检索结果-南通市图书馆

Atomic Force Microscopy of Surface Reconstructed SrTiO3 Vicinal Substrates for Epitaxial Growth of YBa_(2)Cu_(3)O_(7-δ) Thin Films

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1999年第11期16卷 853-855页

作者： HU wen-fei LI Lin WANG Tian-sheng LIU Wei TAO Hong-jie TIAN Yong-jun CHEN Ying-fei National Laboratory for Superconductivity Chinese Academy of SciencesBeijing 100080 Institute of Physics Chinese Academy of SciencesBeijing 100080 Department of Material Science Yanshan UniversityQinhuangdao 066004

SrTiO_(3)(001) vicinal substrates of miscut 1°, 3°, and 6° toward the (001) plane were annealed at 800-1000°C in pure flowing O_(2) for 6h and examined by atomic force microscopy. The high temperature annealed vicinal SiTiO_(3)(001) displayed arrays of straight steps and smooth terraces. The step heights vary from about 2 to 6 unit cell depending on the annealing temperatures. At 1000°C, step bunching becomes obvious. The height steps of 1 unit cell are difficult to be observed by our atomic force microscopy. The YBa2Cu3O7-δ thin film grows epitaxially on the step-terrace surface with c-axis orientation by magnetron sputtering in the two-dimensional island mode. Prospect of step-flow growth is being discussed.

关键词： steps straight island

Linkages among the functional traits,insect visitation rate and seed set of Gentiana taxa on the Tibetan Plateau

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Mountain Science 2022年第8期19卷 2312-2321页

作者： DAI wen-fei GAO Rui HE Meng-ying YANG Yu-lian LI Fang-lan MU Jun-peng Ecological Security and Protection Key Laboratory of Sichuan Province Mianyang Normal UniversityMianyang 621000China Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China

Maximum plant height(H_(max)),stem tissue mass density(SD),leaf mass per area(LMA),and relative growth rate(RGR)have all been linked to flowering ***,it is still unknown whether these functional traits varying with flowering phenology are related to other floral traits associated with pollinator preference and reproductive *** investigated the relationship between vegetative and floral traits,as well as the rates of insect visitation and seed set of fiveGentiana species in eastern Tibetan *** results showed that flowering onset and flowering offset time were all found to be positively correlated with the H_(max),SD,and LMA,but negatively correlated with the *** onset time was positively correlated with corolla diameter and pollen grain number,whereas was negatively correlated with flower number and flower *** rates of insect visitation were positively related to flowering onset time,pollen grain number,corolla diameter,and seed set,but negatively related to flower number and *** flowering species have higher RGR but lower SD,LMA andH_(max),as well as smaller flowers,fewer pollen grains,longer flower longevity,and lower insect visitation rates than late-flowering plant *** findings indicate that floral traits are related to vegetative traits in Gentiana *** these plant trait relationships were associated with pollinator preference,and plant reproductive success of eastern Tibetan *** speculate that these traits relationships are likely adaptive in unpredictable and often pollinator-limited environments in the Tibet alpine meadows.

关键词： Life history strategy Mating system Reproductive efficiency Alpine plant

Influence of Rare-Earth Elements on ElectricalProperties of Pd

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1994年第6期10卷 459-462页

作者： fei wen Yuantao NING Huaizhi ZHAO and Deguo DENG(Kunming Institute of Precious Metals, Kunming, 650221, China) Kunming Inst of Precious Metals Kunming China

The influence of RE (RE = La, Ce. Pr. Nd, Sm, Eu, Gd. Tb. Dy, Er, Yb) additives with dilute concentrations on the electrical properties of Pd has been studied. All RE elements increase the specific resistivity (ρ) and decrease the resistance temperature coefficient (α) of Pd. and (ρ.α) Pd-RE ls equal to (ρ· α)*** RE elements before Gd reduce the thermo-emf of Pd on Cu. other heavy RE enhance the *** experimental data of normalized Pd-0.1 at.-%RE alloys indicate that the effect of light RE additives on the specific resistivity of Pd is larger than that of heavy RE and Ce. Eu and Yb show anomalous strong effect. The valence and atomic size are main factors influencing the electrical properties.

关键词： Influence of Rare-Earth Elements on ElectricalProperties of Pd Eu

Efficient C_(2)-Symmetric Chiral Schiff Bases for Lanthanide-catalyzed Asymmetric Hydrogenation of Acetophenone

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2006年第10期17卷 1297-1300页

作者： Peng fei YAN wen Bin SUN Guang Ming LI Chun Hong NIE Zheng Yu YUE School of Chemistry and Materials Science Heilongjiang University Harbin 150080

An array of C2-symmetric chiral Schiff bases of substituted salicylaldehyde （1R, 2R）-1, 2-cyclohexanediamine and （R）-（＋）-2, 2＇-diamino-1, 1＇-binaphthalene, incorporated with lanthanide complexes, have been applied as catalysts for asymmetric hydrogenation of acetophenone for the first time. Highly enantioselective product with 90% enantiomeric excess （e.e.） was obtained when the catalyst, hybridized by the bulky electron-donating 3, 5-di-tert-butyl substituted Schiff base （2） and SmCl3.4THF, was employed.

关键词： Chiral Schiff base lanthanide (HI) complexes asymmetric hydrogenation acetophenone 2-propanol.

Pits on the Surfaces of Epitaxial c-Axis YBa2Cu3O7-δ Thin Films Grown on Vicinal SrTiO3 Substrates

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2001年第1期18卷 91-93页

作者： HU wen-fei LI Lin ZHAO Xin-Jie LIU Wei CHEN Ying-fei WANG Tian-Sheng QIU Xiang-Gang Institute of Physics&Center for Condensed Matter Physics Chinese Academy of SciencesBeijing100080 Department of Material Science Yanshan UniversityQinhuangdao 066004 CREST Japan Science and Technology Cooperation3-4-1 OkuboShinjukuTokyo 169Japan

The reoccurrence of pits has been found on the surfaces of c-axis YBa2CusO7-δ(YBCO)films grown epitaxially on 10℃vicinal SrTiOs substrates by pulsed laser *** are always associated with films with a stepterrace structure,while polycrystalline films have no *** formation is attributed to the large interfacial stress induced by vicinal substrate and oxygen deficiency of the YBCO film during the tetragonal-to-orthorhombic(TO)phase transition,which cannot be released by forming twins,and leads to rupturing of the film *** reducing the oxidation partial pressure for the T-O phase transition to 80 Pa,no pits were formed,and the YBCO film is superconducting at 60K.

关键词： deposition. surface. film

Interleukin-22 receptor 1 is expressed in multinucleated giant cells:A study on intestinal tuberculosis and Crohn’s disease

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2019年第20期25卷 2473-2488页

作者： Zi-Qi Yu wen-fei Wang You-Chao Dai Xin-Chun Chen Jian-Yong Chen Department of Gastroenterology and Hepatology Jiangxi Provincial People’s HospitalNanchang 330006Jiangxi ProvinceChina Jiangxi Medical College Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Microbiology and Immunology Shenzhen University Health Science CenterShenzhen 518000Guangdong ProvinceChina Department of Pharmaceutical/Medicinal Chemistry Institute of PharmacyFriedrich Schiller UniversityJena 07743Germany

BACKGROUND It is challenging to distinguish intestinal tuberculosis from Crohn’s disease due to dynamic changes in epidemiology and similar clinical characteristics. Recent studies have shown that polymorphisms in genes involved in the interleukin (IL)- 23/IL-17 axis may affect intestinal mucosal immunity by affecting the differentiation of Th17 cells. AIM To investigate the specific single-nucleotide polymorphisms (SNPs) in genes involved in the IL-23/IL-17 axis and possible pathways that affect susceptibility to intestinal tuberculosis and Crohn's disease. METHODS We analysed 133 patients with intestinal tuberculosis, 128 with Crohn’s disease, and 500 normal controls. DNA was extracted from paraffin-embedded specimens or whole blood. Four SNPs in the IL23/Th17 axis (IL22 rs2227473, IL1β rs1143627, TGFβ rs4803455, and IL17 rs8193036) were genotyped with TaqMan assays. The transcriptional activity levels of different genotypes of rs2227473 were detected by dual luciferase reporter gene assay. The expression of IL-22R1 in different intestinal diseases was detected by immunohistochemistry. RESULTS The A allele frequency of rs2227473 (P = 0.030, odds ratio = 0.60, 95% confidence interval: 0.37-0.95) showed an abnormal distribution between intestinal tuberculosis and healthy controls. The presence of the A allele was associated with a higher IL-22 transcriptional activity (P < 0.05). In addition, IL-22R1 was expressed in intestinal lymphoid tissues, especially under conditions of intestinal tuberculosis, and highly expressed in macrophage-derived Langhans giant cells. The results of immunohistochemistry showed that the expression of IL-22R1 in patients with Crohn's disease and intestinal tuberculosis was significantly higher than that in patients with intestinal polyps and colon cancer (P < 0.01). CONCLUSION High IL-22 expression seems to be a protective factor for intestinal tuberculosis. IL-22R1 is expressed in Langhans giant cells, suggesting that the IL-22/IL-22R1 s

关键词： Crohn's disease Intestinal tuberculosis Single-nucleotide polymorphism Interleukin-22 Interleukin-22 receptor 1 Multinucleated giant cells

Ankylosing spondylitis coexisting with Clonorchis sinensis infection: A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2024年第5期12卷 1018-1024页

作者： Tian-Xin Yi Wei Liu wen-fei Leng Xiao-Chuan Wang Liang Luo Department of Rheumatology Traditional Chinese Medicine Hospital Dianjiang ChongqingChongqing 408300China Department of Orthopaedic Traditional Chinese Medicine Hospital Dianjiang ChongqingChongqing 408300China Department of Chinese Medicine The People's Hospital of Yubei District of Chongqing CityChongqing 401120China

BACKGROUND Ankylosing spondylitis(AS)is a chronic immune-mediated inflammatory *** prevailing theory links AS onset to infections in susceptible ***,infections may impair the immune *** studies have investigated links between AS and various infections-bacterial,viral,fungal,and other microorganism ***,limited attention has been given to the association between AS and Clonorchis sinensis(***)*** SUMMARY A 27-year-old male with a 10-yr history of AS presented to our hospital with inflammatory lower back pain as the primary *** years ago,the patient had achieved a stable condition after treatment with biological ***,he experienced a recurrence of lumbosacral pain with an unexplained cause 10 d before hospital admission.A lumbosacral magnetic resonance imaging(MRI)scan revealed bone marrow edema in the left sacroiliac joint,and laboratory indicators were ***,the presence of *** eggs was detected in the *** patient was prescribed praziquantel,resulting in the disap-pearance of *** eggs in subsequent routine stool tests and relief from lumbosacral pain.A follow-up MRI scan performed after 4 months revealed a reduction in bone marrow edema around the left sacroiliac *** *** infections could potentially trigger the exacerbation of *** should pay attention to investigating the presence of *** Ankylosing spondylitis(AS)is a chronic inflammatory and rheumatic disease resulting from an imbalance between innate and acquired immune responses[1].While it can affect any part of the spine,its primary symptoms are persistent back pain and stiffness in the lower back and *** prevalence of AS per 10000 individuals is 23.8 in Europe,31.9 in North America,16.7 in Asia,10.2 in Latin America,and 7.4 in Africa[2].Infections commonly occur in the first 3 months and may act as potential triggers for the

关键词： Ankylosing spondylitis Clonorchis sinensis Parasites Infection Case report

Optical and X-Ray Observations of MAXI J1820+070 During the Early Outburst Phase in 2018:Zooming in the Low Frequency QPOs

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2022年第4期22卷 106-113页

作者： Dong-Ming Mao wen-fei Yu Ju-Jia Zhang Zhen Yan Stefano Rapisarda Xiao-Feng Wang Jin-Ming Bai Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects CASKunming 650216China Physics Department Tsinghua UniversityBeijing 100084China Beijing Planetarium Beijing Academy of Sciences and TechnologyBeijing 100044China

We report a further investigation of the optical low frequency quasi periodic oscillations(LF QPOs)detected in the black hole transient MAXI J1820+070 in the 2018 observations with the YFOSC mounted on Lijiang 2.4 m telescope(LJT).In addition,we make use of the Insight-HXMT/HE observations to measure the properties of the quasi-simultaneous X-ray LF QPOs of MAXI J1820+070 on the same *** compared the centroid frequency,the full width at half maximum(FWHM)and the fractional rms of the LF QPOs in both wavelength *** found that the centroid frequency of the optical QPO is at a frequency of 51.58 m Hz,which is consistent with that of the X-ray LF QPO detected on the same day within 1 m *** also found that the FWHM of the optical LF QPO is significantly smaller than that of the X-ray LF QPO,indicating that the optical QPO has a higher *** quasi-simultaneous optical and the X-ray LF QPO at a centroid frequency of about 52 m Hz suggests that the actual mechanisms of these LF QPOs as the Lense-Thirring precession should work in the vicinity of a radius of about 80-117 gravitational radii(R_(g)=GM/c^(2),M is the mass of the black hole)from the black hole if the QPO frequency is related to a proxy of the orbital frequency in the accretion fiow as the Lense-Thirring precession model ***,the apparent higher coherence of the optical QPO favors that it is a more original signal as compared with the X-ray QPO.

关键词： X-ray stars Low mass binary stars X-ray transient sources

Successful treatment of aortic dissection with pulmonary embolism:A case report

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2022年第16期10卷 5394-5399页

作者： Xu-Guang Chen Sheng-Yi Shi Yun-Yan Ye Huan Wang wen-fei Yao Lan Hu Department of Emergency Ruijin Hospital Affiliated to Medical College of Shanghai Jiaotong UniversityShanghai 201800China

BACKGROUND Aortic dissection(AD)and pulmonary embolism(PE)are both life-threatening *** of their conflicting treatments,treatment becomes difficult when they occur together,and there is no standard treatment *** SUMMARY A 67-year-old man fell down the stairs due to syncope and was brought to our hospital as a confused and irritable patient who was uncooperative during the physical *** examination of the head,chest and abdomen by computed tomography revealed a subdural hemorrhage,multiple rib fractures,a hemopneumothorax and a renal *** was admitted to the Emergency Intensive Care Unit and given a combination of oxygen therapy,external rib fixation,analgesia and enteral *** patient regained consciousness after 2 wk but complained of abdominal pain and dyspnea with an arterial partial pressure of oxygen of 8.66 *** tomography angiograms confirmed that he had both AD and *** subsequently performed only nonsurgical treatment,including nasal high-flow oxygen therapy,nonsteroidal analgesia,amlodipine for blood pressure control,beta-blockers for heart rate *** weeks after admission,the patient improved and was discharged from the *** Patients with AD should be alerted to the possibility of a combined PE,the development of which may be associated with aortic *** patients with type B AD combined with low-risk PE,a nonsurgical,nonanticoagulant treatment regimen may be feasible.

关键词： Aortic dissection Pulmonary embolism Treatment Case report