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| 1 | Enhanced secondary pollution offset reduction of primary emissions during COVID-19 lockdown in China显示文摘To control the spread of the 2019 novel coronavirus(COVID-19),China imposed nationwide restrictions on the movement of its population(lockdown)after the Chinese New Year of 2020,leading to large reductions in economic activities and associated emissions.Despite such large decreases in primary pollution,there were nonetheless several periods of heavy haze pollution in eastern China,raising questions about the well-established relationship between human activities and air quality.Here,using comprehensive measurements and modeling,we show that the haze during the COVID lockdown was driven by enhancements of secondary pollution.In particular,large decreases in NOx emissions from transportation increased ozone and nighttime NO_(3)radical formation,and these increases in atmospheric oxidizing capacity in turn facilitated the formation of secondary particulate matter.Our results,afforded by the tragic natural experiment of the COVID-19 pandemic,indicate that haze mitigation depends upon a coordinated and balanced strategy for controlling multiple pollutants. | Xin Huang Aijun Ding Jian Gao Bo Zheng Derong Zhou Ximeng Qi Rong Tang Jiaping Wang Chuanhua Ren Wei Nie Xuguang Chi Zheng Xu Liangduo Chen Yuanyuan Li Fei Che Nini Pang Haikun Wang Dan Tong Wei Qin Wei Cheng Weijing Liu Qingyan Fu Baoxian Liu Fahe Chai Steven JDavis Qiang Zhang Kebin He | 2021 | National Science Review2021,8,2: | 47 |
| 2 | Isolation and characterization of atrazine-degrading Arthrobacter sp. AD26 and use of this strain in bioremediation of contaminated soil显示文摘A bacterial strain (AD26) capable of utilizing atrazine as a sole nitrogen source for growth was isolated from an industrial wastewater sample by enrichment culture. The 16S rRNA gene sequencing identified AD26 as an Arthrobacter sp. PCR assays indicated that AD26 contained atrazine-degrading genes trzN and atzBC. The trzN gene of AD26 only differs from the trzN of Arthrobacter aurescens TC1 by one base (A→T at 907) and one amino acid (Met→Leu at 303). The specific activity of trzN of AD26 in crude cell extract was 0.28 U/mg, which was 1.2 times that of TC1. This strain has shown faster growth and atrazine-degradation rates in atrazine-containing minimal media than two well characterized atrazine-degrading bacteria, Pseudomonas sp. ADP and Arthrobacter aurescens TC1. After incubating for 48 h at 30°C, the OD600 of AD26 reached 2.6 compared with 1.33 of ADP. AD26 was capable of degrading 500 mg/L of atrazine in minimal medium at 95% in 72 h, while the degradative rates by TC1 and ADP were only 90% and 86%, respectively. A bioremediation trial of contaminated soil has indicated that AD26 can degrade as high as 98% of atrazine contained in soil (300 mg/kg) after incubating for 20 d at 26°C, nominating this strain as a good candidate for use in bioremediation programs. | Li Qingyan Li Ying Zhu Xikun Cai Baoli | 2008 | Journal of Environmental Sciences2008,20,10: | 18 |
| 3 | De novo mutation in ATP6V1B2 impairs lysosome acidification and causes dominant deafness-onychodystrophy syndrome显示文摘 | Yongyi Yuan Jianguo Zhang Qing Chang Jin Zeng Feng Xin Jianjun Wang Qingyan Zhu Jing Wu Jingqiao Lu Weiwei Guo Xukun Yan Hui Jiang Binfei Zhou Qi Li Xue Gao Huijun Yuan Shiming Yang Dongyi Han Zixu Mao Ping Chen Xi Lin Pu Dai | 2014 | Cell Research2014,24,11: | 13 |
| 4 | Ore Genesis of the Kalatongke Cu-Ni Sulfide Deposits, Western China: Constraints from Volatile Chemical and Carbon Isotopic Compositions显示文摘The Kalatongke Cu-Ni sulfide deposits located in the East Junggar terrane, northern Xinjiang, western China are the largest magmatic sulfide deposits in the Central Asian Orogenic Belt (CAOB). The chemical and carbon isotopic compositions of the volatiles trapped in olivine, pyroxene and sulfide mineral separates were analyzed by vacuum stepwise-heating mass spectrometry. The results show that the released volatiles are concentrated at three temperature intervals of 200-400°C, 400-900°C and 900-1200°C. The released volatiles from silicate mineral separates at 400-900°C and 900-1200°C have similar chemical and carbon isotopic compositions, which are mainly composed of H2O (av. ~92 mol%) with minor H2, CO2, H2S and SO2, and they are likely associated with the ore-forming magmatic volatiles. Light δ13CCO2 values (from -20.86‰ to -12.85‰) of pyroxene indicate crustal contamination occurred prior to or synchronous with pyroxene crystallization of mantlederived ore-forming magma. The elevated contents of H2 and H2O in the olivine and pyroxene suggest a deep mantle-originated ore-forming volatile mixed with aqueous volatiles from recycled subducted slab. High contents of CO2 in the ore-forming magma volatiles led to an increase in oxygen fugacity, and thereby reduced the solubility of sulfur in the magma, then triggered sulfur saturation followed by sulfide melt segregation; CO2 contents correlated with Cu contents in the whole rocks suggest that a supercritical state of CO2 in the ore-forming magma system under high temperature and pressure conditions might play a key role in the assemblage of huge Cu and Ni elements. The volatiles released from constituent minerals of intrusion 1# have more CO2 and SO2 oxidized gases, higher CO2/CH4 and SO2/H2S ratios and lighter δ13CCO2 than those of intrusions 2# and 3#. This combination suggests that the higher oxidation state of the volatiles in intrusion 1# than intrusions 2# and 3#, which could be one of key ore-forming factors for large amounts of ores and high contents of Cu and Ni in intrusion 1#. The volatiles released at 200-400°C are dominated by H2O with minor CO2, N2+CO and SO2, with δ13CCO2 values (-25.66‰ to -22.98‰) within the crustal ranges, and are considered to be related to secondary tectonic-hydrothermal activities. | FU Piaoer TANG Qingyan ZHANG Mmgjie ZHANG Zhaowei LI Liwu LI Wenyuan | 2012 | Acta Geologica Sinica(English Edition)2012,86,3: | 11 |
| 5 | Classification of hyperspectral remote sensing images using frequency spectrum similarity显示文摘An algorithm of hyperspectral remote sensing images classification is proposed based on the frequency spectrum of spectral signature.The spectral signature of each pixel in the hyperspectral image is taken as a discrete signal,and the frequency spectrum is obtained using discrete Fourier transform.The discrepancy of frequency spectrum between ground objects' spectral signatures is visible,thus the difference between frequency spectra of reference and target spectral signature is used to measure the spectral similarity.Canberra distance is introduced to increase the contribution from higher frequency components.Then,the number of harmonics involved in the proposed algorithm is determined after analyzing the frequency spectrum energy cumulative distribution function of ground object.In order to evaluate the performance of the proposed algorithm,two hyperspectral remote sensing images are adopted as experimental data.The proposed algorithm is compared with spectral angle mapper (SAM),spectral information divergence (SID) and Euclidean distance (ED) using the product accuracy,user accuracy,overall accuracy,average accuracy and Kappa coefficient.The results show that the proposed algorithm can be applied to hyperspectral image classification effectively. | WANG Ke GU XingFa YU Tao MENG QingYan ZHAO LiMin FENG Li | 2013 | Science China(Technological Sciences)2013,56,4: | 10 |
| 6 | Systematic Identification of the Light-quality Responding Anthocyanin Synthesis-related Transcripts in Petunia Petals显示文摘Previous studies have shown that high light intensity can induce anthocyanin synthesis(AS)in petunia plants.To identifywhich kind of light quality plays a role in inducing such metabolic process,and what transcripts participate in controlling it,we carried out whole-transcriptome sequencing and analysis of petunia petals treated with different light-quality conditions.Among the red and white light treatments,a total of 2205 differentially expressed genes and 15,22,and 20 differentially expressed circRNAs,miRNAs,and lncRNAs,were identified respectively.The AS-related genes,including the structural genes CHSj,F3H,F35H,DFR,and ANS,and the regulatory genes AN4,DPL,PHZ and MYBx were found to be downregulated under red light condition compared with their levels under white light condition.Furthermore,the light photoreceptor Cryptochrome 3(CRY3)and a series of light-dependent genes,such as PIF,HY5,andBBXs,were also determined to respond to the light treatments.The anthocyanin contents in early petunia petals under red light were significantly lower than that under white and blue light.The results of qRT-PCR further confirmed the expression pattern of some AS-related and light-response genes in response to different light quality.Yeast two-hybrid results showed that the key elements in the light signal pathway,HY5 can interact with BBX19,BBX24 and BBX25.And PHZ,the important AS regulator can induce anthocyanin synthesis in response to blue light quality fromtransient expression analysis in petunia petals.These findings presented here not only deepen our understanding of how light quality controls anthocyanin synthesis,but also allow us to explore potential target genes for improving pigment production in petunia flower petals. | Zhenzhu Fu Hongquan Shang Hui Jiang Jie Gao Xiaoyu Dong Huijuan Wang Yanmin Li Limin Wang Jing Zhang Qingyan Shu Yacong Chao Menglan Xu Rui Wang Liangsheng Wang Hechen Zhang | 2020 | Horticultural Plant Journal2020,6,6: | 7 |
| 7 | Experimental Study and Numerical Simulation of Directionally Solidified Turbine Blade Casting显示文摘汽轮机片样品铸造物的方向性的团结过程在工作被调查。可变退却率用一致 rate.A 在一个退却过程并且与其它相比被使用为热放射转移和方向性的团结过程的微观结构模拟的数学模型基于 CA-FD 被开发方法。温度分发和微观结构被模仿并且与试验性的结果相比。迷路的谷物被预言并且与试验性的结果相比。站台的不平的温度分发是迷路的谷物的形成的主要原因。 | Jing YU Qingyan XU Baicheng LIU Jiarong LI Hailong YUAN Haipeng JIN | 2008 | Journal of Materials Science & Technology2008,24,3: | 4 |
| 8 | Analysis of interprovincial trade embodied carbon emissions in Beijing-Tianjin-Hebei and surrounding provinces: based on constructed MRIO Model显示文摘The interprovincial trade embodied carbon emissions plays an important role in the national emission reduction target among China's provinces. Furthermore, it will affect the smooth start-up of the national carbon trade market as well as the implementation of targets in 2030 for dealing with the climate change. Based on constructed MRIO model, this paper analyzes the embodied carbon emission trade flows among Beijing, Tianjin, Hebei and surrounding regions such as Shanxi, Shaanxi, and Inner Mongolia. The results indicate that six provinces have formed different patterns of carbon trade balance, where Beijing, Tianjin, and Hebei provinces are in a deficit position, while the other three provinces are in a surplus position.Beijing, Tianjin, and Hebei have transferred part of the carbon emissions to the other three provinces, which shows greater heterogeneity among various provinces and provincial different sectors. On basis of the conclusions, this paper puts forward some suggestions on provincial decomposition, responsibility distribution, and provincial collaborative reduction for national emission reduction targets. | Jianhui Cong Qingyan Liu Jidong Kang Wenju Li Xiaopei Wang Man Li | 2017 | Chinese Journal of Population,Resources and Environment2017,15,1: | 4 |
| 9 | Ultraviolet-to-microwave room-temperature photodetectors based on three-dimensional graphene foams显示文摘Highly sensitive broadband photodetection is of critical importance for many applications.However,it is a great challenge to realize broadband photodetection by using a single device.Here we report photodetectors(PDs)based on three-dimensional(3 D)graphene foam(GF)photodiodes with asymmetric electrodes,which show an ultra-broadband photoresponse from ultraviolet to microwave for wavelengths ranging from 10~2 to 10~6 nm.Moreover,the devices exhibit a high photoresponsivity of 10~3 A·W^-1,short response time of 43 ms,and3 d B bandwidth of 80 Hz.The high performance of the devices can be attributed to the photothermoelectric(PTE,also known as the Seebeck)effect in 3 D GF photodiodes.The excellent optical,thermal,and electrical properties of 3 D GFs offer a superior basis for the fabrication of PTE-based PDs.This work paves the way to realize ultra-broadband and high-sensitivity PDs operated at room temperature. | YIFAN LI YATING ZHANG YU YU ZHILIANG CHEN QINGYAN LI TENGTENG LI JIE LI HONGLIANG ZHAO QUAN SHENG FENG YAN ZHEN GE YUXIN REN YONGSHENG CHEN JIANQUAN YAO | 2020 | Photonics Research2020,8,3: | 4 |
| 10 | Self-powered,flexible,and ultrabroadband ultraviolet-terahertz photodetector based on a laser-reduced graphene oxide/CsPbBr3 composite显示文摘Self-powered and flexible ultrabroadband photodetectors(PDs)are desirable in a wide range of applications.The current PDs based on the photothermoelectric(PTE)effect have realized broadband photodetection.However,most of them express low photoresponse and lack of flexibility.In this work,high-performance,self-powered,and flexible PTE PDs based on laser-scribed reduced graphene oxide(LSG)∕CsPbBr3 are developed.The comparison experiment with LSG PD and fundamental electric properties show that the LSG∕CsPbBr3 device exhibits enhanced ultrabroadband photodetection performance covering ultraviolet to terahertz range with high photoresponsivity of 100 mA/W for 405 nm and 10 mA/W for 118μm at zero bias voltage,respectively.A response time of 18 ms and flexible experiment are also acquired at room temperature.Moreover,the PTE effect is fully discussed in the LSG∕CsPbBr3 device.This work demonstrates that LSG∕CsPbBr3 is a promising candidate for the construction of high-performance,flexible,and self-powered ultrabroadband PDs at room temperature. | YIFAN LI YATING ZHANG ZHILIANG CHEN QINGYAN LI TENGTENG LI MENGYAO LIHONGLIANG ZHAO QUAN SHENG WEI SHI JIANQUAN YAO | 2020 | Photonics Research2020,8,8: | 3 |
| 11 | Effect of diacylglycerol acyltransferase 2overexpression in 3T3-L1 is associated to an increase in mono-unsaturated fatty acid accumulation显示文摘Background:Fatty acid(FA) composition is the most important parameter affecting the flavor and nutritional value of the meat.The final and the only committed step in the biosynthesis of triglycerides is catalyzed by diacylglycerol acyltransferase 2(DGAT2).The role of DGAT2 in lipid accumulation has been demonstrated in adipocytes,However,little is known about the effect of DGAT2 on the FA composition of these cells.Methods:To investigate the role of DGAT2 in regulating lipid accumulation,FA composition and the expression of adipogenic genes,we cloned the open reading frame of the porcine DGAT2 gene and established 3T3-L1 cells that overexpressed DGAT2.Cells were then cultured in differentiation medium(DM) without FA,with a mixture of FAs(FA-DM),or containing a ^(13)C stable isotope-labeled FA mixture(IFA-DM).The FA composition of adipocytes was analyzed by gas chromatography-mass spectrometry and gas chromatography-isotope ratio mass spectrometry.Quantitative PCR and western blotting were employed to detect expression of adipogenic genes in 3T3-L1 adipocytes cultured with FA-DM for 12 d.Results:The triacylglyceride(TAG) content was significantly higher in 3T3-L1 adipocytes overexpressing DGAT2 than in control cells.When cultured in DM or FA-DM for 12 d,cells overexpressing DGAT2 showed a higher proportion of unsaturated FAs(C16:1 and C18:1).However,when cells overexpressing DGAT2 were cultured with FA-DM for30 min,the FA composition was almost identical to that of controls.Further,the proportion of stable isotope-labeled FAs were similar in 3T3-L1 adipocytes overexpressing DGAT2 and control cells cultured in IFA-DM for 12 d.These results collectively indicate that the higher proportion of mono-unsaturated FAs,C16:1 and C18:1,may originate from de novo FA synthesis but not from the uptake of specific FAs from the medium.This hypothesis is further supported by evidence that both mRNA and protein expression of genes involved in FA synthesis(ACACA,FASN,SCD1,and A-FABP)were significantly higher in cells overexpressing DGAT2 than in control cells.Conclusions:In conclusion,our study revealed that TAG accumulation,the proportion of MUFAs,and the expression of adipogenic genes were higher in 3T3-L1 cells overexpressing DGAT2 than in control cells. | Zhiqi Zhang Gang Shu Xiaotong Zhu Junming Guo Han Cai Songbo Wang Lina Wang Ping Gao Qianyun Xi Yongliang Zhang Li Yuan Qingyan Jiang | 2014 | Journal of Animal Science and Biotechnology2014,5,4: | 3 |
| 12 | Response of PM_(2.5)-bound elemental species to emission variations and associated health risk assessment during the COVID-19 pandemic in a coastal megacity显示文摘The coronavirus(COVID-19)pandemic is disrupting the world from many aspects.In this study,the impact of emission variations on PM_(2.5)-bound elemental species and health risks associated to inhalation exposure has been analyzed based on real-time measurements at a remote coastal site in Shanghai during the pandemic.Most trace elemental species decreased significantly and displayed almost no diel peaks during the lockdown.After the lockdown,they rebounded rapidly,of which V and Ni even exceeded the levels before the lockdown,suggesting the recovery of both inland and shipping activities.Five sources were identified based on receptor modeling.Coal combustion accounted for more than 70%of the measured elemental concentrations before and during the lockdown.Shipping emissions,fugitive/mineral dust,and waste incineration all showed elevated contributions after the lockdown.The total non-carcinogenic risk(HQ)for the target elements exceeded the risk threshold for both children and adults with chloride as the predominant species contributing to HQ.Whereas,the total carcinogenic risk(TR)for adults was above the acceptable level and much higher than that for children.Waste incineration was the largest contributor to HQ,while manufacture processing and coal combustion were the main sources of TR.Lockdown control measures were beneficial for lowering the carcinogenic risk while unexpectedly increased the non-carcinogenic risk.From the perspective of health effects,priorities of control measures should be given to waste incineration,manufacture processing,and coal combustion.A balanced way should be reached between both lowering the levels of air pollutants and their health risks. | Guochen Wang Kan Huang Qingyan Fu Jia Chen Juntao Huo Qianbiao Zhao Yusen Duan Yanfen Lin Fan Yang Wenjie Zhang Hao Li Jian Xu Xiaofei Qin Na Zhao Congrui Deng | 2022 | Journal of Environmental Sciences2022,34,12: | 2 |
| 13 | Characterizing the rock geological time by terahertz spectrum显示文摘In the field of geology,it is necessary to get the information about the rock geological time,which includes absolute geologic age and relative geologic age .Tracing the evolutionary history of the earth is one of the research tasks of earth science.Time,space,material and motivation are the basic elements for studying geological processes and enviromnental evolution,and time is the basis for studying geological problems.A clear understanding of the interaction between the above elements will be able to clearly make sure the evolution of the earth and the conditions of rock formation.Nowadays,it is urgent to get the geochronological data of rocks for wide range comparison,so as to study the evolution trend and development rule of the earth's crust . | WenXiu Leng QingYan Li RiMa Bao Kun Zhao XinYang Miao YiZhang Li | 2019 | Science China(Physics,Mechanics & Astronomy)2019,62,1: | 2 |
| 14 | Synthesis of Ag-SiO_2 composite nanospheres and their catalytic activity显示文摘A simple,mild,and time-saving method is employed to synthesize Ag-SiO2 composite nanospheres with Ag nanoparticles uniformly distributed on the surface of SiO2 nanoparticles.The chemical elements and the morphology of Ag-SiO2 composite nanospheres were analyzed with transmission electron microscopy(TEM),X-ray power diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).On the surface of Ag-SiO2 composite nanospheres,silane coupling agent(KH-550)is introduced as an intermediary to connect the surfaces of SiO2 nanospheres and Ag nanoparticles,which is also helpful for avoiding the aggregation of Ag nanoparticles.It is found that Ag-SiO2 composite nanospheres have very good catalytic properties for the reduction of organic dyes,which may have potential application in wastewater treatment. | HAN QingYan LI GuiAn WANG DeXuan HE EnJie DONG Jun GAO Wei LI JunNa LIU TingZhuo ZHANG ZhongYue ZHENG HaiRong | 2014 | Science China Chemistry2014,57,6: | 2 |
| 15 | Study on Alkaloids in Fructus Hordei Germinatus显示文摘[Objectives]To isolate and analyze alkaloids in Fructus Hordei Germinatus.[Methods]The alkaloids in the Fructus Hordei Germinatus were extracted by ultrasonic technology,and analyzed by the ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS) technique.[Results] According to the mass spectrometry information,compared with the literature reports,the possible structures of seven alkaloids in the Fructus Hordei Germinatus could be inferred.Compounds 1,2 and 3 were organic amine alkaloids,respectively tyramine and N-methyltyramine,hordenine,compounds 4,5,6 and 7 were indole alkaloids,respectively,tryptamine,gramine,harmine,and bufotenidine.The alkaloids in the Fructus Hordei Germinatus were separated by preparative high performance liquid chromatography(p HPLC) technique,a compound was obtained and identified by UPLC-MS/MS and nuclear magnetic resonance(NMR) technique as hordenine.[Conclusions]This experiment is expected to lay a foundation for the development of alkaloids in the Fructus Hordei Germinatus. | Jianheng GUO Guozhu LI Qingyan MENG Jizhong ZHANG | 2018 | Medicinal Plant2018,9,6: | 2 |
| 16 | Sulfur-deficient Co9S8/Ni3S2 nanoflakes anchored on N-doped graphene nanotubes as high-performance electrode materials for asymmetric supercapacitors显示文摘In this paper,Co9S8/Ni3S2 nanoflakes(NFs)with sulfur deficiencies were grown in-situ on N-doped graphene nanotubes(NGNTs).They were successfully prepared through electrodeposition followed by hydrogenation treatment,which is able to act as a self-supported electrode for asymmetric supercapacitors(ASCs).Combining the defect-rich active materials with highly conductive skeletons,the hybrid electrode N-GNTs@sd-Co9S8/Ni3S2NFs show ultrahigh specific capacity of^304 mA hg^-1 and prominent rate capability(capacity retention ratio of^85%even at 100 Ag^-1),and deliver a long cycling lifespan of^1.9%capacitance loss after 10000 cycles.In addition,an ASC was constructed using the as-synthesized composite electrode as the positive electrode and active carbon(AC)as the negative electrode.The fabricated device shows a high energy density of^45.1 Wh kg^-1 at^3.4 kW kg^-1 and superior cycling stability.This work substantiates a smart strategy to fabricate novel composite electrode materials for next-generation supercapacitors by incorporating riched deficiencies into nanostructures. | ZHAO Jian SONG GuanYing YUAN XiangCheng SHEN Tong JIANG QingYan MENG ALan LIN YuSheng LI ZhenJiang LI QingDang | 2020 | Science China(Technological Sciences)2020,63,4: | 2 |
| 17 | Use of laser speckle contrast imaging to reveal changes in temperature and blood perfusion in the skin of healthy subjects after administration of heated moxa sticks and Daiwenjiu ointment显示文摘OBJECTIVE: To investigate the influence of heated moxa sticks( 'moxibustion') and Daiwenjiu ointment(DO) on changes in temperature and blood perfusion volume on the skin of the backs of healthy subjects.METHODS: DO was spread on the left side of the body, and the right side of the body was treated with a heated moxa stick. Images denoting blood perfusion and body temperature were collected 7-8 cm lateral to the spinous process of the sixth thoracic vertebra using laser speckle contrast imaging(LSCI). Data obtained from eight-frame images were analyzed and used to calculate the mean blood perfusion volume. Simultaneously,blood-perfusion images were collected from the body surface and used to compare the change in blood flow on the body surface and the actual position of imaging.RESULTS: After moxibustion, a rapid increase in blood perfusion volume and body temperature was noted in the local skin surface. The maximum blood perfusion volume and body temperature was noted at 20 min(P<0.05). At 80-110 min after the spreading of DO, a gradual increase was noted in blood perfusion volume(P<0.05) and body temperature(P<0.05) compared with the baseline level. The maximum blood perfusion volume was at 110 min.CONCLUSION: Using LSCI, these data revealed a rapid and sharp increase in blood perfusion volume and body temperature after treatment with moxibustion, but the respective changes seen in the DO group were gradual and moderate. | Qingyan Xu Jinsheng Yang Liang Wang Zi Deng Yingying Wang Li Yang Peng Wu Liang Li | 2014 | Journal of Traditional Chinese Medicine2014,34,4: | 2 |
| 18 | Fabricating of Open-cell Porous Al-Si Alloy with Pressure Penetration Casting显示文摘Open-cell porous Al alloy was fabricated by pressure penetration casting. The fabrication ofpreform was studied in detail. When forming temperature is about 700℃ and binder contentis about 10%, preform with high compressive strength is obtained. Good porous Al alloy withpore size (0.5-1.6 mm) and porosity (60%-80%) can be obtained under 100℃ superheatingof liquid metal and about 1.0 MPa applied pressure. The size of the largest sample is up to100 mm in diameter and 100 mm in height. With the help of SEM it was found that the obtainedmaterial is a three-dimension open-cell porous structure with well-distributed and connected witheach other pores. Finally theoretical analysis was carried out to explain the efect of fabricatingprocess. | Xu, Qingyan Chen, Yuyong Li, Qingchun
| 1999 | Journal of Materials Science & Technology1999,15,1: | 2 |
| 19 | Electronic structure of exfoliated millimeter-sized monolayer WSe2 on silicon wafer显示文摘The mono layer WSe2 is in teresting and important for future application in nanoelectronics,spintronics and valleytronics devices,because it has the largest spin splitting and Ion gest valley coherence time among all the known monolayer transition-metal dichalcogenides(TMDs).Toobtain the large-area monolayer TMDs'crystal is the first step to manu facture scalable and high-performance electronic devices.In this letter,we have successfully fabricated millimeter-sized mono layer WSe2 single crystals with very high quality,based on our improved mecha nicalexfoliation method.With such superior samples,using standard high resolution angle-resolved photoemission spectroscopy,we didcomprehe nsive electronic band structure measurements on our mono layer WSe2.The overall band features point it to be a 1.2 eV direct bandgap semico nductor.Its spin splitting of the valence band at K point is found as 460 meV,which is 30 meV less than the corresponding band splitting in its bulk counterpart.The effective hole masses of valence bands are determined as 2.344 me atГ,and 0.529 me as well as 0.532 meat K for the upper and lower branch of splitting ban ds,respectively.And screening effect from substrate is shown to substa ntially impact onthe electronic properties.Our results provide importa nt insights into band structure engineering in mono layer TMDs.Our mono layer WSe2 crystals may constitute a valuable device platform. | Wenjuan Zhao Yuan Huang Cheng Shen Cong Li Yongqing Cai Yu Xu Hongtao Rong Qiang Gao Yang Wang Lin Zhao Lihong Bao Qingyan Wang Guangyu Zhang Hongjun Gao Zuyan Xu Xingjiang Zhou Guodong Liu | 2019 | Nano Research2019,12,12: | 2 |
| 20 | Ratiometric fluorescent detection of acidic pH in lysosome with carbon nanodots显示文摘It is significant for cell physiology to keep the homeostasis of p H, and it is highly demanded to develop ratiometric fluorescent sensors toward p H. In this work, under mild condition, through the electrostatic interaction between carbon nanodots(CDs) and organic molecules, two novel ratiometric fluorescence hybrid nanosensors were fabricated for sensing acidic p H. These nanohybrid systems possess dual emission peaks at 455 and 527 nm under a single excitation wavelength of 380 nm in acidic p H condition.With the increasing of p H, the fluorescence of the 1,8-naphthalimide derivative completely quenches,while the blue fluorescence of CDs keeps constant. Furthermore, the CDsàorganic molecular nanohybrids exhibit excellent anti-disturbance ability, reversible p H sensing ability, and a linear response range in wide p H range respectively. Besides the ability to target lysosome, with one of the nanosensor, stimulated p H change has been successfully tracked in a ratiometric manner via fluorescence imaging. | Yangyang He Zhanxian Li Qingyan Jia Bingjie Shi Hongyan Zhang Liuhe Wei Mingming Yu | 2017 | Chinese Chemical Letters2017,28,10: | 1 |