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Journal of Mountain Science 2017年第4期14卷 771-781页

作者： WANG Xin-gang WANG Jia-ding gu Tian-feng LIAN Bao-qin State Key Laboratory of Continental Dynamics Department of Geology Northwest University School of Geology Engineering and Surveying Chang' an University

After water is impounded in a reservoir, rock mass in the hydro-fluctuation belt of the reservoir bank slope is subject to water saturation- dehydration circulation （WSDC）. To quantify the rate of change of rock mechanical properties, samples from the Longtan dam area were measured with uniaxial compression tests after different numbers （1, 5, 10, 15, and 20） of simulated WSDC cycles. Based on the curves derived from these tests, a modified Hock- Brown failure criterion was proposed, in which a new parameter was introduced to model the cumulative damage to rocks after WSDC. A case of an engineering application was analyzed, and the results showed that the modified Hock-Brown failure criterion is useful. Under similar WSDC-influenced engineering and geological conditions, rock mass strength parameters required for analysis and evaluation of rock slope stability can be estimated according to this modified Hoek-Brown failure criterion.

关键词： Modified Hoek-Brown criterion Reservoir bank slope Hydro-fluctuation belt Water saturation-dehydration circulation Damage

Reversible Properties of Monoid Crossed Products

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Communications in Mathematical Research 2018年第1期34卷 36-46页

作者： Yin Yue Zhao Liang gu qin-qin School of Mathematics & Physics Anhui University of Technology School of Mathematics Sciences Nanjing Normal University

We study the reversible properties of monoid crossed products. The new class of strongly CM-reversible rings is introduced and characterized. This class of rings is a generalization of those of strongly reversible rings, skew strongly reversible rings and strongly M-reversible rings. Some well-known results on this subject are generalized and extended.

关键词： monoid crossed product strongly reversible ring strongly CM-reversible ring

Semiannual oscillation,annual oscillation,quasibiennial oscillation,and solar cycle variation of the OH airglow emission in the mesopause region

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Earth and Planetary Physics 2024年第3期8卷 479-496页

作者： Sheng-Yang gu Dong Wang YuSong qin Liang Tang YaFei Wei XianKang Dou Electronic Information School Wuhan UniversityWuhan 430072China School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China

The vertically integrated emission rate,centroid altitude,peak emission rate,and peak height of the hydroxyl(OH)airglow were calculated from Thermosphere Ionosphere Mesosphere Energetics and Dynamics(TIMED)/Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)observations to study the seasonal and interannual variations in the intensity and location of the OH *** emission rate is inversely proportional to the height of the emission,with the semiannual oscillation dominating at low latitudes and the annual oscillation dominating at higher *** OH emission is modulated by the quasibiennial oscillation at the equator,and the quasibiennial oscillation signal is weak at other *** represented the vertical transport of atomic oxygen by using atomic oxygen concentrations obtained from a global atmospheric model,the Specified Dynamics Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension *** with the amplitudes of the migrating diurnal tide(DW1)calculated from temperature data observed by TIMED/SABER,we found that both the vertical transport of atomic oxygen and DW1 amplitudes in the equatorial region exhibit semiannual oscillation and quasibiennial oscillation,which have a strong correlation with the variations in the amplitude and phase of semiannual oscillation and quasibiennial oscillation in OH *** is likely that the DW1 affects the vertical transport of atomic oxygen that is involved in the reaction to produce O3,thus affecting the OH *** analyzed the relationship between OH emission and solar activity by using the solar radio flux at 10.7 cm as a proxy for solar *** results showed that the OH emission is well correlated with solar activity,and the modulation of OH emission by solar activity has a significant latitudinal *** small correlation between emission height and solar activity indicates that solar activity modulates OH emission mainly thr

关键词： OH airglow semiannual oscillation quasibiennial oscillation solar activity diurnal tide

Analysis on small-earthquake composite fault plane solutions from 1961 to 1999 in Xinfengjiang reservoir area

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Acta Seismologica Sinica(English Edition) 2004年第3期17卷 287-295页

作者： guO gui-an(郭贵安) LIU Te-pei(刘特培) qin Nai-gang(秦乃岗) CHEN Li-fen(陈丽芬) Shenzhen Seismostation Shenzhen 518003 China Earthquake Administration of Guangdong Province Guangzhou 510070 China Earthquake Administration of Guangdong Province Guangzhou 510070 China Earthquake Administration of Guangdong Province Guangzhou 510070 China

To understand the earthquake characteristics in Xinfengjiang (XFJ for short) reservoir area, we collected the small earthquakes occurred in the area from 1961 to 1999. We segmented this 40-year period, parted the research region and calculated the composite fault plane solution of each block, disscussed the effect characteristics of stress field of water pressure using Mohrs stress circle. The final result shows that the main rupture pattern was very different before and after the M = 6.1 main shock, changing from strike slip to normal rupture. The maximum principal stress axes of composite fault plane solutions are characterized by synchronous change with water level.

关键词： Xinfengjiang reservoir Mohrs stress circle focal mechanism CLC number: P315.3 Document code: A

Preparation and reducing-responsive property of a novel functional polyurethane nanoemulsion

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Chinese Chemical Letters 2020年第1期31卷 292-294页

作者： He qin Hong Zhang Xiaoteng Zhou Danfei gu Lingxiao Li Chengyou Kan Department of Chemical Engineering and Key Laboratory of Advanced Materials of Ministry of Education of China Tsinghua University

As a kind of stimuli-responsive materials,the disulfide-containing material has received a tremendous amount of interest.A novel functional disulfide-containing waterborne polyurethane(DS-WPU)nanoemulsion was prepared via a one-step in situ phase inverse emulsification technique and its reducing-responsive prope rty was investigated using dithiothreitol as the *** showed that the DS-WPU nanoemulsion had a uniform particle size in nanoscale and a good film-forming characteristic,and the DS-WPU latex film exhibited great responsiveness along with a self-assembled behavior in the reducing environment to form WPU emulsion again,including a long-to-short process of the polymer chains.

关键词： Polyurethane Disulfide bond Nanoemulsion Reducing-responsiveness Self-assembly

High-performance floating-gate organic phototransistors based on n-type core-expanded naphthalene diimides

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Chinese Chemical Letters 2023年第3期34卷 465-468页

作者： Xianrong gu Yang qin Su Sun Lidan guo Xiangwei Zhu Xiangnan Sun Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China

In the field of organic phototransistor, achieving both broad-spectral and high photosensitivity has always been a big challenge. The innovation of device structure has previously proven to be a possible solution to this problem. Here in this study, a novel organic phototransistor based on a high mobility n-type small molecule as the conducting layer and an isolated bulk heterojunction light-absorbing layer as the floating gate has been demonstrated in this study. With the special designed device structure, the phototransistor shows extremely high sensitivity to broad spectral and weak light irradiation, and the photoresponsivity and photocurrent/dark-current ratio of the device can reach up to 4840 mA/W and 1.8×10~5 *** conclusion, this study suggests a potential way to obtain high-performance phototransistors at room temperature, which will further promote the commercial application of organic phototransistors.

关键词： Organic phototransistor Bulk heterojunction n-Type small molecule Broad spectral photoresponse Weak light irradiation

Journal of Genetics and Genomics in 2023:progresses and beyond

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Journal of Genetics and Genomics 2024年第1期51卷 1-2页

作者： Xiu-fen Song Xiaoxuan guo Jing Zhao Yutian Zhang Yuan qin Jianru Zuo Journal of Genetics and Genomics Institute of Genetics and Developmental BiologyChinese Academy of Sciences&the Genetics Society of ChinaBeijing 100101China

Journal of Genetics and Genomics(JGG),launched in 1974,celebrates its 50th birthday in *** continuous support from our authors,reviewers,readers,and the editorial board,JGG has made remarkable progress in the past year by publishing 122 papers covering major disciplines in life sciences and medical genetics with exciting *** is worthwhile to note that we have recruited 66 young talents to join JGG as junior editors,resulting in significant improvement in manuscript evaluation and journal ***,we summarize major progresses reported in JGG in 2023 fromaneditorial view.

关键词： journal beyond promotion

SLIP VELOCITY MODEL OF POROUS WALLS ABSORBED BY HYDROPHOBIC NANOPARTICLES SIO_2

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Journal of Hydrodynamics 2007年第3期19卷 365-371页

作者： gu Chun-yuan DI qin-feng FANG Hai-ping Shanghai Institute of-Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Shanghai Institute of Applied Physics Chinese Academy of Scinese Shanghai 201800 China

According to new slip effects on nanopatterned interfaces, the mechanism of enhancing water injection into hydrophobic nanomaterial SiO2 was proposed. When Hydrophobic Nanoparticles（HNPs）are adsorbed on surfaces of porous walls, hydrophobic nanoparticles layers are formed instead of hydrated layer, and slip effects appear on the pore wall when a driving pressure is applied to the rock cores sample. It makes fluid to move more quickly and the flow capacity increases greatly. Experiments on changing wettability of porous walls were conducted, and the phenomenon that porous walls surfaces were adsorbed by nanoparticles was validated with the Environment Scan Electron Microscopy（ESEM）. The results of displacement experiments show that flowing resistance is greatly reduced, and water-phase effective permeability is increased by 47 % averagely after being treated by nanofluid. These results indicate that the slip effect may occur on nanoparticle film of porous walls. Based on this new mechanism of enhancing water injection about hydrophobic nanomaterial SiO2, a slip velocity model in uniform porous media was introduced, and some formulas for the ratio of slip length to radius, slip length ,stream slip velocity and flux increment were deduced. and calculated results indicate that the ratio of slip length to radius is about 3.54%-6.97%, and the slip length is about 0.024 μ m -0.063 μ m. The proposed model can give a good interpretation for the mechanisms of enhancing water injection with the HNPs.

关键词： hydrophobic nanomaterial SiO2 mechanism of enhancing water injection velocity slip model core displacement experiments adsorption wettability

Effect of CXCR4 pretreated with ultrasound-exposed microbubbles on accelerating homing of bone marrow mesenchymal stem cells to ischemic myocardium in AMI rats

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Asian Pacific Journal of Tropical Medicine 2015年第9期8卷 751-756页

作者： Jun-Yi gu Hui-fen Shi Xiu-Li Gao qing-qing Ma Bo Zhang Department of Ultrasound in Medicine East Hospital Tongji University School of Medicine

Objective: To investigate the role and potential mechanism of CXCR4 in promoting targeted homing of bone marrow mesenchymal stem cells(BMSCs) with ultrasound-exposed microbubbles(UM) pretreatment. Methods: Third generation BMSCs were divided into four groups control group, ultrasound(US) group, UM group and ultrasound-exposed microbubbles plus catalase group. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and protein expression, respectively. Third generation BMSCs were labeled with Fluo-α/AM and divided into three groups: control group, US group and UM group, and flurorescence intensities in the cells were observed immediately, 5 min and 15 min after intervention underflurorescence microscope. The calcium iron levels in the cells were analyzed. BMSCs were divided into i ve group: group A without calcium in the medium, group B, group C, group D and group E containing calcium chloride with concentration of l mol, 2 mol, 4mol, anti-calciurn-sensing receptor antibody, respectively. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and proteins expression of the third generation BMSCs of each group, respectively. Results: The levels of CXCR4 m RNA transcription and protein expression between US group and control group had no statistically signii cant dif erence(P>0.05) shown by RT-PCR and western blot; the transcription level in the UM group was signii cantly higher than that in US group and control group(P0.05), which in the cells of UM group was signii cantly higher than that in the cells of both US group and control group(P<0.05). Compared to group A, expressions of CXCR4 of group B to D were signii cantly increased in

关键词： Ultrasound-exposed microbubbles Bone marrow mesenchymal stem cells CXCR4 Calciumion

Recent advances in remote C(sp^(3))-H functionalization via chelating group-assisted metal-catalyzed chain-walking reaction

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Chinese Chemical Letters 2024年第11期35卷 99-110页

作者： Jian Han Li-Li Zeng qin-Yu Fei Yan-Xiang Ge Rong-Hui Huang fen-Er Chen School of Pharmacy Changzhou UniversityChangzhou 213164China Engineering Center of Catalysis and Synthesis for Chiral Molecules Department of ChemistryFudan UniversityShanghai 200433China Shenzhen Research Institute of Nanjing University Shenzhen 518057China

Aliphatic C(sp^(3))-H moieties are ubiquitous in numerous organic *** functionalization of inert C(sp^(3))-H bonds is a powerful and straightforward approach for the efficient construction of diverse carbon-carbon or carbon-heteroatom *** group directed metal-catalyzed remote functionalization of readily available alkenes has emerged as an appealing strategy for rapidly accessing various value-added aliphatic *** the aid of directing groups,variousα-,β-andγ-functionalized alkanes could be synthesized smoothly with excellent *** preferred formation of a stable five-or six-membered metallacycle intermediate terminates the chain-walking at a specific methylene site,which serves as the driving force for excellent site-selective migratory *** review herein is aimed at summarizing the recent progress on the metal-catalyzed regiodivergent functionalization of unactivated alkenes by merging alkene isomerization and cross-coupling with the assistance of directing *** but not least,the current situations and future directions in this field are highlighted and discussed.

关键词： Chelating group Chain-walking Regiodivergent Unactivated alkenes C(sp^(3))-H functionalization Transition-metal catalysis