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Chinese Journal of Chemistry 2002年第5期20卷 424-426页

作者： De‐Zhong Zhu Xing‐Min Song Jian‐Min Dou ying liu Da‐Qi Wang Department of Chemistry Liaocheng Teacher's College Liaocheng 252000

A novel two‐dimensional network dibenzo‐18‐crown‐6 (DB18‐C6) complex: [Na (DB18‐C‐6) (H 2 O) 2 ] [Na (DB18‐C‐6) (SCN) 2 ] has been isolated and characterized by elemental, IR and X‐ray diffraction analysis. The crystal structure belongs to monoclinic, space group P 2 1 /c with cell dimensions a = 1.06178(7), b = 1.40243(8), c = 3.03496(19) nm, β = 90.4220(10)°, V = 4.5292(5) nm 3 , Z=4, D calcd =1.351 g/ cm 3 , F (000) = 1936, R 1 = 0.0369, wR 2 = 0.0821. The most interesting feature in this structure is that complex cation and complex anion form a two‐dimensional network via τ‐τ stacking interactions, hydrogen bonds and electrostatic interactions.

关键词： τ‐τ stacking interactions hydrogen bonds crown ether DB18‐crown‐6 crystal structure

The relationships among perceived organizational support,intention to remain,career success and self-esteem in Chinese male nurses

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International Journal of Nursing Sciences 2015年第4期2卷 389-393页

作者： Jing-ying liu Ji-peng Yang Yang Yang Yan-hui liu School of Nursing Tianjin University of Traditional Chinese MedicineTianjin 300193China School of Acupuncture Tianjin University of Traditional Chinese MedicineTianjin 300193China

Aim:The purpose of this study was to investigate the relationships among perceived organizational support,intention to remain,career success and self-esteem in male nurses in ***:Recently,turnover is considered increasingly more *** nurses could be stabilized by improving their perceived organizational support,career success and ***:A cross-sectional design was used in the present ***:405 full-time male Registered Nurses,from Grade A hospitals in Tianjin,were *** correlation,Cronbach's alpha coefficient and structural equation modelling were conducted in the ***:The results illustrated that self-esteem mediated the relationship between perceived organizational support and career *** success mediated the relationship between self-esteem and intention to ***:Hospitals should pay more attention to the benefits of positive personality trait on working *** is meaningful to enhance perceived organizational support,career success and self-esteem in the working process so that nurses are willing to stay in the current employment.

关键词： Perceived organizational support Intention to remain Career success Self-esteem

Silencing of transcription factor E93 inhibits adult morphogenesis and disrupts cuticle, wing and ovary development in Locusta migratoria

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Insect Science 2022年第2期29卷 333-343页

作者： Xiao-Jian liu Guo Jun Xiao-Yu liang Xue-Yao Zhang Ting-Ting Zhang Wei-Min liu Jian-Zhen Zhang Min Zhang Research Institute of Applied Biology Shanxi UniversityTaiyuanChina

Ecdysone-induced protein 93F(E93)plays important roles during the metamorphosis process in *** this study,a cDNA of the LmE93 gene was identified from the transcriptome of Locusta migratoria,which consists of the 3378-nucleotide open-reading frame(ORF)and encodes 1125 amino acids with helix–turn–helix(HTH)*** transcription quantitative polymerase chain reaction analysis revealed that LmE93 was highest expressed in *** LmE93 expression level was markedly low from the 3rd to 4th instar nymphs,and greatly increased in 1-day-old 5th instar nymphs with a peak on middle nymphal days,then declined in the late nymphal ***,injected dsLmE93 into 4th and 5th instar nymphs greatly reduced LmE93 transcripts,respectively,and prevented the process of metamorphosis,causing supernumerary nymphal ***–eosin staining of the integument showed that the apolysis occurred in advance in 4th instar nymphs,and old cuticle degradation was decreased in dsLmE93-injected locusts of 5th instar *** and no fully developed wings with reduced columns between the anterior and posterior regions were found in N6 and N7 supernumerary *** addition,the development of the ovary in dsLmE93-injected locusts was severely blocked,the yolk was almost not formed and there was no development of *** results indicated that LmE93 play key roles in the metamorphosis,cuticle,wing and ovarian development of locusts.

关键词： expression function Locusta migratoria RNA interference transcription factor E93

Preparation of Molecular Imprinted Copolymer Membrane for Uracil Recognition

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Chinese Chemical Letters 2003年第8期14卷 794-796页

作者： Shao Ling XIA Hong ying WANG Hong SUN Yu Kun liu Shao Kui CAO Material Engineering School of Zhengzhou University Zhengzhou 450052

Uracil molecular imprinted membrane was prepared by phase inversion technique with [P(AN-co-MAA)] copolymer. SEM photograph shows that the resultant membrane has a typical ultrafiltration structure with Water Volume Flux of 3.7?0-5m3/m2穝, and uracil substrate permeation experiment shows that the resultant membrane can bind uracil into its structure, and shows a binding equilibrium.

关键词： Molecular imprinting membrane phase inversion.

Quantitative analysis of C, Si, Mn, Ni, Cr and Cu in low-alloy steel under ambient conditions via laser-induced breakdown spectroscopy

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Plasma Science and Technology 2018年第7期20卷 152-158页

作者： Dan LUO ying liu Xiangyu LI Zhenyang ZHAO Shigong WANG Yong ZHANG Guobiao (Beijing) Test & Certification Co. Ltd Beijing 100088 People's Republic of China Naval Aviation University Yantai 264001 People's Republic of China Shandong Dongyi Photoelectric Instruments Co. Ltd Yantai 264670 People's Republic of China

A diode-pumped solid-state laser （DPSSL） with a high energetic stability and long service life is applied to ablate the steel samples instead of traditional Nd：YAG laser pumped by a xenon lamp, and several factors, such as laser pulse energy, repetition rate and argon flow rate, that influence laser-induced breakdown spectroscopy （LIBS） analytical performance are investigated in detail. Under the optimal experiment conditions, the relative standard deviations for C, Si, Mn, Ni, Cr and Cu are 3.3%-8.9%, 0.9%-2.8%, 1.2%-4.1%, 1.7%-3.0%, 1.1%-3.4% and 2.5%-8.5%, respectively, with the corresponding relative errors of 1.1%-7.9%, 1.0%-6.3%, 0.4%-3.9%, 1.5%-6.3%, 1.2%-4.0% and 1.2%-6.4%. Compared with the results of the traditional spark discharge optical emission spectrometry technique, the analytical performance of LIBS is just a little inferior due to the less stable laser-induced plasma and smaller amount of ablated sample by the laser. However, the precision, detection limits and accuracy of LIBS obtained in our present work were sufficient to meet the requirements for process analysis. These technical performances of higher stability of output energy and longer service life for DPSSL, in comparison to the Q-switch laser pumped by xeon lamp, qualify it well for the real time online analysis for different industrial applications.

关键词： laser-induced breakdown spectroscopy (LIBS) diode-pumped solid-state laser(DPSSL) optical emission spectrometry laser-induced plasma

Parameter study on numerical simulation of corner separation in LMFA-NACA65 linear compressor cascade

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Chinese Journal of Aeronautics 2017年第1期30卷 15-30页

作者： Gao Feng Ma Wei Sun Jinjing Jérome Boudet Xavier Ottavy liu Yangwei Lu Lipeng Shao liang National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power Engineering Beihang University Beijing 100191 China Department of Mechanical Engineering Sciences University of Surrey Guildford GU2 7XH UK School of Aeronautics and Astronautics Shanghai Jiao Tong University Shanghai 200240 China Laboratoire de Mecanique des Fluides et d'Acoustique Ecole Centrale de Lyon Ecully 69134 France

Large-eddy simulation（LES） is compared with experiment and Reynolds-averaged Navier-Stokes（RANS）, and LES is shown to be superior to RANS in reproducing corner separation in the LMFA-NACA65 linear compressor cascade, in terms of surface limiting streamlines,blade pressure coefficient, total pressure losses and blade suction side boundary layer profiles. However, LES is too expensive to conduct an influencing parameter study of the corner *** approach, despite over-predicting the corner separation, gives reasonable descriptions of the corner separated flow, and is thus selected to conduct a parametric study in this paper. Two kinds of influencing parameters on corner separation, numerical and physical parameters, are analyzed and discussed： second order spatial scheme is necessary for a RANS simulation; incidence angle and inflow boundary layer thickness are found to show the most significant influences on the corner separation among the parameters studied; unsteady RANS with the imposed inflow unsteadiness（inflow angle varying sinusoidally with fluctuating amplitude of 0.92°） does not show any non-linear effect on the corner separation.

关键词： Corner separation Influencing parameter LES Linear compressor cascade RANS

Origins of black carbon from anthropogenic emissions and open biomass burning transported to Xishuangbanna, Southwest China

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Journal of Environmental Sciences 2023年第3期125卷 277-289页

作者： Xuyan liu SiwenWang Qianqian Zhang Chunlai Jiang Linlin liang Shihao Tang Xingying Zhang Xiuzhen Han Lin Zhu National Satellite Meteorological Center Beijing 100081China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China Department of Multiphase Chemistry Max Planck Institute for ChemistryMainz 55128Germany Research Center for Total Pollution Load Control and Emission Trading Chinese Academy of Environmental PlanningBeijing 100012China State Key Laboratory of Severe Weather and Key Laboratory for Atmospheric Chemistry Chinese Academy of Meteorological SciencesBeijing 100081China

Black carbon(BC) has importance regarding aerosol composition, radiative balance, and human exposure. This study adopted a backward-trajectory approach to quantify the origins of BC from anthropogenic emissions(BCAn) and open biomass burning(BCBB) transported to Xishuangbanna in 2017. Haze months, between haze and clean months, and clean months in Xishuangbanna were defined according to daily PM_(2.5)concentrations of >75, 35–75, and<35 μg/m^(3), respectively. Results showed that the transport efficiency density(TED) of BC transported to Xishuangbanna was controlled by the prevailing winds in different *** yearly contributions to the effective emission intensity of BCAnand BCBBtransported to Xishuangbanna were 52% and 48%, respectively. However, when haze occurred in Xishuangbanna, the average BCAnand BCBBcontributions were 23% and 77%, respectively. This suggests that open biomass burning(BB) becomes the dominant source in haze months. Myanmar, India, and Laos were the dominant source regions of BC transported to Xishuangbanna during haze months, accounting for 59%, 18%, and 13% of the total, respectively. Furthermore, India was identified as the most important source regions of BCAntransported to Xishuangbanna in haze months, accounting for 14%. The two countries making the greatest contributions to BCBBtransported to Xishuangbanna were Myanmar and Laos in haze months, accounting for 55% and 13%, respectively. BC emissions from Xishuangbanna had minimal effects on the results of the present study. It is suggested that open BB in Myanmar and Laos, and anthropogenic emissions in India were responsible for poor air quality in Xishuangbanna.

关键词： Black carbon Xishuangbanna Effective emission intensity Anthropogenic emissions Open biomass burning

Corrosion Behavior of the Ni-Cr-Fe Base Superalloy GH984G in a Synthetic Coal Ash and Flue Gas Environment

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Acta Metallurgica Sinica(English Letters) 2017年第9期30卷 863-868页

作者： Guang-Ming liu Hua-Chun Yang Qin liang Xiao-Chuan Yang Shan-Ping Ren Jian-Hang Huang School of Materials Science and Engineering Nanchang Hangkong University Dongfang Boiler Group Co. Ltd Material Research Institute

The corrosion behavior of the new Ni-Cr-Fe base superalloy GH984G in a synthetic coal ash and flue gas environments was studied at 700 ℃. The results showed that the corrosion rate was slow during the initial corrosion stage, then followed by a stage of faster mass loss. During the corrosion test, the scale trended to spall slightly, resulting in the formation of corrosion pits on the sample surfaces. The main corrosion products were identified as NiFeCrO4 and a small amount of Cr2O3. The scale microstructure involved the presence of three corrosion layers. The outer layer contained Cr, Ni, Fe, O and a small amount of S. Many micro-cracks were detected in the Cr-rich intermediate oxide layer. The inner corrosion layer was thin and rich in S. Internal sulfidation and internal oxidation occurred in the substrate. Because of its relatively high Cr content, the GH984G superalloy exhibited a good corrosion resistance under the test conditions.

关键词： Ni-Fe-Cr base superalloy Coal ash SO2 Corrosion

Necessary problems in re-emergence of COVID-19

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World Journal of Clinical Cases 2021年第1期9卷 1-7页

作者： Si Chen Lin-Zhu Ren Hong-Sheng Ouyang Shen liu Li-ying Zhang College of Animal Sciences Jilin UniversityChangchun 130062Jilin ProvinceChina Department of Pharmacy Jilin Cancer HospitalChangchun 130000Jilin ProvinceChina

The ongoing pandemic of coronavirus disease 2019 poses a great threat to human *** numerous patients have recovered,re-positive cases have been reported in several *** now,we still know very little about the disease and its pathogen severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Therefore,more attention should be paid to the following aspects,such as postdischarge surveillance,asymptomatic infection,re-evaluation of influenza-like symptoms,and dynamic monitoring of genomic mutation of SARS-CoV-2.

关键词： COVID-19 SARS-CoV-2 Re-positive Follow-up Asymptomatic infection

Time Complexity of the Oracle Phase in Grover’s Algorithm

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American Journal of Computational Mathematics 2024年第1期14卷 1-10页

作者： ying liu Department of Engineering Technology Savannah State University Savannah Georgia

Since Grover’s algorithm was first introduced, it has become a category of quantum algorithms that can be applied to many problems through the exploitation of quantum parallelism. The original application was the unstructured search problems with the time complexity of O(). In Grover’s algorithm, the key is Oracle and Amplitude Amplification. In this paper, our purpose is to show through examples that, in general, the time complexity of the Oracle Phase is O(N), not O(1). As a result, the time complexity of Grover’s algorithm is O(N), not O(). As a secondary purpose, we also attempt to restore the time complexity of Grover’s algorithm to its original form, O(), by introducing an O(1) parallel algorithm for unstructured search without repeated items, which will work for most cases. In the worst-case scenarios where the number of repeated items is O(N), the time complexity of the Oracle Phase is still O(N) even after additional preprocessing.

关键词： Quantum Computing Oracle Amplitude Amplification Grover’s Algorithm