ANALYSIS OF ANOMALOUS CHARACTERS OF THE TIME-LATITUDE RESIDUALS OF YUNNAN OBSERVATORY BEFORE MAJOR EARTHQUAKES

LI XIAOMING,TIAN JUN,HU Hur,KAN RONGU The Korean Astronomical Society 1996 Journal of The Korean Astronomical Society Vol.29 No.suppl1

Research on Rapid Detection Method of Dry Matter Content in Raw Milk Based on Mid-infrared Spectrum

Xiaoming Li,Guicheng Huo,Yan Wang,Qingming Kong,Hongmin Sun 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.9

This paper takes raw milk as research object, and using mid-infrared spectrum analysis method rapidly tests dry matter in raw milk through establishing quantitative analysis model. First of all, researchers collect 84 kinds of raw milk which is different areas and varieties in Heilongjiang province, and classify 84 samples into calibration sets and validation sets by standard chemical testing and spectral scanning on raw milk, and calibration sets contain 64 samples, and validation sets contain 20 samples. Then, respectively selecting SPA and GA characteristic wavelength after treating by smoothing denoising method which window size is 11 points, and establishing PLS model and model demonstration. Eventually, researchers draw the conclusion that SPA wavelength selection method which value of m_max is 10 and GA wavelength selection method which value of Evaluat is 10d can effectively improve validation set model precision, but precision of the latter is higher and characteristic wavelength point reduces from 352 to 10, The calibrating determination coefficient R2 of model is 0.8092155, root mean square error (RMSEC ) is 0.1206172. Validation set determination coefficient R2 is 0.8620867, the root mean square error (RMSEC) is 0.0950656, and relative standard deviation RSD<3%. These prove that the method for rapid testing of raw milk components is feasible.

Controlling oxygen vacancies and properties of ZnO

Xiaoming Li,Jizhong Song,Yanli Liu,Haibo Zeng 한국물리학회 2014 Current Applied Physics Vol.14 No.3

Intrinsic defects in semiconductors play crucial roles on their electrical and optical properties. In this article, we report on a facile method to control concentration of oxygen vacancies inside ZnO nanostructures and related physical properties based on adjustment of thermal transformation conditions from ZnO2 to ZnO, including annealing atmosphere and temperature. ZnO2 spheres assembled with nanoparticles were formed through the reaction between zinc nitrate and hydrogen peroxide. Significantly, it was found that the adopted temperature and atmosphere have remarkable impact on the concentration of oxygen vacancies, which was revealed by the variations of featured Raman scattering peaks at 584 cm1. Furthermore, with the increase of oxygen vacancies inside ZnO, the optical band-gap was found to red-shift 350 meV and the room-temperature ferromagnetism became stronger up to 1.6 emu/mg. The defect formation and evolution were discussed according to the chemical equilibrium of decomposition reaction under special local heating environment. This work demonstrated that ZnO2 decomposition is an effective process to control the defect states inside ZnO and related properties.

Research on Rapid Detection Method of Protein and Fat in Raw Milk Based on Mid-infrared Spectrum

Xiaoming Li,Guicheng Huo,Yan Wang,Hongmin Sun,Qingming Kong 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.10

In this paper raw milk was taken as the research object, using mid-infrared spectrum analysis method rapidly tests protein and fat content in raw milk through establishing quantitative analysis model. First of all, researchers collect 84 kinds of raw milk which is different areas and varieties in Heilongjiang province, and classify 84 samples into calibration sets and validation sets by standard chemical testing and spectral scanning on protein and fat, and calibration sets contain 64 samples, and validation sets contain 20 samples. Then, denoising by second derivative method which window size is 17 points, and selecting method by comparing SPA and GA characteristic wavelength respectively, and establishing PLS model and model demonstration. Eventually, researchers draw the conclusion that SPA wavelength selection method which value of m_max is 10 and GA wavelength selection method which value of Evaluat is 10d can effectively improve validation set model precision, but precision of the former is higher and characteristic wavelength is least, and its characteristic wavelength point reduces from 220 to 4, R2 of protein model validation set is 0.8010929, RMSEP is 0.0207505, R2 of fat model validation set is 0.91007989, RMSEP is 0.045329, relative standard deviation RSD<3%. These prove that the method for rapid testing of raw milk components is feasible.

The characteristic of the synonymous codon usage and phylogenetic analysis of hepatitis B virus

Xiaoming Qi,Chaojun Wei,Yonghong Li,Yu Wu,Hui Xu,Rui Guo,Yanjuan Jia,Zhenhao Li,Zhenhong Wei,Wanxia Wang,Jing Jia,Yuanting Li,Anqi Wang,Xiaoling Gao 한국유전학회 2020 Genes & Genomics Vol.42 No.7

Background Hepatitis B virus (HBV) infection is a crucial medical issue worldwide. The dependence of HBV replication on host cell machineries and their co-evolutionary interactions prompt the codon usage pattern of viral genes to translation selection and mutation pressure. Objective The evolutionary characteristics of HBV and the natural selection effects of the human genome on the codon usage characteristics were analyzed to provide a basis for medication development for HBV infection. Methods The codon usage pattern of sequences from different HBV genotypes of our isolates and reference HBV genome sequences downloaded from the National Center for Biotechnology Information (NCBI) database were analyzed by computing the relative synonymous codon usage (RSCU), nucleotide content, codon adaptation index (CAI) and the effective number of codons (ENC). Results The highest ENC values were observed in the C genotypes, followed by the B genotypes. The ENC values indicated a weak codon usage bias (CUB) in HBV genome. The number of codons differentially used between the three genotypes was markedly higher than that of similarly used codons. High CAI values indicated a good adaptability of HBV to its host. The ENC plot indicated the occurrence of mutational pressure in the three genotypes. The mean Ka/Ks ratios in the three genotypes were lower than 1, which indicated a negative selection pressure. The CAI and GC3% plot indicated the existence of CUB in the HBV genome. Conclusions Nucleotide composition, mutation bias, negative selection and mutational pressure are key factors influencing the CUB and phylogenetic diversity in HBV genotypes. The data provided here could be useful for developing drugs for HBV infection.

Microstructural Refinement and Performance Improvement of Cast n-Type Bi2Te2.79Se0.21 Ingot by Equal Channel Angular Extrusion

Xiaoming Hu,Xi’an Fan,Bo Feng,Dong Kong,Peihai Liu,Rusong Li,Yanglin Zhang,Guangqiang Li,Yawei Li 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.8

How to form a uniform fine-grained structure in n-type polycrystalline Bi2Te3based alloys to stabilize and improve thethermoelectric properties is the burning issue to be solved. In the present work, equal channel angular extrusion (ECAE)method was used to extrude the cast ingot directly at various temperatures to obtain the BiTeSe polycrystalline bulk alloyswith uniform microstructure. The initial lamellae coarse grains (hundreds microns to several millimeters) were efficiently anduniformly refined to a minimum of 4.07 μm at 703 K, which fully demonstrates the feasibility of grain refinement by ECAEfor cast n-type BiTeSe ingot. The average grain size of the extruded billets rapidly increased from 5.35 to 29.55 μm withthe increase of extrusion temperature from 703 to 823 K. Meanwhile, the behavior of abnormal grain growth became moreevident as the extrusion temperature increased because the growth rate increased more rapidly than the rate of nucleation. As the extrusion temperature increased, the Vickers hardness decreased gradually due to grain coarsening. BiTeSe alloysextruded at 703 K achieved the maximum Vickers hardness of 59.8 HV0.05,which was nearly three times higher than that ofthe initial cast ingot. All extruded BiTeSe billets possessed the much higher dimensionless figure of merit (ZT), comparedwith the initial cast ingot due to the simultaneously optimization of electrical and thermal transport performances caused byECAE process. Finally, the specimen extruded at 823 K achieved the maximum ZT of 0.685 at 383 K.

Coronary Flow Reserve in Non-Infarcted Myocardium Predicts Long-Term Clinical Outcomes in Patients Undergoing Percutaneous Coronary Intervention

Rongchao Cheng,Xiaoming Zhu,Yunling Li,Xiuping Bai,Li Xue,Li Wei 연세대학교의과대학 2018 Yonsei medical journal Vol.59 No.2

Purpose: Coronary flow reserve (CFR) is recognized as an indicator of myocardial perfusion. The aim of this study was to assess the relationship between CFR in the non-infarcted myocardium and the incidence of major adverse cardiac events (MACEs). Materials and Methods: 100 consecutive patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention(PCI) were enrolled in the present study, and divided into MACE and non-MACE groups according to the incidence of 12-month MACEs. Left ventricular function and CFR were analyzed using two-dimensional echocardiography and myocardial contrast echocardiography at one week after PCI. Cardiac troponin I levels were assayed to estimate peak concentrations thereof. Results: The MACE group was associated with lower CFR, compared to the non-MACE group (2.41 vs. 2.77, p<0.001). In the multivariablemodel, CFR in the non-infarcted myocardium was an independent predictor of 12-month MACE (hazard ratio: 0.093, 95% confidence interval: 0.020–0.426, p=0.002) after adjustment for baseline demographic and clinical characteristics. Conclusion: CFR in the non-infarcted myocardium is a useful marker for predicting 12-month MACEs in patients with AMI undergoingprimary PCI.

Highly Sensitive Detection of Low-Abundance White Spot Syndrome Virus by a Pre-Amplification PCR Method

( Xiaoming Pan ),( Yanfang Zhang ),( Xuejiao Sha ),( Jing Wang ),( Jing Li ),( Ping Dong ),( Xingguo Liang ) 한국미생물 · 생명공학회 2017 Journal of microbiology and biotechnology Vol.27 No.3

White spot syndrome virus (WSSV) is a major threat to the shrimp farming industry and so far there is no effective therapy for it, and thus early diagnostic of WSSV is of great importance. However, at the early stage of infection, the extremely low-abundance of WSSV DNA challenges the detection sensitivity and accuracy of PCR. To effectively detect low-abundance WSSV, here we developed a pre-amplification PCR (pre-amp PCR) method to amplify trace amounts of WSSV DNA from massive background genomic DNA. Combining with normal specific PCR, 10 copies of target WSSV genes were detected from ~10¹⁰ magnitude of backgrounds. In particular, multiple target genes were able to be balanced amplified with similar efficiency due to the usage of the universal primer. The efficiency of the pre-amp PCR was validated by nested-PCR and quantitative PCR, and pre-amp PCR showed higher efficiency than nested-PCR when multiple targets were detected. The developed method is particularly suitable for the super early diagnosis of WSSV, and has potential to be applied in other low-abundance sample detection cases.

LAOSHAN ORCHARD + LAOSHAN MINERAL WATER

Li ying,Yang ying,Sun xiaoming 한국청소년시설환경학회 2012 한국청소년시설환경학회 학술대회 Vol.2012 No.1

Preliminary numerical study of single bubble dynamics in swirl flow using volume of fluid method

Li, Zhongchun,Qiu, Zhifang,Du, Sijia,Ding, Shuhua,Bao, Hui,Song, Xiaoming,Deng, Jian Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.4

Spacer grid with mixing vane had been widely used in nuclear reactor core. One of the main feather of spacer grid with mixing vane was that strong swirl flow was formed after the spacer grid. The swirl flow not only changed the bubble generation in the near wall field, but also affected the bubble behaviors in the center region of the subchannel. The interaction between bubble and the swirl flow was one of the basic phenomena for the two phase flow modeling in fuel assembly. To obatin better understanding on the bubble behaviors in swirl flow, full three dimension numerical simulations were conducted in the present paper. The swirl flow was assumed in the cylindral calculation domain. The bubble interface was captured by Volume Of Fluid (VOF) method. The properties of saturated water and steam at different pressure were applied in the simulation. The bubble trajectory, motion, shape and force were obtained based on the bubble parameters captured by VOF. The simulation cases in the present study included single bubble with different size, at different angular velocity conditions and at different pressure conditions. The results indicated that bubble migrated to the center in swirl flow with spiral motion type. The lateral migration was mainly related to shear stress magnitude and bubble size. The bubble moved toward the center with high velocity when the swirl magnitude was high. The largest bubble had the highest lateral migration velocity in the present study range. The effect of pressure was small when bubble size was the same. The prelimenery simulation result would be beneficial for better understanding complex two phase flow phenomena in fuel assembly with spacer grid.