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Communications in Theoretical Physics 2006年第2期45卷 259-261页

作者： GU Zhi-Yu HUANG Bo-Wen qian shang-Wu physics Department Capital Normal University Beijing 100037 China physics Department Peking University Beijing 100871 China

This article uses the phase space path integral method to find the propagator for a particle with a force quadratic in velocity. Two specific canonical transformations has been used for this purpose.

关键词： phase space path integral propagator canonical transformation

Supersymmetric WKB Approximation of Anharmonic Potential V（r）=ar^2＋br^-4＋cr^-6

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Communications in Theoretical Physics 2006年第1X期46卷 37-38页

作者： qian shang-Wu MIAO Chun-Hui GU Zhi-Yu physics Department Peking University Beijing 100871 China physics Department Capital Normal University Beijing 100037 China

This article uses the supersymmetric WKB approximation to obtain the approximate energy levels and wave functions of the anharmonic potential V（r） = ar^2 ＋ br^-4 ＋ cr^-6 in order to tesify the correctness between ... 详细信息

关键词： supersymmetric WKB approximation energy level wave function

Heterogeneous oxidation of SO_2 by O_3-aged black carbon and its dithiothreitol oxidative potential

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Journal of Environmental Sciences 2015年第10期27卷 56-62页

作者： Weiwei Xu qian Li Jing shang Jia Liu Xiang Feng Tong Zhu State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University POTEN Environment Group Co. Ltd.

Ozone（O3） is an important atmospheric oxidant. Black carbon（BC） particles released into the atmosphere undergo an aging process via O3 oxidation. O3-aged BC particles may change their uptake ability toward trace reducing gases such as SO2 in the atmosphere,leading to different environmental and health effects. In this paper, the heterogeneous reaction process between O3-aged BC and SO2 was explored via in-situ diffuse reflectance infrared Fourier transform spectroscopy（DRIFTS）. Combined with ion chromatography（IC）,DRIFTS was used to qualitatively and quantitatively analyze the sulfate product. The results showed that O3-aged BC had stronger SO2 oxidation ability than fresh BC, and the reactive species/sites generated on the surface had an important role in the oxidation of *** humidity or 254 nm UV（ultraviolet） light illumination enhanced the oxidation uptake of SO2 on O3-aged BC. The oxidation potentials of the BC particles were detected via dithiothreitol（DTT） assay. The DTT activity over BC was decreased in the process of SO2 reduction, with the consumption of oxidative active sites.

关键词： Black carbon Ozone SO2 Heterogeneous reaction Oxidative potential Dithiothreitol assay

Modal structure and propagation of internal tides in the northeastern South China Sea

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Acta Oceanologica Sinica 2019年第9期38卷 12-23页

作者： qian Liu Xiaohui Xie Xiaodong shang Guiying Chen Hong Wang School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography Ministry of Natural Resources Hangzhou 310012 China State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

The evolution of energy, energy flux and modal structure of the internal tides (ITs) in the northeastern South China Sea is examined using the measurements at two moorings along a cross-slope section from the deep continental slope to the shallow continental shelf. The energy of both diurnal and semidiurnal ITs clearly shows a ~14-day spring-neap cycle, but their phases lag that of barotropic tides, indicating that ITs are not generated on the continental slope. Observations of internal tidal energy flux suggest that they may be generated at the Luzon Strait and propagate west-northwest to the continental slope in the northwestern SCS. Because the continental slope is critical-supercritical with respect to diurnal ITs, about 4.6 kJ/m^2 of the incident energy and 8.7 kW/m of energy flux of diurnal ITs are reduced from the continental slope to the continental shelf. In contrast, the semidiurnal internal tides enter the shelf because of the sub-critical topography with respect to semidiurnal ITs. From the continental slope to the shelf, the vertical structure of diurnal ITs shows significant variation, with dominant Mode 1 on the deep slope and dominant higher modes on the shelf. On the contrary, the vertical structure of the semidiurnal ITs is stable, with dominant Mode 1.

关键词： South China Sea internal tides propagation scattering modal structure

Moxibustion alleviates decreased ovarian reserve in rats by restoring the PI3K/AKT signaling pathway

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Journal of Integrative Medicine 2022年第2期20卷 163-172页

作者： Hong-xiao Li Ling Shi shang-jie Liang Chen-chen Fang qian-qian Xu Ge Lu qian Wang Jie Cheng Jie Shen Mei-hong Shen College of Acupuncture Moxibustion and TuinaNanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina Key Laboratory of Acupuncture and Medicine Research of Ministry of Education Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina School of Traditional Chinese Medicine&School of Integrated Chinese and Western Medicine Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina

Objective:Moxibustion,a common therapy in traditional Chinese medicine,has potential benefits for treating decreased ovarian reserve(DOR).The present study investigates the protective effect of moxibustion in a rat model of DOR and explores the possible ***:Sixty-four female Sprague-Dawley rats were randomly divided into four groups:control,DOR,moxibustion(MOX),and hormone replacement therapy(HRT).The DOR rat model was established by intragastric administration of 50 mg/kg Tripterygium glycoside suspension(TGS),once daily for 14 *** and HRT treatments were given from the day TGS administration was *** ovarian reserve function was evaluated by monitoring the estrus cycle,morphological changes in ovaries,levels of serum estradiol(E2),follicle-stimulating hormone(FSH),luteinizing hormone(LH),and anti-Mullerian hormone(AMH),pregnancy rate and embryo ***-deoxynucleotidyl transferase-mediated nickend-labeling staining was used to identify ovarian granulosa cell apoptosis,while the protein and m RNA expressions of Bax,B-cell lymphoma-2(Bcl-2),phosphatidylinositol 3-kinase(PI3 K)and protein kinase B(AKT)in ovarian tissues were examined by immunohistochemistry,Western blot and quantitative reverse transcription-polymerase chain ***:Compared with the DOR group,MOX improved the disordered estrous cycle,promoted follicular growth,reduced the number of atresia follicles,increased the concentrations of serum E2 and AMH,and decreased serum FSH and LH *** importantly,the pregnancy rate and embryo numbers in DOR rats were both upregulated in the MOX treatment group,compared to the untreated DOR ***,we found that the MOX group had reduced apoptosis of ovarian granulosa cells,increased Bcl-2 expression and reduced expression of ***,the PI3 K/AKT signaling pathway was triggered by the moxibustion ***:Moxibustion improved ovarian function and suppressed apoptosis of ovarian gra

关键词： Decreased ovarian reserve Moxibustion Phosphatidylinositol 3-kinase Protein kinase B Apoptosis Infertility

Efficient elimination of carbamazepine using polyacrylonitrile-supported pyridine bridged iron phthalocyanine nanofibers by activating peroxymonosulfate in dark condition

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Journal of Environmental Sciences 2024年第3期137卷 224-236页

作者： Zhexin Zhu Wenjie qian Zhiguo shang Xiaoji Ma Zhendong Wang Wangyang Lu Wenxing Chen National Engineering Lab for Textile Fiber Materials and Processing Technology(Zhejiang) Zhejiang Sci-Tech UniversityHangzhou 310018China

The monoaminotrinitro iron phthalocyanine(FeMATNPc)is used to connect with isonicotinic acid(INA)for amide bonding and axial coordination to synthetic a unique catalyst FeMATNPc-INA,which is loaded in polyacrylonitrile(PAN)nanofibers by *** introduction of INA destroys theπ-πconjugated stack structure in phthalocyanine molecules and exposes more active *** FeMATNPc-INA structure is characterized by X-ray photoelectron spectroscopy and UV-visible absorption spectrum,and the FeMATNPcINA/PAN structure is characterized by Fourier transform infrared spectroscopy and X-ray *** FeMATNPc-INA/PAN can effectively activate peroxymonosulfate(PMS)to eliminate carbamazepine(CBZ)within 40 minutes(PMS 1.5 mmol/L)in the *** effects of catalyst dosage,PMS concentration,pH and inorganic anion on the degradation of CBZ are *** has been confirmed by electron paramagnetic resonance,gas chromatography–mass spectroscopy and free radical capture experiments that the catalytic system is degraded by·OH,SO4^(·-)and Fe(IV)=O are the major active species,the singlet oxygen(^(1)O_(2))is the secondary active *** degradation process of CBZ is analyzed by ultra-high performance liquid chromatography-mass spectrometry and the aromatic compounds have been degraded to small molecular acids.

关键词： Pyridine bridged iron phthalocyanine Isonicotinic chloride hydrochloride Efficient elimination Peroxymonosulfate activation Degradation pathway

Neutrophil-to-lymphocyte ratio in sporadic amyotrophic lateral sclerosis

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Neural Regeneration Research 2022年第4期17卷 875-880页

作者： qian-qian Wei Yan-Bing Hou Ling-Yu Zhang Ru-Wei Ou Bei Cao Yong-Ping Chen Hui-Fang shang Department of Neurology Laboratory of Neurodegenerative DisordersWest China HospitalSichuan UniversityChengduSichuan ProvinceChina

The neutrophil-to-lymphocyte ratio(NLR)is considered a robust prognostic biomarker for predicting patient survival outcomes in many ***,it remains unclear whether it can be used as a biomarker for amyotrophic lateral sclerosis(ALS).To correlate NLR with disease progression and survival in sporadic ALS,1030 patients with ALS between January 2012 and December 2018 were included in this *** patients were assigned into three groups according to their NLR values:Group 1(NLR3,n=172[16.7%]).All patients were followed up until April *** in Group 3 had a significantly older onset age,a lower score on the Revised ALS Functional Rating Scale,and rapidly progressing disease ***,faster disease progression rates were associated with higher NLR values(odds ratio=1.211,95%confidence interval[CI]:1.090–1.346,P<0.001)after adjusting for other risk *** with Groups 1 and 2,the survival time in Group 3 was significantly shorter(log-rank P=0.002).The NLR value was considered an independent parameter for the prediction of survival in ALS patients after normalizing for all other potential parameters(hazard ratio[HR]=1.079,95%CI:1.016–1.146,P=0.014).The effects on ALS survival remained significant when adjusted for treatment(HR=1.074,95%CI:1.012–1.141,P_(trend)=0.019)or when considering the stratified NLR value(HR=1.115,95%CI:1.009–1.232,P_(trend)=0.033).Thus,the NLR may help to predict the rate of disease progression and survival in patients with sporadic *** study was approved by the Institutional Ethics Committee of West China Hospital of Sichuan University,China(approval No.2015(236))on December 23,2015.

关键词： amyotrophic lateral sclerosis Cox analysis inflammation lymphocytes monocytes neutrophils prognosis survival rate

Microstructure,crystalline phase and electrical properties of Li_(0.06)(Na_(0.5)K_(0.5))_(0.94)Nb_(1-2x/5)Mg_xO_3 lead-free piezoelectric ceramics

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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 340-346页

作者： Hai-tao Li Bo-ping Zhang qian Zhang Peng-peng shang Gao-lei Zhao School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering Henan University of Science and Technology Luoyang 471003 China

MgO-modified Li0.06（Na0.5K0.5）0.94NbO3O3 （L6NKN） lead-free piezoelectric ceramics were synthesized by normal sintering at a rela- tively low temperature of 1000℃. The crystalline phase, microstructure, and electrical properties of the ceramics were investigated with a special emphasis on the influence of MgO content. The addition of MgO effectively improves the sintembility of the L6NKN ceramics. X-my diffr cfion analysis indicates that the morphotropic phase boundary （MPB） separating orthorhombic and tetragonal phases for the ceramics lies in the range of Mg doping content （x） from 0.3at% to 0.7at%. High electrical properties of the piezoelectric constant （d33=238 pC/N）, planar electromechanical coupling coefficient （kp=41.5%）, relative dielectric constant （εr=905）, and remanent polarization （Pr=38.3 μC/cm2） are obtained from the specimen with x=0.5at%, which suggests that the Li0.06（Na0.5K0.5）0.94Nb（1-2x/5）MgxO3 （x=0.5at%） ceramic is a promising lead-free piezoelectric material.

关键词： lead-flee piezoelectric ceramics sinterability sintering morphotropic phase boundary

Incorporating Convexity in Bond Portfolio Immunization Using Multifactor Model:A Semidefinite Programming Approach

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Journal of the Operations Research Society of China 2018年第1期6卷 3-23页

作者： Wei Zhu Cai-Hong Zhang qian Liu Shu-shang Zhu Department of Finance and Investment Sun Yat-Sen Business SchoolSun Yat-Sen UniversityGuangzhou 510275China Ping An Securities Company Ltd Beijing 100033China

Bond portfolio immunization is a classical issue in finance. Since Macaulaygave the concept of duration in 1938, many scholars proposed different kinds of duration immunization models. In the literature of bond portfolio immunization usingmultifactor model, to the best of our knowledge, researchers only use the first-orderimmunization, which is usually called as duration immunization, and no one hasconsidered second-order effects in immunization, which is well known as “convexity” in the case of single-factor model. In this paper, we introduce the second-orderinformation associated with multifactor model into bond portfolio immunization andreformulate the corresponding problems as tractable semidefinite programs. Bothsimulation analysis and empirical study show that the second-order immunization strategies exhibit more accurate approximation to the value change of bonds and thusresult in better immunization performance.

关键词： Immunization Duration Convexity Multifactor model Semidefinite programming

Thermal-oxidation mechanism of dioctyl adipate base oil

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Friction 2016年第1期4卷 29-38页

作者： Xuzheng qian Yaling XIANG Hongfei shang Bingxue CHENG Shengpeng ZHAN Jian LI State Key Laboratory of Special Surface Protection Materials and Application Technology Wuhan Research Institute of Materials Protection Wuhan 430030 China State Key Laboratory of Tribology Tsinghua University Beijing 100084 China

The ester base oil of dioctyl adipate (DOA) was oxidized in an oven at 200 degrees C for 30 h, and variations in the physicochemical and tribological properties were studied. To investigate the thermal-oxidation mechanism, the thermal-oxidation products were analyzed by gas chromatography-mass spectrometry (GC-MS), and the thermal-oxidation process was simulated using visual reactive force field molecular dynamics (ReaxFF MD). The results indicated that the total acid number (TAN) increased significantly because of the presence of 14% carboxylic acids and low molecular weight monoesters. The tribological properties were improved by the formation of the strongly polar carboxylic acids. Additionally, the increase in kinematic viscosity was limited due to the formation of high molecular weight polymerization products and low molecular weight degradation products. Thermal-oxidative degradation and polymerization mechanisms were proposed by combining ReaxFF MD simulations and GC-MS results.

关键词： dioctyl adipate GC-MS physicochemical properties tribological properties ReaxFF MD