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Determination of Lead in Lime-preserved Egg by Microwave Digestion and Flame Atomic Absorption Spectroscopy

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Asian Agricultural Research 2023年第7期15卷 51-53页

作者： Mimi ZHANG Anhui Institute for Food and Drug Control Hefei 230051China national Agriculture vice-processing Food Surveillance test center Hefei 230051China

[Objectives] To establish a method for determining the lead content in lime-preserved eggs, to provide a theoretical basis for the quality control of production enterprises and the sampling and testing of supervision departments. [Methods] The lead content in lime-preserved eggs was measured by the microwave digestion and flame atomic absorption spectroscopy. [Results] The method had a correlation coefficient of r2=0.998 in the injection concentration range of 0-4 mg/L. The detection limit of the method was 0.008 2 mg/kg. In the range of 0.2 to 1.0 mg/kg addition concentration, the recovery rate of the method was 92.5%-108.0%, and the relative standard deviation(RSD) was <5%. [Conclusions] This method is accurate and reliable, simple and efficient, and is suitable for the detection of lead in lime-preserved eggs.

关键词： Microwave Digestion Flame atomic absorption spectroscopy Lime-preserved eggs Lead

Geographical classification of Nanfeng mandarin by near infrared spectroscopy coupled with chemometrics methods

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Journal of Innovative Optical Health Sciences 2014年第6期7卷 70-76页

作者： Xuan Zhang Yiping Du Peijin Tong Yuanlong Wei Man Wang Shanghai Key Laboratory of Functional Materials Chemistry and Research center of Analysis and test East China University of Science and Technology Meilong Rd 130 ShanghaiP.R.China 200237 Comprehensive Technology center of Jiangxi Entry-Exit Inspection and Quarantine Bureau and Jiangxi Province Engineering Research center of Infrared Spectroscopy Application South Gan River Avenue 2666 Nanchang Jiangxi ProvinceP.R.China 330038

Near infrared spectroscopy(NIRS),coupled with principal component analysis and wavelength selection techniques,has been sed to develop a robust and reliable reduced-spectrum classifi-cation model for determining the geographical origins of Nanfeng *** application of the changeable size moving window principal component analysis(CSMWPCA)provided a notably improved lassification model,with correct classification rates of 92.00%,100.00%,90.00%,100.00%,100.00%,100.00%and 100.00%for Fujian,Guangxi,Hunan,Baishe,Baofeng,Qiawan,Sanxi samples,respectively,as well as,a total dassification rate of 97.52%in the wavelength range from 1007 to 1296 *** test and apply the proposed method,the procedure was applied to the analysis of 59 samples in an independent test *** identification results(correct rate of 96.61%)were also *** improvement achieved by the application of CSMWPCA method was particularly remarkable when taking the low complexities of the final model(290 variables)into *** results of the study showed the great potential of NIRS as a fast,nondestructive and environmentally acceptable method for the rapid and reliable determination for geographical classifcation of Nanfeng mandarins.

关键词： Near infrared spectroscopy Nanfeng mandarin geographical origin changeable size moving window principal component analysis,variable selection

Determination of primary aromatic amines using immobilized nanoparticles based surface-enhanced Raman spectroscopy

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Chinese Chemical Letters 2016年第5期27卷 745-748页

作者： Ting Wu Hai-Ting Wang Bo Shen Yi-Ping Du Xuan Wang Zhen-Ping Wang Chuan-Jing Zhang Wen-Bin Miu Shanghai Key Laboratory of Functional Materials Chemistry and Research Centre of Analysis and TestEast China University of Science and TechnologyShanghai 200237China Technical center for Industrial Products and Raw Materials Inspection and testing Shanghai Entry-Exit Inspection&Inspection and Quarantine Bureau Shanghai 200135China

Primary aromatic amines （PAAs） are substances with toxicity and suspected human carcinogenicity. A facile method for highly sensitive detection of PAAs using surface-enhanced Raman spectroscopy （SERS） is reported. The immobilization of Au nanoparticles （AuNPs） on the glycidyl methacrylate-ethylene dimethacrylate （GMA-EDMA） materials makes the suhstrate a closely packed but not aggregated Au NP arrays which provides a prominent SERS enhancement. Four PAAs with different substituent groups, namely, p-toluidine, p-nitroaniline, benzidine and 4,4-methylene-bis-（2-chloroaniline） have been successfully identified and quantified. High sensitivity and good linear relationship between SERS signals and concentrations of PAAs are obtained for all four PAAs.

关键词： Aromatic amines Surface-enhanced Raman spectroscopy(SERS) Immobilization Au nanoparticles

UV-induced Self-initiated Graft Polymerization of Acrylamide onto Poly(ether ether ketone)

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Chemical Research in Chinese Universities 2012年第1期28卷 162-165页

作者： CHEN Rui-chao, SUN Hui, LI Ang and XU Guo-zhi College of Materials Science and Mechanical Engineering, national center for quality supervision and test of Plastic Products, Beijing Technology and Business University, Beijing 100048, P. R. China Beijing Technol & Business Univ Coll Mat Sci & Mech Engn Natl Ctr Qual Supervis & Test Plast Prod Beijing 100048 Peoples R China

Photo-grafting of hydrophilic monomer was used to enhance the hydrophilicity of poly（ether ether ketone）（PEEK） with the aim of extending its applications to biological fields. PEEK sheets were surface modified by grafting of acrylamide（AAm） with ultraviolet（UV） irradiation in the presence or absence of benzophenone（BP）. The effects of BP, irradiation time and monomer concentration on the surface wettability of PEEK were investigated. Characteriza tion of modified PEEK using scanning electron microscopy（SEM）, energy-disperse spectrometer（EDS） and water contact angle measurements shows that AAm was successfully grafted on PEEK surface both in presence and absence of BP. With the increase in irradiation time and monomer concentration, contact angles decrease to as low as 30°, demonstrating a significant improvement of surface hydrophilicity. In agreement with the decrease in contact angle, under identical conditions, the nitrogen concentration increases, suggesting the increase in grafting degree of the grafting polymerization. This investigation demonstrates a self-initiation of PEEK due to its BP-like structure in the backbone of the polymer. Though the graft polymerization proceeds more readily in the presence of BP, the self-initiated graft polymerization is clearly observed.

关键词： Poly(ether ether ketone)(PEEK) UV-grafting Surface modification Self-initiation Graft polymerization

Estimation of the population,death,and quality of life in Shaanxi Province,western China:a cross-sectional study

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Chinese Medical Journal 2023年第15期136卷 1832-1838页

作者： Xinlei Miao Jun Chen Qiong Wu Wen Meng Lin Ren Zhiyuan Wu Xiuhua Guo Xiang Zhang Qun Meng School of Public Health Capital Medical UniversityBeijing 100069China Health Management center the Second Hospital of Dalian Medical UniversityDalianLiaoning 116023China center of Information Statistics Health Information Center of Shaanxi ProvinceXi’anShaanxi 710003China center of Information Statistics National Health Commission of the People’s Republic of ChinaBeijing 100044China Department of Infection Prevention&Control Peking University People’s HospitalBeijing 100044China Information Management center Affiliated Zhongshan Hospital of Dalian UniversityLiaoning 116001China Comprehensive supervision Bureau National Health Commission of the People’s Republic of ChinaBeijing 100044China

Background:Measuring the health of the population is of great significance to the development of a *** aimed to estimate the population,probability of death,and quality of life in western ***:We calculated the age-specific mortality rate and prevalence rate of diseases and injuries using the Full Population Database and the Home Page of Inpatient Medical *** used multiple interpolation methods to insert missing information from the death data and the model of Kannisto to adjust the mortality rate for elderly *** age-specific prevalence rate of diseases and injuries was adjusted according to the standard ratio of age and methods of equal proportional *** expectancy was calculated by a life table,and the quality of life was estimated using the Sullivan ***:The total population continued to increase in 2015 to 2019 in the Shaanxi Province,*** mortality rate of children under five has improved,and the mortality rate of people over 65 is decreasing year by *** expectancy increased from 74.66 years in 2015 to 77.19 years in *** with the total risk of disease and injury,the health-adjusted life expectancy increased by 1.90 years within 5 years,and the number of unhealthy years significantly ***-adjusted life expectancy increased by 1.75 years when only considered the ten major disease systems(tumors;endocrinology,nutrition and metabolism;mental and behavioral disorders;nervous system;sensory diseases;circulatory system;respiratory system;digestive system;genitourinary system;musculoskeletal system and connective tissue),and the number of unhealthy years increased ***:In the past five years,Shaanxi Province has made progress in improving life expectancy and controlling the development of chronic *** is necessary to take specific preventive measures and improve the quality of basic public health services.

关键词： China Chronic disease Life expectancy Mortality rate quality of life

Development and Challenge of HIV/AIDS testing Laboratory Network and quality Assurance System in China

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Virologica Sinica 2007年第6期22卷 434-442页

作者： Yan JIANG national AIDS Reference Laboratory of national center for AIDS/STD Control and Prevention Chinese Center for Disease Control and Prevention Beijing 100050 China

This paper describes the development and challenge of HIV/AIDS testing laboratory network and quality assurance system in China. At present,the HIV/AIDS testing laboratories includes three classes,the national AIDS Reference Laboratory,HIV/AIDS confirmatory laboratories and HIV/AIDS screening laboratories. All of them are accredited by the health authorities,and each class of laboratories take charge of their function strictly according to the "national Management of HIV/AIDS Detection (2006)". A complete quality assurance and quality control system for HIV/AIDS testing has been developed,which includes technical training,strict laboratory monitoring and approval,examination or proficiency testing on HIV/AIDS detection,and quality evaluation and supervision of HIV/AIDS diagnostic kits. Besides conduct the routine anti-HIV antibody test,more and more laboratories began to conduct other tests,such as CD4+ T lymphocyte cell counting,HIV viral load,HIV DNA PCR,genotyping,drug resistance,and HIV-1 recent infection test. The primary challenges faced by the HIV/AIDS testing laboratory network are in the areas of laboratory management and quality control. For example,the provincial PT program is inefficient,the internal quality control is conducted perfunctorily,personnel training can not met the needs of the workplace,which need to be improved.

关键词： Human immunodeficiency virus (HIV) Laboratory Detection quality assurance quality control

A review and evaluation of nonroad diesel mobile machinery emission control in China

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Journal of Environmental Sciences 2023年第1期123卷 30-40页

作者： Pengju Bie Liang Ji Huanxing Cui Gang Li Shunli Liu Ying Yuan Kebin He Huan Liu State Key Joint Laboratory of ESPC State Environmental Protection Key Laboratory of Sources and Control of Air Pollution ComplexSchool of EnvironmentInternational Joint Laboratory on Low Carbon Clean Energy InnovationTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation Chinese Research Academy of Environmental SciencesBeijing 100012China Jinan automobile testing center Co Ltd.Jinan 250102China

China’s emission control for nonroad diesel mobile machinery(NDMM)must deal with a fast increase in stock as well as regulations that are two decades behind those for on-road *** study provides the first large-scale review and evaluation of China’s NDMM policies,along with emission measurements and an investigation on diesel fuel *** sulfur contents of the investigated diesel declined from 430 ppm(median value)in 2011 to6-8 ppm during the 2017-2018 *** emission control of NO_(x)and PM greatly improved with the shift from the China II to China IV standards,as demonstrated by engine tests and field NO_(x)***,the NO_(x)emission factors for non-type-approved engines were approximately twice the limits of the China II *** compliance based on bench tests was not sufficient to control actual emissions because the field-measured NO_(x)emission factors of all machinery ranged from 24%to 225%greater than the respective emission limits for the *** circumstances adversely affected the effectiveness of the regulations and policies for China’s emission control of ***,the policies on new and in-use NDMM,as well as diesel fuel quality,prevented NO_(x)and PM emissions amounting to 4.4 Tg and 297.8 Gg during the period 2008-2017,*** emission management strategy contributed to enhancing the international competitiveness of China’s NDMM industries by promoting advanced *** effective NDMM emission control in the future,portable testing and noncontact remote supervision should be strengthened;also,the issue of noncompliant diesel should be addressed through rigorous control measures and financial penalties.

关键词： Nonroad mobile machinery Emission reduction Emission control policy Emission factor Diesel fuel quality

Performance evaluation of the use of tire-derived fuel fly ash as mineral filler in hot mix asphalt concrete

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第2期7卷 249-258页

作者： Min Ju Choi Yong Joo Kim Hyeok Jung Kim Jae Jun Lee BILTZONE Co. Ltd.Hwaseong 18514South Korea Korea Institute o f Civil Engineering and Building Technology Goyang-Si 10223South Korea Industry-Academic Cooperation Foundation center Hankyong National UniversityAnseong-si 17579South Korea Department of Civil Engineering Chonbuk National UniversityJeonju 54896South Korea

According to deplete natural resources and need to protect the environment,the demand of a usage of waste material has significantly *** studies are currently being carried out on the development of innovative and environmentally friendly materials for securing the safety of road users and improving the performance and durability of *** example,studies are currently being conducted on the use of waste tires as a substitute for currently used *** the development of the automobile industry,the amount of waste tire has continuously increased in accordance with the increased vehicle ***-derived fuel(TDF)has been used as a fuel source with generated TDF fly *** filler,made of fine mineral particles of a physical size passing the number 200 standard mesh sieve(75 micron),plays an important role in asphalt mixtures *** paper presents an application of TDF fly ash as filler in hot mix asphalt(HMA).In this study,the performance of TDF fly ash was confirmed through a comparison with three other mineral fillers:stone dust,cement,and hydrated *** tests including Marshall stability test,moisture sensitivity test,dynamic immersion test,and a wheel tracking test were performed to investigate the difference in the behaviors of the samples with different parameters considered in this *** results show that the mechanical performance of hot mix asphalt using TDF fly ash satisfied the quality standard specification of the Ministry of Land,Infrastructure and Transport(MOLIT),*** can be concluded that the use of TDF fly ash as a mineral filler in HMA not only satisfied the mechanical properties,but also reduced the volume of the pollutants waste in the environment.

关键词： Asphalt mixture TDF fly ash Marshal stability Moisture sensitive TSR

Breeding and Application of Guidan 903,a New High-yield and Good-quality Maize Variety

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Agricultural Biotechnology 2021年第5期10卷 45-48页

作者： Jinguo ZHOU Xiaodong XIE Haiyu ZHOU Yufeng JIANG Lanqiu QIN Hexia XIE Zhaolei TANG Weidong CHENG Maize Research Institute Guangxi Academy of Agricultural Sciences/Guangxi Sub-centerNational Maize Improvement CenterNanning 530007China

To meet the demand of maize production in Guangxi and even the southwest region of China and realize the upgrading and undating of maize varieties which will continuously improve the yield and quality of maize,a new big-ear maize variety Guidan 903 with high yield,stable yield and good quality was established by the Maize Research Institute of Guangxi Academy of Agricultural Sciences with two self-selected inbred line GRL17349 and GRL21191 as female and male parents *** average yield of this variety were 7429.5 and 7000.5 kg/hm^(2)in Guangxi Maize Regional Trial and Production test respectively,which increased by 6.3%and 5.6%than the control(Guidan162).It was approved by Guangxi Zhuang Autonomous Region Crop Variety Certification Committee in June 2020(Approval *** sheng yu 2020083).Determined by the Cereal quality supervision and testing center of Ministry of Agriculture and Rural Affairs(Bejjing),the grain bulk density,ratio of crude protein,crude fat,crude starch and lysine of Guidan 903 were 782 g/L,9.41%,6.19%,71.45%,0.35%*** variety has the characterisics of strong resistance to collapse and disease,good quality,high and stable yield and wide ***,its seed yield is high with easy production technology and low cost.

关键词： Maize New variety Guidan 903 Breeding Seed production technology Cultivation