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Rare Metals 2016年第2期35卷 177-183页

作者： yu-Hao Zhai yu-Juan zhang Yi Peng Sheng-Mao zhang ping-yu zhang Xiao-Min zhang Key Laboratory of Ministry of Education for Special Functional Materials Henan University College of Materials and Mineral Resources Xi’an University of Architecture and Technology

nc-Ti C/a-C：H nanocomposite films were prepared by filtered cathodic arc technique. The influence of C_2H_2/Ar flow ratio on the composition, structure, and mechanical properties of films was investigated by X-ray photoelectron spectroscopy（XPS）, X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）,Raman spectroscopy, nanoindentation, and ball-on-disc tribometry. The films show a nanocomposite structure in which Ti C crystallites are embedded in the amorphous matrix of a-C：H phase. C content in films increases with the flow ratio of C_2H_2/Ar, simultaneously, the crystallite size of TiC decreases. Contrary to the nc-Ti C/a-C：H films deposited by magnetron sputtering in which the sp3 C content increases with C_2H_2 flow rate, the increase of C_2H_2 flow rate leads to the increase of sp2 C content in films deposited by filtered cathodic arc technique. The nc-Ti C/a-C：H films deposited by cathodic arc technique have a pronounced hardness maximum of 30 GPa under the C_2H_2/Ar flow ratio of 12. Tribological performance of films is controlled by the sp2 content in films. Higher sp2 content promotes the formation of graphite-like transfer layer during sliding,and results in lower wear rate and friction coefficient.

关键词： Nanocomposite films Tribological performance Hardness

Poor outcomes of delirium in the intensive care units are amplified by increasing age: A retrospective cohort study

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World Journal of Emergency Medicine 2021年第2期12卷 117-123页

作者： Wen Gao yu-ping zhang Jing-fen Jin Nursing Department School of MedicineZhejiang UniversityHangzhou 310058China Nursing Department the Second Affi liated Hospital of Zhejiang University School of MedicineHangzhou 310009China

BACKGROUND: Delirium in patients in intensive care units(ICUs) is an acute disturbance and fluctuation of cognition and consciousness. Though increasing age has been found to be related to ICU delirium, there is limited evidence of the effect of age on delirium outcomes. The aim of this study is to investigate the relationship between age categories and outcomes among ICU delirium ***: Data were extracted from the electronic ICU(e ICU) Collaborative Research Database with records from 3,931 patients with delirium. Patients were classified into non-aged(<65 years), youngold(65–74 years), middle-old(75–84 years), and very-old(≥85 years) groups. A Cox regression model was built to examine the role of age in death in ICU and in hospital after controlling covariates. RESULTS: The sample included 1,667(42.4%) non-aged, 891(22.7%) young-old, 848(21.6%) middle-old, and 525(13.3%) very-old patients. The ICU mortality rate was 8.3% and the hospital mortality rate was 15.4%. Compared with the non-aged group, the elderly patients(≥65 yeras) had higher mortality at ICU discharge(χ2=13.726, P=0.001) and hospital discharge(χ2=56.347, P<0.001). The Cox regression analysis showed that age was an independent risk factor for death at ICU discharge(hazard ratio [HR]=1.502, 1.675, 1.840, 95% confidence interval [CI] 1.138–1.983, 1.250–2.244, 1.260–2.687;P=0.004, 0.001, 0.002 for the young-, middle-and very-old group, respectively) as well as death at hospital discharge(HR=1.801, 2.036, 2.642, 95% CI 1.454–2.230, 1.638–2.530, 2.047–3.409;all P<0.001).CONCLUSIONS: The risks of death in the ICU and hospital increase with age among delirious patients.

关键词： Intensive care Delirium Aging Mortality

RF power and I/Q imbalance calibration in B3G/4G MIMO-OFDM systems

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 89-93,124页

作者： LI Ya-zhuo ZHOU Ming-yu zhang ping Wireless Technologies Innovation Institute Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Radio frequency （RF） front-end nonidealities in multi-input and multi-output （MIMO） systems are more serious than in single-input and single-output systems and must be calibrated. According to the effects of RF power and in-phase/quadrature-phase （I/Q） imbalance, calibration methods for multi-input and multi-output-orthogonal frequency division multiplexing （MIMC-OFDM） systems in transmitter and interference in receiver are improved, respectively, in this article Furthermore, a calibration scheme including I/Q imbalance errors and amplitude variations is proposed and implemented in the B3G/4G time division duplex communication system. Simulation results show that the calibration algorithms are feasible, and the bit error rate （BER） performances for MIMO-OFDM systems are improved after calibrations.

关键词： calibration, B3G/4G MIMO-OFDM, front-end, I/Q imbalance

A novel TOA estimation method with effective NLOS error reduction

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 32-37页

作者： zhang Yi-heng CUI Qi-mei LI yu-xiang zhang ping Key Laboratory of Universal Wireless Communications Beijing University of Posts and Telecommunications Ministry of Education Wireless Technology Innovation Institute (WTI) Beijing 100876 China

It is well known that non-line-of-sight （NLOS） error has been the major factor impeding the enhancement of accuracy for time of arrival （TOA） estimation and wireless positioning. This article proposes a novel method of TOA estimation effectively reducing the NLOS error by 60%, comparing with the traditional timing and synchronization method. By constructing the orthogonal training sequences, this method converts the traditional TOA estimation to the detection of the first arrival path （FAP） in the NLOS multipath environment, and then estimates the TOA by the round-trip transmission （RTT） technology. Both theoretical analysis and numerical simulations prove that the method proposed in this article achieves better performance than the traditional methods.

关键词： TOA estimation NLOS error B3G

Rapid Preparation of Monolithic Columns for Capillary Electrochromatography Separation

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Chinese Chemical Letters 2006年第6期17卷 813-816页

作者： Wen Jun GONG Yi Jun zhang yu ping zhang Seong Ho CHOI Henan Institute of Science and Technology Xinxiang 453003 Department of Chemistry Hannam University Daejon South Korea

Fritless packed silica gel columns were prepared using sol-gel technology, The part of a 75 μm i.d. capillary was filled with a mixture of methacryloxypropyltrimethoxysilane, toluene and hydrochloric acid. Four different photoinitiators such as benzoin methyl ether, Irgacure 819, Irgacure 1700 and Irgacure 1800 were added in the presence or absence of sodium dodecyl sulfate during the polymerization process. The above eight solutions were irradiated at 365 nm about 5-10 min to prepare the porous monolithic sol-gel columns by a one-step process.

关键词： Monolithic columns electrochromatography photopolymerized sol-gel.

Entanglement for a Bimodal Cavity Field Interacting with a Two-Level Atom

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Communications in Theoretical Physics 2009年第7期52卷 133-136页

作者： LIU Jia CHEN Zi-yu BU Shen-ping zhang Guo-Feng Department of Physics Beijing University of Aeronautics and Astronautics Beijing 100083 China

Negativity has been adopted to investigate the entanglement in a system composed of a two-level atom anda two-mode cavity *** of Kerr-like medium and the number of photon inside the cavity on the entanglementare *** results show that atomic initial state must be superposed,so that the two cavity field modes can ***,we also conclude that the number of photon in the two cavity mode should be *** interactionbetween modes,namely,the Kerr effect,has a significant negative *** that the atom frequency and thecavity frequency have an indistinguishable effect,so a corresponding approximation has been made in this *** may be useful for quantum information in optics systems.

关键词： negativity Kerr-like medium Jaynes-Cummings model

Zhikang Capsule Ameliorates Inflammation, Drives Polarization to M2 Macrophages, and Inhibits Apoptosis in Lipopolysaccharide-induced RAW264.7 Cells

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Current Medical Science 2021年第6期41卷 1214-1224页

作者： Sheng-liang XIN Xia YANG yu-ping zhang Ke-shu XU Department of Infectious Diseases Peking University First HospitalBeijing 100034China Department of Gastroenterology Wuhan Asia General HospitalWuhan 430056China Department of Gastroenterology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Objective:To explore the anti-inflammatory effect of the traditional Chinese medicine Zhikang capsule(ZKC)on lipopolysaccharide(LPS)-induced RAW264.7 ***:Safe concentrations of ZKC(0.175,0.35,and 0.7 mg/mL)were used after the half-maximal inhibitory concentration(IC_(50))of RAW264.7 cells was calculated through the CCK-8 *** addition,the optimal intervention duration of ZKC(0.7 mg/mL)on RAW264.7 cells was determined to be 6 h,since all proinflammatory mediators[tumor necrosis factor-alpha(TNF-α),interleukin-1 beta(IL-1β),inteleukin-6(IL-6),cyclooxygenase-2(COX-2),inducible nitric oxide synthase(iNOS),and monocyte chemotactic protein-1(MCP-1)]had a decreasing tendency and relatively down-regulated mRNA expression levels as compared with other durations(4,8,and 12 h).RAW264.7 cells were pretreated with ZKC at various concentrations(0.175,0.35 and 0.7 mg/mL)for 6 h and then stimulated with LPS(1 μg/mL)for an additional 12 ***:In terms of inflammation,ZKC could reverse LPS-induced upregulation of TNF-α,IL-1β,IL-6,COX-2,iNOS,and MCP-1 at both the mRNA and protein levels in RAW264.7 cells in a dose-dependent *** terms of the NF-κB signaling pathway,ZKC could reduce phosphorylated p65 and promote M2 polarization of RAW264.7 cells under LPS stimulation in a dose-dependent ***,ZKC exhibited a protective effect on macrophages from ***:ZKC exhibited obvious antiinflammatory and anti-apoptotic effects on LPS-induced RAW264.7 cells at the cellular level,and a weakened NF-κB signaling pathway may be a potential significant target.

关键词： Zhikang capsule macrophage RAW 264.7 inflammation apoptosis nuclear factor kappa B

Novel Method of Preparation of Monolithic Columns for Fast Separation byγ-Ray Irradiation

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Chinese Chemical Letters 2006年第11期17卷 1485-1488页

作者： yu ping zhang Wen Jun GONG Li Qun FAN Yi Jun zhang Kwang Pill LEE Henan Institute of Science and Technology Xinxiang 453003 Department of Chemistry Graduate School Kyungpook National University South Korea

A porous monolithic sol-gel column with the solution of methacryloxypropyltrimethoxysilane in toluene with an acid catalyst was prepared in the presence and absence of sodium dodecyl sulfate. In situ polymerization was carded out by γ-ray irradiation within the capillary. The γ-radiation-initiated synthesis could generate radicals directly on the monomer avoiding use of any initiator. The chromatographic behavior of the capillary monolithic columns were studied in the modes of CEC, p-CEC and low pressure-driven separation, all the tests exhibited reversed-phase character. It provided a viable alternative to either thermally initiated or photo polymerization method for the preparation of monolithic columns.

关键词： Monolithic columns electrochromatography γ-ray irradiation polymerization.

Knickkopf (LmKnk) is required for chitin organization in the foregut of Locusta migratoria

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Insect Science 2024年第5期31卷 1412-1424页

作者： Rong-Rong yu Jia-Qi Duan Xiao-Ming Zhao Mureed Abbas yu-ping zhang Xue-Kai Shi Nan Chen Jian-Zhen zhang College of Biological Sciences and Technology Taiyuan Normal UniversityJinzhongShanxiChina Shanxi Key Laboratory of Nucleic Acid Biopesticides Institute of Applied BiologyShanxi UniversityTaiyuanShanxiChina Guangmeiyuan R&D Center Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied TechnologySouth China Normal UniversityMeizhouGuangdongChina

The foregut,located at the front of the digestive tract,serves a vital role in in-sects by storing and grinding food into small *** innermost layer of the foregut known as the chitinous intima,comes into direct contact with the food and acts as a protec-tive barrier against abrasive ***(Knk)is required for chitin organization in the chitinous exoskeleton,tracheae and *** its significance,lttle is known about the biological function of Knk in the *** this study,we found that LmKnk was stably expressed in the foregut,and highly expressed before molting in Locusta *** ascertain the biological function of LmKnk in the foregut,we synthesized specific double-stranded LmKnk(dsLmKnk)and injected it into *** findings showed a significant decrease in the foregut size,along with reduced food intake and accumulation of residues in the foregut after dsLmKnk *** observations revealed that newly formed intima became thinner and lacked chitin ***,fluores-cence immunohistochemistry revealed that LmKnk was located in the apical region of new intima and epithelial *** together,this study provides insights into the biological function of LmKnk in the foregut,and identifies the potential target gene for exploring biological pest management strategies.

关键词： biological function chitin organization foregut intima Knickkopf RNA interference

Drag reduction and shear resistance properties of ionomer and hydrogen bond systems based on lauryl methacrylate

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Petroleum Science 2011年第3期8卷 357-364页

作者： yu ping Li Changyu zhang Changqiao Chen Shiwei Fang Shu Sun Hui School of Chemistry and Chemical Engineering Shandong University Jinan 250061 China

Based on molecular dynamics simulation results, a lauryl methacrylate polymer with drag reduction and shear resistance properties was designed, and synthesized by emulsion polymerization using 2-vinyl pyridine and methyl methacrylate as the polar polymerization monomer. After ionization of lauryl methacrylate polymer, an ion-dipole interaction based drag reduction agent （DRA） was obtained. The existence of ion-dipole interaction was proven through characterization of the drag-reducing agent from its infrared （IR） spectrum. The pilot-scale reaction yield of the DRA under optimum conditions was investigated, and the drag reduction and shear resistance properties were measured. The results show that： l） The ion-dipole or hydrogen bonding interaction can form ladder-shaped chains, therefore the synthesized DRA has shear resistance properties; 2） The larger the molecular weight （MW） and more concentrated the distribution of MW, the better the drag reduction efficiency and the performance of the ionomer system was superior to that of the hydrogen bonding system; 3） With increasing shear frequency, the drag-reduction rates of both the DRAs decreased, and the drag reduction rate of the ionomer system decreased more slowly than of the corresponding hydrogen bonding system. From the point of view of drag reduction rate and shear resistance property, the ionomer system is more promising than the hydrogen bonding system

关键词： Molecular design ion-dipole interaction hydrogen bonding drag reduction rate shearresistance property