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SUPERCRITICAL CARBON DIOXIDE ASSISTED SYNTHESIS OF AMPHIPHIliC GRAFT COPOLYMERS BASED ON POLY(STYRENE-CO-MAleIC ANHYDRIDE) WITH METHOXYL POLY(ETHYleNE GLYCOL) SIDE CHAINS

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Chinese Journal of Polymer Science 2012年第2期30卷 173-180页

作者： jian-hua wang li-ping Zhu Zhuan Yi jian-hua li You-yi Xu Bao-ku Zhu MOE Key Laboratory of Macromolecule Synthesis and functionalization MOE Engineering Research Center of Membrane and Water Treatment TechnologyDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Supercritical carbon dioxide （scCO2） was used as a reaction medium in synthesizing amphiphilic graft copolymers composed of poly（styrene-co-maleic anhydride）（SMA） backbones and methoxyl poly（ethylene glycol）（MPEG） side chains via esterification. The synthesized copolymers were characterized by Fourier transform infrared spectroscopy （FTIR）, gel permeation chromatography （GPC）, IH-NMR, thermo-gravimetric analysis （TGA） and differential scanning calorimetric analysis （DSC）. The gelation phenomenon was suppressed effectively by tuning reaction conditions. The influences of scCO2 temperature and pressure on the conversion of anhydride were investigated. It was found that the highest conversion ratio occurred at 80~C under a constant pressure of 14 MPa or 26 MPa. With the increase of scCO2 pressure, the conversion ratio increased first, and then leveled off. The conversion ratio of anhydride could be controlled by regulating the reaction conditions. It was also revealed that using low molecular weight MPEG brought a high conversion ratio of anhydride.

关键词： Supercritical carbon dioxide Poly(styrene-co-maleic anhydride) Poly(ethylene glycol) Amphiphilic graftcopolymer.

Synthesis and Structure of a Manganese(Ⅱ) Complex: [Mn_2·(dinitrobenzoic acid)_4·(1,10-phen)_2]_n

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Chinese Journal of Structural Chemistry 2007年第2期26卷 139-142页

作者： wang jian huaNG Mei-hua liU ping CHENG wen-Dan ZHANG li-Mei fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China 不详

The title compound, [Mn2·（dinitrobenzoic acid）4·（1,10-phen）2]n, has a linear chain structure containing binuclear [Mn2·（dinitrobenzoic acid）4（1,10-phen）2] repeat units. It crystallizes in the triclinic system, space group Pi with a = 7.9261（8）, b = 12.1329（15）, c = 14.847（2）A, α = 103.845（5）, β = 101.424（5）, γ = 92.618（4）°, Mr= 657.37, V = 1352.3（2）A^3, Z = 2, De= 1.614 g/cm^3, F（000） = 666,μ = 0.567 mm^-1, the final R = 0.0407 and wR = 0.1015 for 4081 observed reflections with I 〉 2σ（I）. The Mn atom is six-coordinated by two N and four O atoms, forming a slightly distorted octahedral geometry. All Mn-O and Mn-N bond distances range from 2.093（2） to 2.310（2）A. Two adjacent octahdral units are bridged together by two pairs of bi-monodentate carboxyl groups of different dinitrobenzoic acids to form an eight-membered ring with chair-typed configuration, thus generating a one-dimensional chain along the a axis.

关键词： crystal structure manganese complex eight-membered ring one-dimensional chain

Study of temporal evolution of emission spectrum in a steeply rising submillimeter burst

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Research in Astronomy and Astrophysics 2016年第1期16卷 67-72页

作者： jian-ping li Ai-hua Zhou Xin-Dong wang Key Laboratory of Dark Matter and Space Astronomy Chinese Academy of Sciences Nanjing 210008 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China School of Public Administration Hohai University Nanjing 210098 China

The temporal evolution of a spectrum during a steeply rising submillimeter（THz） burst that occurred on 2003 November 2 was investigated in detail for the first *** show that the flux density of the THz spectrum increased steeply with frequency above 200 *** average rising rates reached a value of 235 sfu GHz^（-1）（corresponding to spectral index α of 4.8） during the *** flux densities reached about 4 000 and 70 000 sfu at 212 and 405 GHz at the maximum phase,*** emissions at 405 GHz maintained such a continuous high level that they largely exceeded the peak values of the microwave（MW） spectra during the main *** studies suggest that only energetic electrons with a low-energy cutoff of~ 1 MeV and number density of ~ 10~6-10~8 cm^（-3） can produce such a strong and steeply rising THz component via gyrosynchrotron radiation based on numerical simulations of burst spectra in the case of a nonuniform magnetic *** electron number density N,derived from our numerical fits to the THz temporal evolution spectra,increased substantially from 8 ×10~6 to 4 × 10~8 cm^（-3）,i.e.,the N value increased 50 times during the rise *** the decay phase it decreased to 7 ×10~7 cm^（-3）,i.e.,it decreased by about five times from the maximum *** total electron number decreased an order of magnitude from the maximum phase to the decay ***,the variation in amplitude of N is only about one time in the MW emission source during this burst,and the total electron number did not decrease but increased by about 20%during the decay ***,we find that the THz source radius decreased by about 24%while the MW source radius,on the contrary,increased by 28%during the decay phase.

关键词： Sun: submillimeter burst -- Sun: energetic electrons -- Sun: radio source size

Diagnostics from three rising submillimeter bursts

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Research in Astronomy and Astrophysics 2016年第2期16卷 97-104页

作者： Ai-hua Zhou jian-ping li Xin-Dong wang Key Laboratory of Dark Matter and Space Astronomy Chinese Academy of Sciences Purple Mountain Observatory Chinese Academy of Sciences School of Public Administration Hohai University

In this paper we investigate three novel rising submillimeter （THz） bursts that occurred sequen- tially in Super Active Region NOAA 10486. The average rising rate of the flux density above 200 GHz is only 20 sfu GHz-1 （corresponding to spectral index α of 1.6） for the THz spectral components of the 2003 October 28 and November 4 bursts, but it attained values of 235 sfu GHz-1 （α = 4.8） in the 2003 November 2 burst. The steeply rising THz spectrum can be produced by a population of highly relativistic electrons with a low-energy cutoff of 1 MeV, but it only requires a low-energy cutoff of 30 keV for the two slowly rising THz bursts, via gyrosynchrotron （GS） radiation based on our numerical simulations of burst spectra in the magnetic dipole field case. The electron density variation is much larger in the THz source than in the microwave （MW） source. It is interesting that the THz source radius decreased by 20%-50% during the decay phase for the three events, but the MW source increased by 28% for the 2003 November 2 event. In the paper we will present a formula that can be used to calculate the energy released by ultrarel- ativistic electrons, taking the relativistic correction into account for the first time. We find that the energy released by energetic electrons in the THz source exceeds that in the MW source due to the strong GS radi- ation loss in the THz range, although the modeled THz source area is 3-4 orders smaller than the modeled MW source one. The total energies released by energetic electrons via the GS radiation in radio sources are estimated, respectively, to be 5.2 × 10^33, 3.9 × 10^33 and 3.7 × 10^32 erg for the October 28, November 2 and 4 bursts, which are 131, 76 and 4 times as large as the thermal energies of 2.9 × 10^31, 2.1 × 10^31 and 5.2 × 10^31 erg estimated from soft X-ray GOES observations.

关键词： Sun submillimeter emission -- Sun energetic electrons -- Sun radio source environment

Recent advances in CRISPR-based genome editing technology and its applications in cardiovascular research

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Military Medical Research 2023年第6期10卷 862-880页

作者： Zhen-hua li Jun wang Jing-ping Xu jian wang Xiao Yang State Key Laboratory of Proteomics Beijing Proteome Research CenterNational Center for Protein SciencesBeijing Institute of LifeomicsBeijing 100071China Yaneng BIOScience(Shenzhen)Co. Ltd.Shenzhen 518102GuangdongChina

The rapid development of genome editing technology has brought major breakthroughs in the fields of life science and medicine. In recent years, the clustered regularly interspaced short palindromic repeats(CRISPR)-based genome editing toolbox has been greatly expanded, not only with emerging CRISPR-associated protein(Cas) nucleases, but also novel applications through combination with diverse effectors. Recently, transposon-associated programmable RNA-guided genome editing systems have been uncovered, adding myriads of potential new tools to the genome editing toolbox. CRISPR-based genome editing technology has also revolutionized cardiovascular research. Here we first summarize the advances involving newly identified Cas orthologs, engineered variants and novel genome editing systems, and then discuss the applications of the CRISPR-Cas systems in precise genome editing, such as base editing and prime editing. We also highlight recent progress in cardiovascular research using CRISPR-based genome editing technologies, including the generation of genetically modified in vitro and animal models of cardiovascular diseases(CVD) as well as the applications in treating different types of CVD. Finally, the current limitations and future prospects of genome editing technologies are discussed.

关键词： Genome editing CRISPR-Cas system Base editing Prime editing Transposon-associated genome editing Cardiovascular disease Heart Blood vessel Gene therapy

Na^+ and Water Uptake in Relation to the Radial Reflection Coefficient of Root in Arrowleaf Saltbush Under Salt Stress

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Journal of Integrative Plant Biology 2007年第9期49卷 1334-1340页

作者： Xin-fu Bai jian-Jun Zhu ping Zhang Yan-hua wang li-Qun Yang lei Zhang College of life Sciences Ludong University Yantai 264025 China

The response of halophyte arrowleaf saltbush （Atriplex triangularis Willd） plants to a gradient of salt stress were investigated with hydroponically cultured seedlings. Under salt stress, both the Na^＋ uptake into root xylem and negative pressures in xylem vessels increased with the elevation of salinity （up to 500 mol/m^3） in the root environment. However, the increment in negative pressures in root xylem far from matches the decrease in the osmotic potential of the root bathing solutions, even when the osmotic potential of xylem sap is taken into consideration. The total water potential of xylem sap in arrowleaf saltbush roots was close to the osmotic potential of root bathing solutions when the salt stress was low, but a progressively increased gap between the water potential of xylem sap and the osmotic potential of root bathing solutions was observed when the salinity in the root environment was enhanced. The maximum gap was 1.4 MPa at a salinity level of 500 mol/m^3 without apparent dehydration of the tested plants. This discrepancy could not be explained with the current theories in plant physiology. The radial reflection coefficient of root in arrowleaf saltbush decreased with the enhanced salt stress was and accompanied by an increase in the Na^＋ uptake into xylem sap. However, the relative Na^＋ in xylem exudates based on the corresponding NaCl concentration in the root bathing solutions showed a tendency of decrease. The results showed that the reduction in the radial reflection coefficient of roots in the arrowleaf saltbush did not lead to a mass influx of NaCl into xylem when the radial reflection coefficient of the root was considerably small; and that arrowleaf saltbush could use small xylem pressures to counterbalance the salt stresses, either with the uptake of large amounts of salt, or with the development of xylem pressures dangerously negative. This strategy could be one of the mechanisms behind the high resistance of arrowleaf saltbush plants to

关键词： anti-osmosis arrowleaf saltbush (Atriplex triangularis Willd) radial reflection coefficient of root salt stress xylem pressure

Sands modeling constrained by high-resolution seismic data

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1858-1863页

作者： ZHANG Feng li Zhi-ping wang He-lin WU jian TAN Zhen-hua School of Energy Resources China University of Geology Beijing 100083 China Institute of Petroleum Exploration and Development Dagang Oilfield Tianjin 300280 China Shallow Water Exploration and Development Company Dagang Oilfield Tianjin 300280 China Institute of Petroleum Exploration and Development PetroChina Company Limited Beijing 100083 China

In the phase of field evaluation, the changing of interwell reservoir may be out of control if the geological model was built only on well data due to few existing wells. The uncertainty of the interwell reservoir interpolation based only on well data can be decreased by comprehensive utilization of geological, logging and seismic data, especially by using highly relative seismic properties from 3D seismic data adjusted by well point data to restrict interpolation of geological properties. A 3D-geological model which takes the sand body as the direct modeling object was built through stacking the structure, reservoir and water/oil/gas properties together in 3D space.

关键词： Reservoir geological modeling Seismic inversion Sand control modeling

Carbon and oxygen behavior in the RH degasser with carbon powder addition

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 681-688页

作者： jian-long Guo li-hua Zhao Yan-ping Bao Shuai Gao Min wang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

For ultra-low-carbon(ULC)steel production,the higher oxygen content before Ruhrstahl-Heraeus(RH)decarburization(de-C)treatment could shorten the de-C time in the RH ***,this would lead to oxidation rates being exceeded by molten steel production,affecting ULC steel surface *** this work,a carbon powder addition(CPA)process was proposed to reduce the dissolved oxygen content at the end of RH de-C through addition of carbon powder to molten steel in the vacuum *** and oxygen behavior during the CPA and conventional process was then *** results demonstrated that the de-C rate with CPA was lower compared to the conventional process,but the carbon content at the end of de-C presented no *** de-C reaction for CPA process took place in the four reaction sites:(1)within the bulk steel where the spontaneous CO bubbles form;(2)splashing area on the liquid steel surface;(3)Ar bubble surface;(4)molten steel *** CPA process could significantly reduce the dissolved oxygen content at the end of de-C,the sum content of FeO and MnO in the slag,the aluminum consumption,and the defect rate of rolled *** was beneficial in improving ULC steel cleanliness.

关键词： ultra-low-carbon steel ruhrstahl-Heraeus degasser carbon powder de-C pre-deoxidization

DNA Methylation and Birth Weight: a Genome-wide Analysis

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Biomedical and Environmental Sciences 2017年第9期30卷 667-670页

作者： MAO li li XIAO Xin hua ZHANG Qian ZHENG Jia li wen Hui YU Miao ZHANG hua Bing ping Fan XU jian ping wang Xiao Jing Department of Endocrinology Key Laboratory of Endocrinology Ministry of Health Peking Union Medical College Hospital Diabetes Research Center of Chinese Academy of Medical Sciences & Peking Union Medical College Department of Endocrinology Civil Aviation General Hospital

The study illustrate the inner correlation between global DNA methylation variation and different birth weights. Infant birth weight was used to identify cases and controls. Cord blood and placentas were collected. We performed DNA methylation profiling of bisulphite‐converted DNA. We have identified many differentially methylated Cp G sites in experimental groups; these sites involved in hundreds of signalings. Among these, more than ten pathways were referred to the glucose and lipid metabolism. Methylation changes in the insulin‐signaling pathway（ISP）, adipocytokine signaling pathway（ASP） and MAPK signaling pathway are involved in the fetal programming of diabetes.

关键词： DNA Methylation and Birth Weight ASP LBW DNAmethylation