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| 1 | Research on Key Technologies of Precise InSAR Surveying and Mapping Applications Using Automatic SAR Imaging显示文摘Precise interferometric synthetic aperture radar (InSAR) is a new intelligent photogrammetric technology that uses automatic imaging and processing means. Precise InSAR has become the most efficient satellite surveying and mapping (SASM) method that uses the interferometric phase to create a global digital elevation model (DEM) with high precision. In this paper, we propose the application of systematic InSAR technologies to SASM. Three key technologies are proposed: calibration technology, data processing technology and post-processing technology. First, we need to calibrate the geometric and interferometric parameters including the azimuth time delay, range time delay, and atmospheric delay, as well as baseline errors. Second, we use the calibrated parameters to create a precise DEM. One of the important procedures in data processing is the determination of phase ambiguities. Finally, we improve the DEM quality through the joint use of the block adjustment method, long and short baseline combination method and descending and ascending data merge method. We use 6 sets of TanDEM-X data covering Shanxi to conduct the experiment. The root mean square error of the final DEM is 5.07 m in the mountainous regions. In addition, the low coherence area is 0.8 km 2. The result meets the China domestic SASM accuracy standard at both the 1∶50 000 and 1∶25 000 measurement scales. | Xinming TANG Tao LI Xiaoming GAO Qianfu CHEN Xiang ZHANG | 2019 | Journal of Geodesy and Geoinformation Science2019,2,2: | 20 |
| 2 | Changes in visibility with PM_(2.5) composition and relative humidity at a background site in the Pearl River Delta region显示文摘In fall–winter, 2007–2013, visibility and light scattering coefficients(b sp) were measured along with PM_(2.5)mass concentrations and chemical compositions at a background site in the Pearl River Delta(PRD) region. The daily average visibility increased significantly(p < 0.01) at a rate of 1.1 km/year, yet its median stabilized at ~13 km. No haze days occurred when the 24-hr mean PM_(2.5)mass concentration was below 75 μg/m^3. By multiple linear regression on the chemical budget of particle scattering coefficient(b sp), we obtained site-specific mass scattering efficiency(MSE) values of 6.5 ± 0.2, 2.6 ± 0.3, 2.4 ± 0.7 and 7.3 ± 1.2 m2/g,respectively, for organic matter(OM), ammonium sulfate(AS), ammonium nitrate(AN) and sea salt(SS). The reconstructed light extinction coefficient(b ext) based on the Interagency Monitoring of Protected Visual Environments(IMPROVE) algorithm with our site-specific MSE revealed that OM, AS, AN, SS and light-absorbing carbon(LAC) on average contributed 45.9% ± 1.6%,25.6% ± 1.2%, 12.0% ± 0.7%, 11.2% ± 0.9% and 5.4% ± 0.3% to light extinction, respectively.Averaged b ext displayed a significant reduction rate of 14.1/Mm·year(p < 0.05); this rate would be 82% higher if it were not counteracted by increasing relative humidity(RH) and hygroscopic growth factor(f(RH)) at rates of 2.5% and 0.16/year-1(p < 0.01), respectively, during the fall–winter, 2007–2013. This growth of RH and f(RH) partly offsets the positive effects of lowered AS in improving visibility, and aggravated the negative effects of increasing AN to impair visibility. | Xiaoxin Fu Xinming Wang Qihou Hu Guanghui Li Xiang Ding Yanli Zhang Quanfu He Tengyu Liu Zhou Zhang Qingqing Yu Ruqing Shen Xinhui Bi | 2016 | Journal of Environmental Sciences2016,28,2: | 18 |
| 3 | Effect of pre-deformation on the stress corrosion cracking susceptibility of aluminum alloy 2519显示文摘The effects of pre-deformation and strain rate on the stress corrosion cracking (SCC) behavior of aluminum alloy 2519 in air and in 3.5% NaCl water solution were investigated by means of slow strain rate tension (SSRT), scanning elec- tron microscopy (SEM), and transmission electron microscopy (TEM). The results indicate that the alloy is susceptible to SCC in 3.5% NaCl water solution and not in air. At the same pre-deformation, the alloy is more susceptible to SCC at 1.33 × 10·5 s·1 than at 6.66 × 10·5 s·1. Moreover, it is more susceptible to SCC at free pre-deformation than at 10% pre-deformation at the same strain rate. The number of θ precipitated along the grain boundaries is reduced and distributed discontinuously, at the same time, the precipitate-free zones (PFZ) become narrow and the susceptibility to stress corrosion cracking is reduced after 10% pre-deformation. | LI Huizhong ZHANG Xinming CHEN Mingan LI Yanfang LIANG Xiaopeng | 2007 | Rare Metals2007,26,4: | 15 |
| 4 | TALEN-based generation of a cynomolgus monkey disease model for human microcephaly显示文摘基因在非人类的首领编辑可以为在人探索病原学和遗传上基于的神经病学的混乱的治疗学的策略导致珍贵模型。然而,仔细在人模仿病理学、行为的赤字的神经病学的混乱的一个猴子模型成功地还没被产生了。Microcephalin 1 (MCPH1 ) 在人的大脑,和智力迟钝伴随的 MCPH1 变化原因头小畸型的进化被含有。这里,我们产生了用抄写带 biallelic MCPH1 变化的一只 cynomolgus 猴子(Macaca fascicularis ) 像使活跃之物的受动器核酸酶。猴子概括了大多数在病人观察的重要临床的特征,包括在头圆周,早熟的染色体冷凝作用(PCC ) ,语料库 callosum 的发育不全和上面的手足 spasticity 的显著减小。而且,在变异的真皮的成纤维细胞的 MCPH1 的 overexpression 救了 PCC 症候群。这个猴子模型可以帮助我们阐明在人的头小畸型并且更好的致病的 MCPH1 的角色在首领大脑尺寸的进化理解这蛋白质的功能。 | Qiong Ke Weiqiang Li Xingqiang Lai Hong Chen Lihua Huang Zhuang Kang Kai Li Jie Ren Xiaofeng Lin Haiqing Zheng Weijun Huang Yunhan Ma Dongdong Xu Zheng Chen Xinming Song Xinyi Lin Min Zhuang Tao Wang Fengfeng Zhuang Jianzhong Xi Frank Fuxiang Mao Huimin Xia Bruce T Lahn Qi Zhou Shihua Yang Andy Peng Xiang | 2016 | Cell Research2016,26,9: | 13 |
| 5 | Soil Components Affecting Phosphate Sorption Parameters of Acid Paddy Soils in Guangdong Province显示文摘Soil components affecting phosphate sorption parameters were studied using acid paddy soils derived from basalt, granite, sand-shale and the Pearl River Delta sediments, respectively, in Guangdong Province. For each soil, seven 2.50 g subsamples were equilibrated with 50 mL 0.02 mol L-1 (pH=7.0) of KCI containing 0, 5, 10, 15, 25, 50 and 100 mg P kg-1, respectively, in order to derive P sorption parameters (P sorption maximum, P sorption intensity factor and maximum buffer capacity) by Langmuir isotherm equation. It was shown that the main soil components influencing phosphate sorption maximum (Xm) included soil clay, PH, amorphous iron oxide (Feo) and amorphous aluminum oxide (Alo), with their effects in the order of Alo > Feo > pH > clay. Among these components, pH had a negative effect, and the others had a positive effect. Organic matter (OM) was the only soil component influencing P sorption intensity factor (K). The main components influencing maximum phosphate buffer capacity (MBC) consisted of soil clay, OM,pH, Feo and Alo, with their effects in the order of Alo > OM > pH > Feo > clay. Path analysis indicated that among the components with positive effects on maximum phosphate buffer capacity (MBC), the effect was in the order of Alo > Feo > Clay, while among the components with negative effects, OM > pH. OM played an important role in mobilizing phosphate in acid paddy soils mainly through decreasing the sorption immensity of phosphate by soil particles. | LI HUAXING, ZHANG XINMING and LIU YUANJIN (College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642 China) | 2000 | Pedosphere2000,10,4: | 13 |
| 6 | Parameter identification of hysteretic model of rubber-bearing based on sequential nonlinear least-square estimation显示文摘In order to evaluate the nonlinear performance and the possible damage to rubber-bearings (RBs) during their normal operation or under strong earthquakes, a simplified Bouc-Wen model is used to describe the nonlinear hysteretic behavior of RBs in this paper, which has the advantages of being smooth-varying and physically motivated.Further, based on the results from experimental tests performed by using a particular type of RB (GZN110) under different excitation scenarios, including white noise and several earthquakes, a new system identification method, referred to as the sequential nonlinear least-square estimation (SNLSE), is introduced to identify the model parameters.It is shown that the proposed simplified Bouc-Wen model is capable of describing the nonlinear hysteretic behavior of RBs, and that the SNLSE approach is very effective in identifying the model parameters of RBs. | Yin Qiang Zhou Li Wang Xinming | 2010 | Earthquake Engineering and Engineering Vibration2010,9,3: | 9 |
| 7 | Effect of Exposure to Trace Elements in the Soil on the Prevalence of Neural Tube Defects in a High-Risk Area of China显示文摘Objective Our objective is to build a model that explains the association between the exposure to trace elements in the soil and the risk of neural tube defects. Methods We built a function with different parameters to describe the effects of trace elements on neural tube defects. The association between neural tube defects and trace element levels was transformed into an optimization problem using the maximum likelihood method. Results Tin, lead, nickel, iron, copper, and aluminum had typical layered effects (dosage effects) on the prevalence of neural tube defects. Arsenic, selenium, zinc, strontium, and vanadium had no effect, and molybdenum had one threshold value that affected the prevalence of birth defects. Conclusion As an exploratory research work, our model can be used to determine the direction of the effect of the trace element content of cultivated soil on the risk of neural tube defects, which shows the clues by the dosage effect of their toxicological characteristics. Based on our findings, future biogeochemical research should focus on the direct effects of trace elements on human health. | HUANG Jing WU JiLei LI TieJun SONG XinMing ZHANG BingZi ZHANG PingWen ZHENG XiaoYing | 2011 | Biomedical and Environmental Sciences2011,24,2: | 9 |
| 8 | Regenerative Braking Strategy for Motor Hoist by Ultracapacitor显示文摘Rising concern in environmental issues on global scale has made energy saving in powered equipment a very important subject.In order to improve the energy efficiency and driving range of a motor hoist,a regenerative braking system is designed and discussed.The system takes a unique ultracapacitor-only approach to energy storage system.The bi-directional bride DC?DC converter which regulates current flow to and from the ultracapacitor operates in two modes:boost and buck,depending on the direction of the flow.In order to provide constant input and output current at the ultracapacitor,this system uses a double proportional-integral(PI) control strategy in regulating the duty cycle of PWM to the DC?DC converter.The permanent magnet synchronous motor(PWSM) drive system is also studied.The space vector pulse width modulation(SVPWM) technique,along with a two-closed-loop vector control model,is adopted after detailed analysis of PMSM characteristics.The overall model and control strategy for this regenerative braking system is ultimately built and simulated under the MATLAB and Simulink environment.A test platform is built to obtain experimental results.Analysis of the results reveals that more than half of the gravitational potential energy can be recovered by this system.Simulation and experimentation results testify the validity of the double PI control strategy for interface circuit of ultracapacitor and SVPWM strategy for PMSM. | BIAN Yongming ZHU Lijing LAN Hao LI Anhu XU Xinming | 2012 | Chinese Journal of Mechanical Engineering2012,25,2: | 7 |
| 9 | Grease film evolution in rolling elastohydrodynamic lubrication contacts显示文摘Although most rolling element bearings are grease lubricated,the underlying mechanisms of grease lubrication has not been fully explored.This study investigates grease film evolution with glass disc revolutions in rolling elastohydrodynamic lubrication(EHL)contacts.The evolution patterns of the grease films were highly related to the speed ranges and grease structures.The transference of thickener lumps,film thickness decay induced by starvation,and residual layer were recognized.The formation of an equilibrium film determined by the balance of lubricant loss and replenishment was analyzed.The primary mechanisms that dominate grease film formation in different lubricated contacts were clarified. | Xinming LI Feng GUO Gerhard POLL Yang FEI Ping YANG | 2021 | Friction2021,9,1: | 7 |
| 10 | Atorvastatin protects cardiac progenitor cells from hypoxia-induced cell growth inhibition via MEG3/miR-22/HMGB1 pathway显示文摘Heart failure (HF)induced by ischemia myocardial infarction (MI)is one of the major causes of morbidity and mortality all around the world.Atorvastatin,a hydroxyrnethylglutaryl coenzyme A reductase inhibitor,has been demonstrated to benefit patients with ischemic or non-ischemicinduced HF,but the mechanism is still poorly understood.Increasing evidence indicates that IncRNAs play important role in variety of human disease.However,the role and underlying molecular mechanisms remain largely unclear.In our work,we applied 0.5%02 to generate a hypoxia cardiac progenitor cell (CPC)model.Then,CCK8 and EdU assays were employed to investigate the role of atorvastatin in hypoxia CPC cell model.We found that hypoxia inhibits CPC viability and proliferation through modulating MEG3 expression,while atorvastatin application can protect CPCs from hypoxia-induced injury through inhibiting MEG3 expression.Then,we demonstrated that repression of MEG3 inhibited the hypoxia-induced injury of CPCs and overexpression of MEG3 inhibited the protective effect of atorvastatin in the hypoxia-induced injury of CPCs.Furthermore,our study illustrated that atorvastatin played its role in CPC viability and proliferation by modulating the expression of HMGB1 through the MEG3/miR-22 pathway.Our study, for the first time,uncovered the molecular mechanism of atorvastatin's protective role in cardiomyocytes under hypoxia condition,which may provide an exploitable target in developing effective therapy drugs for MI patients. | Jinwen Su Ming Fang Bei Tian Jun Luo Can Jin Xuejun Wang Zhongping Ning Xinming Li | 2018 | Acta Biochimica et Biophysica Sinica2018,50,12: | 6 |
| 11 | Rush-hour aromatic and chlorinated hydrocarbons in selected subway stations of Shanghai,China显示文摘Air samples were collected simultaneously at platform,mezzanine and outdoor in five typical stations of subway system in Shanghai,China using stainless steel canisters and analyzed by gas chromatography-mass selective detector (GC-MSD) after cryogenic pre-concentration.Benzene,toluene,ethylbenzene and xylenes (BTEX) at the platforms and mezzanines inside the stations averaged (10.3±2.1),(38.7±9.0),(19.4±10.1) and (30.0±11.1) μg/m 3,respectively;while trichloroethylene (TrCE),tetrachloroethylene (TeCE) and para-dichlorobenzene (pDCB),vinyl chloride and carbon tetrachloride were the most abundant chlorinated hydrocarbons inside the stations with average levels of (3.6±1.3),(1.3±0.5),(4.1±1.1),(2.2±1.1) and (1.2±0.3) μg/m 3,respectively.Mean levels of major aromatic and chlorinated hydrocarbons were higher indoor (platforms and mezzanines) than outdoor with average indoor/outdoor (I/O) ratios of 1.1-9.5,whereas no significant indoor/outdoor differences were found except for benzene and TrCE.The highly significant mutual correlations (p<0.01) for BTEX between indoor and outdoor and their significant correlation (p<0.05) with methyl tert-butyl ether (MTBE),a marker of traffic-related emission without other indoor and outdoor sources,indicated that BTEX were introduced into the subway stations from indoor/outdoor air exchange and traffic emission should be their dominant source.TrCE and pDCB were mainly from indoor emission and TeCE might have both indoor emission sources and contribution from outdoor air,especially in the mezzanines. | Yanli Zhang Chunlei Li Xinming Wang Hai Guo Yanli Feng Jianmin Chen | 2012 | Journal of Environmental Sciences2012,24,1: | 6 |
| 12 | Influence of Mg Contents on Aging Precipitation Behavior of Al-3.5Cu-xMg Alloy显示文摘The influence of Mg content on the microstructures and mechanical properties at room temperatures of Al-3.5Cu-(0.71-1.81)Mg alloys was studied.Precipitation phases in the alloys were identified by TEM and HRTEM.The results show that when Mg contents increase from 0.71 to 1.81 wt%,the precipitates are transformed from S,S″,Ω,and θ' phases to Sand S′phases,and Ω phase is first observed in Al-3.48Cu-0.71 Mg alloy with Cu/Mg mass ratio of 5 during the conventional aging heat treatment(190 ℃/12 h).Regard to aging hardness effect of the tested alloys,the hardness of the alloys improves with the increase of Mg content,but the increases become slow when Mg content is greater than 1.35 wt%. | Siyu Li Jin Zhang Jinlong Yang Yunlai Deng Xinming Zhang | 2014 | Acta Metallurgica Sinica(English Letters)2014,27,1: | 6 |
| 13 | Collaborative Network Security in Multi-Tenant Data Center for Cloud Computing显示文摘A data center is an infrastructure that supports Internet service. Cloud computing is rapidly changing the face of the Internet service infrastructure, enabling even small organizations to quickly build Web and mobile applications for millions of users by taking advantage of the scale and flexibility of shared physical infrastructures provided by cloud computing. In this scenario, multiple tenants save their data and applications in shared data centers, blurring the network boundaries between each tenant in the cloud. In addition, different tenants have different security requirements, while different security policies are necessary for different tenants. Network virtualization is used to meet a diverse set of tenant-specific requirements with the underlying physical network, enabling multi-tenant datacenters to automatically address a large and diverse set of tenants requirements. In this paper, we propose the system implementation of vCNSMS, a collaborative network security prototype system used in a multi-tenant data center. We demonstrate vCNSMS with a centralized collaborative scheme and deep packet inspection with an open source UTM system. A security level based protection policy is proposed for simplifying the security rule management for vCNSMS. Different security levels have different packet inspection schemes and are enforced with different security plugins. A smart packet verdict scheme is also integrated into vCNSMS for intelligence flow processing to protect from possible network attacks inside a data center network. | Zhen Chen Wenyu Dong Hang Li Peng Zhang Xinming Chen Junwei Cao | 2014 | Tsinghua Science and Technology2014,19,1: | 5 |
| 14 | Influence of Range Gate Width on Detection Probability and Ranging Accuracy of Single Photon Laser Altimetry Satellite显示文摘The influence of the single photon laser altimeter range-gate width on the detection probability and ranging accuracy is discussed and analyzed,according to the LiDAR equation,single photon detection equation and the Monte Carlo method to simulate the experiment.The simulated results show that the probability of detection is not affected by the range gate,while the probability of false alarm is relative to the gate width.When the gate width is 100 ns,the ranging accuracy can accord with the requirements of satellite laser altimeter.But when the range gate width exceeds 400 ns,ranging accuracy will decline sharply.The noise ratio will be more as long as the range gate to get larger,so the refined filtering algorithm during the data processing is important to extract the useful photons effectively.In order to ensure repeated observation of the same point for 25 times,we deduce the quantitative relation between the footprint size,footprint,and frequency repetition according to the parameters of ICESat-2.The related conclusions can provide some references for the design and the development of the domestic single photon laser altimetry satellite. | Guoyuan LI Fanghong YE Xinming TANG Dongping XIE Jiapeng HUANG Genhua HUANG | 2020 | Journal of Geodesy and Geoinformation Science2020,3,2: | 4 |
| 15 | Laser pattern-induced unidirectional lubricant flow for lubrication track replenishment显示文摘Effective oil replenishment to the lubrication track of a running bearing is crucial to its sustainable operation.Reliable practical solutions are rare despite numerous theoretical studies were conducted in the last few decades.This paper proposes the use of surface effect,wettability gradient,to achieve the goal.This method is simple and can be nicely implemented using femtosecond laser ablation.A periodic comb-tooth-shaped pattern with anisotropic wetting capability is devised and its effect on the anisotropic spreading behaviour of an oil droplet is studied.Results show that the comb-tooth-shaped pattern enables the rearrangement of oil distribution,thereby escalating oil replenishment to the lubrication track.The effect is due to the unbalanced interfacial force created by the surface pattern.The influence of the shape and the pitch of teeth,which are the two governing factors,on oil transport is also reported.The effects of the newly devised surface pattern on lubrication are experimentally evaluated under the conditions of limited lubricant supply.These results are promising,demonstrating the reduction in bearing friction and the increase in lubricating film thickness. | Chenglong LIU Feng GUO Patrick WONG Xinming LI | 2022 | Friction2022,10,8: | 4 |
| 16 | Atom table convolutional neural networks for an accurate prediction of compounds properties显示文摘Machine learning techniques are widely used in materials science.However,most of the machine learning models require a lot of prior knowledge to manually construct feature vectors.Here,we develop an atom table convolutional neural networks that only requires the component information to directly learn the experimental properties from the features constructed by itself.For band gap and formation energy prediction,the accuracy of our model exceeds the standard DFT calculations.Besides,through dataenhanced technology,our model not only accurately predicts superconducting transition temperatures,but also distinguishes superconductors and non-superconductors.Utilizing the trained model,we have screened 20 compounds that are potential superconductors with high superconducting transition temperature from the existing database.In addition,from the learned features,we extract the properties of the elements and reproduce the chemical trends.This framework is valuable for high throughput screening and helpful to understand the underlying physics. | Shuming Zeng Yinchang Zhao Geng Li Ruirui Wang Xinming Wang Jun Ni | 2019 | npj Computational Materials2019,,1: | 4 |
| 17 | The dual-inhibitory effect of miR-338-5p on the multidrug resistance and cell growth of hepatocellular carcinoma显示文摘Chemotherapeutic treatments against hepatocellular carcinoma(HCC)are necessary for both inoperable patients to improve prospects for survival and surgery patients to improve the outcome after surgical resection.However,multidrug resistance(MDR)is a major obstacle to obtaining desirable results.Currently,increasing the chemotherapy sensitivity of tumor cells or discovering novel tumor inhibitors is an effective therapeutic strategy to solve this issue.In the present study,we uncovered the dual-inhibitory effect of miR-338-5p:on the one hand,it could downregulate ABCB1 expression and sensitize HCC cells to doxorubicin and vinblastine by directly targeting the 3′-untranslated region(3′-UTR)of ABCB1,while,on the other hand,it could suppress the proliferation of HCC cells by directly targeting the 3′-UTR of EGFR and reducing EGFR expression.Since EGFR regulates ABCB1 levels,the indirect action of miR-338-5p in ABCB1 modulation was revealed,in which miR-338-5p inhibits ABCB1 expression by targeting the EGFR/ERK1/2 signaling pathway.These data indicate that the miR-338-5p/EGFR/ABCB1 regulatory loop plays a critical role in HCC,and a negative correlation between miR-338-5p and EGFR or ABCB1 was also detected in HCC clinical samples.In conclusion,these findings reveal a critical role for miR-338-5p in the regulation of MDR and proliferation of HCC,suggesting the potential therapeutic implications of miR-338-5p in HCC treatment. | Yang Zhao Jing Chen Wenxin Wei Xinming Qi Chunzhu Li Jin Ren | 2018 | Signal Transduction and Targeted Therapy2018,3,1: | 4 |
| 18 | Fabrication of large area hexagonal boron nitride thin films for bendable capacitors显示文摘高度可靠、可弯曲的电介质为未来应用在灵活或可弯曲的电子设备被需要。六角形的硼氮化物(h-BN ) 能由于它的宽乐队差距被用作可弯曲的电介质。这里,我们由一个低压力化学药品蒸汽免职方法与可控制的厚度制作高质量的 h-BN 电影。我们作为电介质用 h-BN 电影表明一个平行板的电容器。h-BN 电容器与 9.0 MV/cm 的高故障地力量是可靠的。越过 h-BN 电影的通道电流对电介质的厚度相反地指数,它让电容显著地落下。h-BN 电容器显示出 6.8 F/cm2 的一个最好的特定的电容,它比计算的值高一个数量级。 | Ning Guo Jinquan Wei Yi Jia Huanhuan Sun Yuhang Wang Kehan Zhao Xiaolan Shi Liuwan Zhang Xinming Li Anyuan Cao Hongwei Zhu Kunlin Wang Dehai Wu | 2013 | Nano Research2013,6,8: | 3 |
| 19 | Secondary aerosol formation and oxidation capacity in photooxidation in the presence of Al_2O_3 seed particles and SO_2显示文摘To investigate the sensitivity of secondary aerosol formation and oxidation capacity to NOx in homogeneous and heterogeneous reactions, a series of irradiated toluene/NOx/air and ?-pinene/NOx/air experiments were conducted in smog chambers in the absence or presence of Al2O3 seed particles. Various concentrations of NOx and volatile organic compounds(VOCs) were designed to simulate secondary aerosol formation under different scenarios for NOx. Under 'VOC-limited' conditions, the increasing NOx concentration suppressed secondary aerosol formation, while the increasing toluene concentration not only contributed to the increase in secondary aerosol formation, but also led to the elevated oxidation degree for the organic aerosol. Sulfate formation was suppressed with the increasing NOx due to a decreased oxidation capacity of the photooxidation system. Secondary organic aerosol(SOA) formation also decreased with the presence of high concentration of NOx, because organo-peroxy radicals(RO2) react with NOx instead of with peroxy radicals(RO2 or HO2), resulting in the formation of volatile organic products. The increasing concentration of NOx enhanced the formation of sulfate, nitrate and SOA under 'NOx-limited' conditions, in which the heterogeneous reactions played an important role. In the presence of Al2O3 seed particles, a synergetic promoting effect of mineral dust and NOx on secondary aerosol formation in heterogeneous reactions was observed in the photooxidation. This synergetic effect strengthened the positive relationship between NOx and secondary aerosol formation under 'NOx-limited' conditions but weakened or even overturned the negative relationship between NOx and secondary aerosol formation under 'VOC-limited' conditions. Sensitivity of secondary aerosol formation to NOx seemed different in homogeneous and heterogeneous reactions, and should be both taken into account in the sensitivity study. The sensitivity of secondary aerosol formation to NOx was further investigated under 'winter-like' and NH3-rich conditions. No obvious difference for the sensitivity of secondary aerosol formation except nitrate to NOx was observed. | Biwu Chu Tengyu Liu Xiao Zhang Yongchun Liu Qingxin Ma Jinzhu Ma Hong He Xinming Wang Junhua Li Jiming Hao | 2015 | Science China Chemistry2015,58,9: | 3 |
| 20 | Development of two TaqMan real-time reverse transcription-PCR assays for the detection of severe acute respiratory syndrome coronavirus-2显示文摘The outbreak of coronavirus disease 2019(COVID-19)in Wuhan,China,was caused by a novel coronavirus(CoV),named severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).The rapid detection of viral nucleic acids is critical for the early identification of infected cases.We have developed two TaqMan real-time reverse transcription-PCR assays to detect SARS-CoV-2.The designed primers target the nucleocapsid(N)and open reading frame(ORF)1b gene regions,where the probes discriminate SARS-CoV-2 from other human and animal CoVs.The sensitivities are one genomic copy per reaction for theN gene assay and ten copies for the ORF 1b gene assay.The overall linear detection ranges are 1–10^(6)and 10–10^(6)copies per reaction for the N gene assay and the ORF 1b gene assay,respectively.Surveillance of 23 suspected COVID-19 patients demonstrated that SARS-CoV-2 could be detected from 100%(23/23)and 62.5%(16/23)of clinical specimens by the N gene assay and the ORF 1b gene assay,respectively.All of the samples not detected by the ORF 1b gene assay were throat swabs,indicating a lower viral load in the upper respiratory tract and the relatively lower sensitivity of the ORF 1b gene assay.The assays developed in the present study offer alternative diagnostic tests for COVID-19. | Yiwei Liu Yingying Wang Xinming Wang Yan Xiao Lan Chen Li Guo Jianguo Li Lili Ren Jianwei Wang | 2020 | Biosafety and Health2020,2,4: | 3 |