, IDD3 repressors were less susceptible to R. solani than WT plants.Interestingly, the expression of brassinosteroid-related genes (D2, D11 and BRI1) was lower in IDD3repressors and higher in IDD3 overexpressors compared with WT. However, the ChIP assay revealedthat IDD3 did not directly bind to the D2 and D11 promoters. Overexpression of IDD3 in BRI1 mutantd61-1 inhibited the activity of IDD3, reducing its susceptibility to ShB compared with IDD3 overexpressorand WT plants, indicating that IDD3 negatively regulated the rice defense mechanism against ShB by activatingthe BR signaling pathway. Thus, our analyses provided information to enhance the understanding of therice defense mechanism against ShB.SUN Qian YANG Shuo GUO Xiaofan WANG Siting JIA Xintong LI Shuang XUAN Yuanhu 2021Rice science2021,28,2:2
12Study on Phosphating by Ultrasonic Wave at Room Temperature for Sintered NdFeB Magnet显示文摘The corrosion behavior of a NdFeB magnet obtained at room temperature,with and without ultrasonic were investigated.The corrosion resistance was investigated by corrosion immersion tests in 3 wt%neutral NaCl solutions,potentiodynamic polarization tests and electrochemical impedance spectroscopy(EIS).The morphology of the conversion coatings on NdFeB surface were analyzed by scanning electron microscopy(SEM).And the forming mechanism of coatings was studied by potential-time curves.The tests of corrosion resistances show that the combination of phosphating treatment with ultrasonic will further improve the corrosion resistance of the NdFeB.The SEM also confirms that phosphating coating under ultrasonic is more homogeneous and compact.Sun Shuo Zhang Youping Yu Xintong Wang Yong Lou Guiyan 2012稀有金属材料与工程2012,41,S1:2
13Facile Synthesis of FePS3 Nanosheets@MXene Composite as a High-Performance Anode Material for Sodium Storage显示文摘Searching for advanced anode materials with excellent electrochemical properties in sodium-ion battery is essential and imperative for next-generation energy storage system to solve the energy shortage problem.In this work,two-dimensional(2D)ultrathin FePS3 nanosheets,a typical ternary metal phosphosulfide,are first prepared by ultrasonic exfoliation.The novel 2D/2D heterojunction of FePS3 nanosheets@MXene composite is then successfully synthesized by in situ mixing ultrathin MXene nanosheets with FePS3 nanosheets.The resultant FePS3 nanosheets@MXene hybrids can increase the electronic conductivity and specific surface area,assuring excellent surface and interfacial charge transfer abilities.Furthermore,the unique heterojunction endows FePS3 nanosheets@MXene composite to promote the diffusion of Na^+ and alleviate the drastic change in volume in the cyclic process,enhancing the sodium storage capability.Consequently,the few-layered FePS3 nanosheets uniformly coated by ultrathin MXene provide an exceptional reversible capacity of 676.1 mAh g^−1 at the current of 100 mA g^−1 after 90 cycles,which is equivalent to around 90.6% of the second-cycle capacity(746.4 mAh g^−1).This work provides an original protocol for constructing 2D/2D material and demonstrates the FePS3@MXene composite as a potential anode material with excellent property for sodium-ion batteries.Yonghao Ding Yu Chen Na Xu Xintong Lian Linlin Li Yuxiang Hu Shengjie Peng 2020Nano-Micro Letters2020,12,4:2
14Discovery and identification of EIF2AK2 as a direct key target of berberine for anti-inflammatory effects显示文摘Using chemoproteomic techniques,we first identified EIF2AK2,eEF1A1,PRDX3 and VPS4B as direct targets of berberine(BBR)for its synergistically anti-inflammatory effects.Of them,BBR has the strongest affinity with EIF2AK2 via two ionic bonds,and regulates several key inflammatory pathways through EIF2AK2,indicating the dominant role of EIF2AK2.Also,BBR could subtly inhibit the dimerization of EIF2AK2,rather than its enzyme activity,to selectively modulate its downstream pathways including JNK,NF-κB,AKT and NLRP3,with an advantage of good safety profile.In EIF2AK2 gene knockdown mice,the inhibitory IL-1β,IL-6,IL-18 and TNF-a secretion of BBR was obviously attenuated,confirming an EIF2AK2-dependent anti-inflammatory efficacy.The results highlight the BBR's network mechanism on anti-inflammatory effects in which EIF2AK2 is a key target,and inhibition of EIF2AK2 dimerization has a potential to be a therapeutic strategy against inflammationrelated disorders.Wei Wei Qingxuan Zeng Yan Wang Xixi Guo Tianyun Fan Yinghong Li Hongbin Deng Liping Zhao Xintong Zhang Yonghua Liu Yulong Shi Jingyang Zhu Xican Ma Yanxiang Wang Jiandong Jiang Danqing Song 2023Acta Pharmaceutica Sinica B2023,13,5:2
15Nontoxic engineered virus nanofibers as an efficient agent for the prevention and detection of fungal infection显示文摘Candida albicans (C。albicans ) 感染让高死亡在 immunocompromised 病人评价。由于当前的诊断系统的无效和对 candidiasis 的准许的疫苗的缺席, C 的预防。albicans 感染仍然是挑战。C。albicans 感染能被藏匿反的 aspartyl 朊酶评估并且阻止 2 抗体(anti-Sap2 IgG ) 和 Hsp90 抗体(anti-Hsp90 IgG ) 。在这研究,为诊断和 C 的预防的改进探索一个新代理人。albicans 感染,设计 fd 抗菌素,被认为对人安全的病毒 nanofiber,与二被设计并且准备能导致并且捕获 anti-Sap2 IgG 和 anti-Hsp90 IgG 的 epitopes。双显示的噬菌体作为一根新奇俘获探针被采用开发一个新连接酶的 immunosorbent 试金( ELISA )方法,它显著地 recombinant 蛋白质 Sap2 在被用作涂层抗原捕获特定的抗体( rSap2-ELISA )的 ELISA 和 recombinant 蛋白质 Hsp90 在被用作涂层抗原捕获特定的抗体( rHsp90-ELISA )的 ELISA 与那些相比改进了察觉率。另外, nanofibers 充当了一支潜在的疫苗使老鼠,以及 recombinant 蛋白质免疫,更高效地调停了体液、细胞的有免疫力的回答, C 的减少的层次。albicans 殖民,并且在 C 增加了幸存率。感染 albicans 的老鼠。因此,双显示的 nanofiber 被显示了是为保护对的一个强大的 bifunctional 代理人的噬菌体和临床的感染的敏感察觉,它有潜力广泛地在生命科学,临床的药,和环境科学被过去常。Yicun Wang Hongxi Shi Shuai Dong Yan Li Meng Wang Yanyan Huai Xintong Zhang Xi Chen Chuanbin Mao Xiang Gao Li Wang 2018Nano Research2018,11,4:2
16Zeolite templated carbon nanodots for broadband ultrafast pulsed fiber laser generation显示文摘Carbon nanodots(C-dots) with a uniform size of about 2 nm are synthesized via in situ pyrolysis of n-propylamine that is confined in the nanochannels of zeolite Linde Type A(LTA). The as-synthesized C-dots@LTA composite shows nonlinear optical saturable absorption properties in a broad wavelength band and can be used as saturable absorber(SA) to generate ultrafast pulsed fiber lasers. By inserting a zeolite LTA single crystal hosting C-dots into the fiber laser cavity, mode-locked fiber lasers with long-term operation stability at 1.5 μm and 1 μm are achieved. These results show that the C-dots@LTA are a promising SA material for ultrafast pulsed fiber laser generation in a broad wavelength band. To the best of our knowledge, this is the first demonstration of a C-dots@LTA-based mode-locked fiber laser.XINTONG XU JIAQI CHEN WENTAO SHI DALIN SUN SHAOWEN CHU LANG SUN WENFEI ZHANG YANPING CHEN JIANPANG ZHAI SHUANGCHEN RUAN ZIKANG TANG 2019Photonics Research2019,7,10:2
17Photocatalytic HER Performance of TiO_(2)-supported Single Atom Catalyst Based on Electronic Regulation:A DFT Study显示文摘Hydrogen is a kind of sustainable clean energy.Sunlight-driven hydrogen evolution reaction(HER)from water splitting assisted by photocatalysts is very crucial for developing clean energy technologies.Single-atom catalysts,such as atomically dispersed Pt on anatase(Pt1/TiO_(2))have exhibited excellent photocatalytic HER performance.However,the role of a single atom is still elusive.The mechanism of photocatalytic HER of TiO_(2)-supported noble metal single-atom catalysts has been studied.The supported single-atom Pt could narrow the bandgap of TiO_(2),enhance the optical absorption properties,and promote the transfer of the excited electrons.Excited electrons do not participate in the process of O-H cleavage,but can participate in the process of proton reduction and greatly reduce the hydrogen evolution energy barrier.Therefore,the hydrogen evolution energy can be used as a descriptor to evaluate the activity of TiO_(2)-supported single-atom catalysts.The activity of hydrogen evolution is found to be related to the number of d-band electrons of the single noble atom on M1/TiO_(2)(M=Pd,Pt,Rh,Ir).The increase of the number of d electrons in the single atom could reduce the hydrogen evolution energy and promote the hydrogen evolution process.SONG Weiyu LV Xintong GAO Yang WANG Lu 2022Chemical Research in Chinese Universities2022,38,4:2
18TiO2 photoeatalysis and related surface phenomena 显示文摘Fujishima Akira Zhang Xintong Tryk D A 2008Surfave Science Reports2008,63,12:1
19Titanium dioxide photocatalysis:present situation and future appro- aches显示文摘FUJISHIM Akira ZHANG Xintong 2005Comptes Rendus Chimie2005,9,5:1
20TiO2 Photocatalysis and related surface phenomena显示文摘Fujishima Akira Zhang Xintong Donald A Tryk 0,,12:1
返回顶部 每页显示:
共9页 首页 上一页 第1页 下一页 末页 /9 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费