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DNA Contamination and Treatment Countermeasures in Dog DNA Testing Laboratory
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作者 Wei Rongxing Ye Junhua 《Animal Husbandry and Feed Science》 CAS 2017年第6期352-354,共3页
DNA contamination will directly result in wrong conclusion of DNA test. The higher the detection accuracy is, the greater the harmful of contamination is. DNA contamination can be divided into sample contamination and... DNA contamination will directly result in wrong conclusion of DNA test. The higher the detection accuracy is, the greater the harmful of contamination is. DNA contamination can be divided into sample contamination and PCR contamination. It is the most difficult to treat and prevent aerosol contamination of PCR. In order to prevent pollution, dog DNA testing laboratory should be divided into several independent areas, and the researchers should strictly obey the operation rules. In addition, we should design control experiment scientifically to track pollution sources and eliminate the contamination through technical means, once the pollution occurs. 展开更多
关键词 Dog DNA laboratory Highly sensitive DNA kit PCR contamination Aerosol contamination
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Factors Contributing to Contamination of Street Foods in Bamako, Mali
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作者 Demba Dembele Mamadou Wele +4 位作者 Bawa Boya Haziz Sina Basile Boni Saka Konmy Adolphe Adjanohoun Lamine Baba-Moussa 《Food and Nutrition Sciences》 CAS 2024年第3期199-210,共12页
The World Health Organization states that foodborne diseases are a worldwide public health issue. Although street foods can provide nutritious and affordable ready-to-eat meals for city dwellers, their health risks ca... The World Health Organization states that foodborne diseases are a worldwide public health issue. Although street foods can provide nutritious and affordable ready-to-eat meals for city dwellers, their health risks can outweigh the benefits. A cross-sectional study was conducted in the Bamako district, focusing on street food vendors near schools, universities, extensive markets, administrative centers, and major roads. We aimed to sample fifty (50) sellers per municipality, making 300 sellers for the Bamako district. We developed a survey sheet to collect data, and six teams rotated between the municipalities each month. Before starting the collection, the teams were provided administrative papers approved by the municipal authority. The survey revealed three types of sales sites: fixed (65%), semi-fixed (30%), and mobile (4.40%). The proportion of sellers was 26.8%, 23.2%, 19.7%, and 4.2% in municipalities III, IV, and I. In municipalities I, II, III, IV, and VI, respectively, 92%, 95.70%, 93%, 87.2%, and 100% of the sellers were female. The age distribution of sellers was 65.63%, 46.81%, 40.82%, 38.30%, 36.17%, 36%, and 32% in the 25-34 and 35 - 44 age groups. Illiteracy rates were 59.20%, 61.70%, 55.30%, 75%, and 56% in municipalities I, II, III, IV, and VI, respectively. The study identified two categories of sellers: 48.3% in type 1 and 51.7% in type 2. The first category comprised 154 sellers, and the second 165 sellers. The survey found that 66.00%, 56.00%, 48.90%, 44.90%, 38.30%, and 34.40% of municipal V, VI, III, I, II, and IV sales sites were open-air. In municipality I, 63.30% of the sites were under hangars, while in municipalities II and IV, the corresponding percentages were 51.10% and 59.40%, respectively. Moreover, 46.00%, 31.90%, 31.30%, 30.60%, and 27.70% of the sites in municipalities VI, II, IV, I, and III were located next to gutters. In conclusion, this study identified several factors that could compromise the quality of street foods sold in the six municipalities of Bamako. 展开更多
关键词 FACTORS SOURCE contamination Street Food BAMAKO
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Phytoremediation Strategies for Heavy Metal Contamination: A Review on Sustainable Approach for Environmental Restoration
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作者 Mariam Salifu Matthew Abu John +3 位作者 Murtala Abubakar Ibukunoluwa Abimbola Bankole Nneka Damola Ajayi Olawumi Amusan 《Journal of Environmental Protection》 2024年第4期450-474,共25页
Current globalization trends and important breakthroughs globally need a complete study of heavy metal contamination, its causes, its impacts on human and environmental health, and different remediation strategies. He... Current globalization trends and important breakthroughs globally need a complete study of heavy metal contamination, its causes, its impacts on human and environmental health, and different remediation strategies. Heavy metal pollution is mostly produced by urbanization and industry, which threatens ecosystems and human health. Herein, we discuss a sustainable environmental restoration strategy employing phytoremediation for heavy metal pollution, the carcinogenic, mutagenic, and cytotoxic effects of heavy metals such as cadmium, copper, mercury, selenium, zinc, arsenic, chromium, lead, nickel, and silver, which may be fatal. Phytoremediation, which was prioritized, uses plants to remove, accumulate, and depollute pollutants. This eco-friendly method may safely collect, accumulate, and detoxify toxins using plants, making it popular. This study covers phytostabilization, phytodegradation, rhizodegradation, phytoextraction, phytovolatilization, and rhizofiltration. A phytoremediation process’s efficiency in varied environmental circumstances depends on these components’ complex interplay. This paper also introduces developing phytoremediation approaches including microbe-assisted, chemical-assisted, and organic or bio-char use. These advancements attempt to overcome conventional phytoremediation’s limitations, such as limited suitable plant species, location problems, and sluggish remediation. Current research includes machine learning techniques and computer modeling, biostimulation, genetic engineering, bioaugmentation, and hybrid remediation. These front-line solutions show that phytoremediation research is developing towards transdisciplinary efficiency enhancement. We acknowledge phytoremediation’s promise but also its drawbacks, such as site-specific variables, biomass buildup, and sluggish remediation, as well as ongoing research to address them. In conclusion, heavy metal pollution threatens the ecology and public health and must be reduced. Phytoremediation treats heavy metal pollution in different ways. Over time, phytoremediation systems have developed unique ways that improve efficiency. Despite difficulties like site-specificity, sluggish remediation, and biomass buildup potential, phytoremediation is still a vital tool for environmental sustainability. 展开更多
关键词 PHYTOREMEDIATION HEAVY-METAL contamination SUSTAINABILITY RESTORATION
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Classification of Cybersecurity Threats, Vulnerabilities and Countermeasures in Database Systems
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作者 Mohammed Amin Almaiah Leen Mohammad Saqr +3 位作者 Leen Ahmad Al-Rawwash Layan Ahmed Altellawi Romel Al-Ali Omar Almomani 《Computers, Materials & Continua》 SCIE EI 2024年第11期3189-3220,共32页
Database systems have consistently been prime targets for cyber-attacks and threats due to the critical nature of the data they store.Despite the increasing reliance on database management systems,this field continues... Database systems have consistently been prime targets for cyber-attacks and threats due to the critical nature of the data they store.Despite the increasing reliance on database management systems,this field continues to face numerous cyber-attacks.Database management systems serve as the foundation of any information system or application.Any cyber-attack can result in significant damage to the database system and loss of sensitive data.Consequently,cyber risk classifications and assessments play a crucial role in risk management and establish an essential framework for identifying and responding to cyber threats.Risk assessment aids in understanding the impact of cyber threats and developing appropriate security controls to mitigate risks.The primary objective of this study is to conduct a comprehensive analysis of cyber risks in database management systems,including classifying threats,vulnerabilities,impacts,and countermeasures.This classification helps to identify suitable security controls to mitigate cyber risks for each type of threat.Additionally,this research aims to explore technical countermeasures to protect database systems from cyber threats.This study employs the content analysis method to collect,analyze,and classify data in terms of types of threats,vulnerabilities,and countermeasures.The results indicate that SQL injection attacks and Denial of Service(DoS)attacks were the most prevalent technical threats in database systems,each accounting for 9%of incidents.Vulnerable audit trails,intrusion attempts,and ransomware attacks were classified as the second level of technical threats in database systems,comprising 7%and 5%of incidents,respectively.Furthermore,the findings reveal that insider threats were the most common non-technical threats in database systems,accounting for 5%of incidents.Moreover,the results indicate that weak authentication,unpatched databases,weak audit trails,and multiple usage of an account were the most common technical vulnerabilities in database systems,each accounting for 9%of vulnerabilities.Additionally,software bugs,insecure coding practices,weak security controls,insecure networks,password misuse,weak encryption practices,and weak data masking were classified as the second level of security vulnerabilities in database systems,each accounting for 4%of vulnerabilities.The findings from this work can assist organizations in understanding the types of cyber threats and developing robust strategies against cyber-attacks. 展开更多
关键词 Cyber threats database systems cyber risk assessment VULNERABILITIES countermeasures
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Long-term hydrochemical monitoring and geothermometry:understanding groundwater salinization and thermal fluid contamination in Mila’s basin,Northeastern Algeria
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作者 Yasmina Bouroubi-Ouadfel Adnane Souffi Moulla Abdelkader Khiari 《Acta Geochimica》 EI CAS CSCD 2024年第3期459-477,共19页
The regular hydrochemical monitoring of groundwater in the Mila basin over an extended period has provided valuable insights into the origin of dissolved salts and the hydrogeochemical processes controlling water sali... The regular hydrochemical monitoring of groundwater in the Mila basin over an extended period has provided valuable insights into the origin of dissolved salts and the hydrogeochemical processes controlling water salinization.The data reveals that the shallow Karst aquifer shows an increase in TDS of 162 mg L^(-1) while the ther-mal carbonate aquifer that is also used for drinking water supply exhibits an increase of 178 mg L^(-1).Additionally,significant temperature variations are recorded at the sur-face in the shallow aquifers and the waters are carbo-gaseous.Analysis of dissolved major and minor elements has identified several processes influencing the chemical composition namely:dissolution of evaporitic minerals,reduction of sulphates,congruent and incongruent car-bonates’dissolution,dedolomitization and silicates’weathering.The hydrogeochemical and geothermometric results show a mixing of saline thermal water with recharge water of meteoric origin.Two main geothermalfields have been identified,a partially evolved water reservoir and a water reservoir whosefluid interacts with sulphuric acid(H_(2)S)of magmatic origin.These hot waters that are char-acterized by a strong hydrothermal alteration do ascend through faults and fractures and contribute to the contamination of shallower aquifers.Understanding the geothermometry and the hydrogeochemistry of waters is crucial for managing and protecting the quality of groundwater resources in the Mila basin,in order to ensure sustainable water supply for the region.A conceptual model for groundwater circulation and mineralization acquisition has been established to further enhance under-standing in this regard. 展开更多
关键词 Hydrochemical monitoring HYDROGEOCHEMISTRY SALINIZATION Geothermal reservoir contamination Mila’s basin
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Investigation of an electrode-driven hydrogen plasma method for in situ cleaning of tin-based contamination
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作者 彭怡超 叶宗标 +7 位作者 王思蜀 蒲国 刘显洋 苑聪聪 廖加术 韦建军 余新刚 芶富均 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第8期73-83,共11页
To prolong the service life of optics,the feasibility of in situ cleaning of the multilayer mirror(MLM)of tin and its oxidized contamination was investigated using hydrogen plasma at different power levels.Granular ti... To prolong the service life of optics,the feasibility of in situ cleaning of the multilayer mirror(MLM)of tin and its oxidized contamination was investigated using hydrogen plasma at different power levels.Granular tin-based contamination consisting of micro-and macroparticles was deposited on silicon via physical vapor deposition(PVD).The electrodedriven hydrogen plasma at different power levels was systematically diagnosed using a Langmuir probe and a retarding field ion energy analyzer(RFEA).Moreover,the magnitude of the self-biasing voltage was measured at different power levels,and the peak ion energy was corrected for the difference between the RFEA measurements and the self-biasing voltage(E_(RFEA)-eV_(self)).XPS analysis of O 1s and Sn 3d peaks demonstrated the chemical reduction process after 1 W cleaning.Analysis of surface and cross-section morphology revealed that holes emerged on the upper part of the macroparticles while its bottom remained smooth.Hills and folds appeared on the upper part of the microparticles,confirming the top-down cleaning mode with hydrogen plasma.This study provides an in situ electrode-driven hydrogen plasma etching process for tin-based contamination and will provide meaningful guidance for understanding the chemical mechanism of reduction and etching. 展开更多
关键词 tin-based contamination hydrogen plasma in situ cleaning ion energy
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Assessment of Heavy Metals Contamination of Topsoil and Street Dust around Cement Factory in Southern Jordan
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作者 Omar Ali Al-Khashman Alia Omar Al-Khashman +2 位作者 Navasingh Rajesh Jesudoss Hynes Hani M. Alnawafleh Pitchumani Shenbaga Velu 《Journal of Environmental Protection》 2024年第6期672-696,共25页
Evaluation of assessment of the metal processes governing the metals distribution in soil and dust samples is very significant and protects the health of human and ecological system. Recently, special attention has gi... Evaluation of assessment of the metal processes governing the metals distribution in soil and dust samples is very significant and protects the health of human and ecological system. Recently, special attention has given to the assessment of metals pollution impact on soil and dust within industrial areas. This study aims to assess the metal contamination levels in the topsoil and street dust around the cement factory in Qadissiya area, southern Jordan. The levels of seven metals (namely Fe, Zn, Cu, Pb, Cr, Cd, and Mn) were analyzed using Flame Atomic Absorption Spec-trophotometer (FAAS) to monitor, evaluate, and to compare topsoil and road dust pollution values of metals of the different types of urban area. The physicochemical parameters which believed to affect the mobility of metals in the soil of the study area were determined such as pH, EC, TOM, CaCO3 and CEC. The levels of metal in soil samples are greater on the surface but decrease in the lower part as a result of the basic nature of soil. The mean values of the metals in soil can be arranged in the following order: Zn > Pb > Mn > Fe > Cu > Cr > Cd. The relatively high concentration of metals in the soil sample was attributed to anthropogenic activities such as traffic emissions, cement factory and agricultural activities. Correlation coefficient analysis and the spatial distribution of indices and the results of statistical analysis indicate three groups of metals: Fe and Mn result by natural origin, Zn, Pb, Cu and Zn result by anthropogenic origin (mainly motor vehicle traffic and abrasion of tires) while Cd is mixed origin. The higher content level values of metals of anthropogenic source in soil samples indicate that it is a source of contamination of air in the studied area. . 展开更多
关键词 Cement Dust Heavy Metals contamination Risk Assessment Statistical Analysis JORDAN
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Evaluating bacterial contamination and surgical site infection risks in intracorporeal anastomosis: Role of bowel preparation
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作者 Junho Lee 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1953-1955,共3页
We recently read the study by Kayano et al on intracorporeal anastomosis(IA)for colon cancer,which assessed bacterial contamination and medium-term onco-logical outcomes and affirmed that IA is analogous to extracorpo... We recently read the study by Kayano et al on intracorporeal anastomosis(IA)for colon cancer,which assessed bacterial contamination and medium-term onco-logical outcomes and affirmed that IA is analogous to extracorporeal anastomosis in reducing intraperitoneal bacterial risk and achieving similar oncological results.Our commentary addresses gaps,particularly concerning bowel preparation and surgical site infections(SSIs),and highlights the need for comprehensive details on the bowel preparation methods that are currently employed,including mecha-nical bowel preparation,oral antibiotics(OA),their combination,and specific OA types.We emphasize the necessity for further analyses that investigate these me-thods and their correlation with SSI rates,to enhance clinical protocol guidance and optimize surgical outcomes.Such meticulous analyses are essential for refi-ning strategies to effectively mitigate SSI risk in colorectal surgeries. 展开更多
关键词 Intracorporeal anastomosis Surgical site infection Mechanical bowel preparation Oral antibiotics Bacterial contamination Colon cancer
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Current Situation and Countermeasures of Household Waste Classification in Feixi County, Hefei City
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作者 Yaqi XU Yalong JIANG +2 位作者 Enqing GAO Shimao FENG Yuchen QIANG 《Meteorological and Environmental Research》 2024年第3期77-81,共5页
Feixi County has made significant progress in promoting waste classification,such as establishing a comprehensive classification system,and effectively reducing environmental pollution and waste volume.However,with th... Feixi County has made significant progress in promoting waste classification,such as establishing a comprehensive classification system,and effectively reducing environmental pollution and waste volume.However,with the increase in waste generation,the county faces multiple challenges especially in the disposal of kitchen waste and improvement of residents environmental awareness.To address these issues,Feixi County has implemented various measures,such as strengthening the construction of infrastructure for waste classification,improving regulations and clearly defining responsibilities,enhancing residents environmental awareness to encourage their participation in waste classification through education and promotion,and increasing supervision to ensure effective implementation of the work.It emphasizes community governance,encourage all parties to participate in it,and strengthen publicity,education and training to enhance residents participation.Feixi County has achieved positive results,but efforts are needed to further improve facilities,raise awareness,enhance supervision,and ensure the continuous effectiveness of waste classification work to promote urban green sustainable development. 展开更多
关键词 Household waste classification Current situation countermeasures Feixi County
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Opportunities, Challenges, and Countermeasures of China Myanmar Economic and Trade Cooperation under the Background of RCEP
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作者 Chit Min Htut 《Open Journal of Applied Sciences》 2024年第4期991-1007,共17页
China and Myanmar are geographically adjacent and have close economic and trade cooperation. China has been Myanmar’s largest trading partner and largest source of investment for many consecutive years. With the offi... China and Myanmar are geographically adjacent and have close economic and trade cooperation. China has been Myanmar’s largest trading partner and largest source of investment for many consecutive years. With the official entry into force of RCEP (Regional Comprehensive Economic Partnership) for Myanmar on May 1, 2022, the reduction of trade tariffs on goods and flexible rules of origin between China and Myanmar will undoubtedly bring more practical results to China Myanmar economic and trade cooperation. However, the implementation of RCEP in Myanmar may face a series of challenges such as poor business environment, weak human resource management, and outdated infrastructure construction. Finally, the article provides countermeasures for China Myanmar economic and trade cooperation from three aspects: optimizing the business environment to attract Chinese investment, increasing investment in education and training to improve labor quality, strengthening infrastructure construction to enhance economic support. 展开更多
关键词 RCEP Myanmar Opportunities CHALLENGES countermeasures
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Agricultural Contamination of the Surface Waters of the Upper Ouémé in Benin: The Case of Heavy Metals and Pesticides
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作者 Armelle Sabine Yélignan Hounkpatin Nonvignon Martial Fassinou +5 位作者 Fadéby Modeste Gouissi Zoulkanerou Orou Piami Dossou Armel Géraldo Houndeton Souradjou Orou Goura Wakili Bolatito Yessoufou Tayéwo Sylvain Biaou 《Journal of Agricultural Chemistry and Environment》 2024年第1期83-99,共17页
Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific samp... Objective: The main objective of this study was to assess the degree of contamination of surface waters by heavy metals and pesticides. Method: To this end, data were collected in December 2022 from four specific sampling stations: Okpara, Térou, Affon and Adjiro. Levels of heavy metals, including cadmium, chromium, copper, iron, mercury, nickel and lead, were measured and subjected to in-depth statistical analysis using graphical summation models. In addition, the concentrations of pesticide active ingredients present in the samples were interpreted and evaluated. The statistical data collected during this study were processed using R software, version 3.5.0. Results: The values obtained at the different stations Okpara, Térou, Affon and Adjiro are respectively Arsenic (2 × 10<sup>-4</sup> mg/L;2.2 × 10<sup>-1</sup> mg/L;1.2 × 10<sup>-4</sup> mg/L;2 × 10<sup>-4</sup> mg/L), Cadmium (4.4 × 10<sup>-5</sup> mg/L;1.1 × 10<sup>-2</sup> mg/L;10<sup>-4</sup> mg/L;4 × 10<sup>-4</sup> mg/L). Then Copper (7 × 10<sup>-4</sup> mg/L;3 × 10<sup>-3</sup> mg/L;7 × 10<sup>-4</sup> mg/L;1 × 10<sup>-4</sup> mg/L), Iron (1.51 mg/L;6.4 × 10<sup>-1</sup> mg/L;2.0012 mg/L;2.9 × 10<sup>-1</sup> mg/L), Lead (0 mg/L;0 mg/L;1.5 × 10<sup>-3</sup> mg/L;1.5 × 10<sup>-3</sup> mg/L). Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (Cadmium, Chromium, Copper, Iron, Mercury, nickel and chromium were not detected in surface waters. It is important to note that the values obtained for trace metals (cadmium, chromium, copper, iron, mercury, nickel and lead) were all below the guideline standards set by the WHO in 2006 for uncontaminated surface waters. This indicates that the surface waters of the Upper Ouémé were below acceptable contamination thresholds in terms of heavy metals. However, the presence of pesticide active ingredients such as cyfluthrin, endosulfan-alpha, endosulfan-beta, profenosfos, tihan, atrazine, gala super and glycel clearly indicates that these surface waters are subject to agricultural contamination. 展开更多
关键词 Agricultural contamination Heavy Metals PESTICIDES Surface Water North Benin
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Eternal Climate Change Patterns and the Causes and Countermeasures of Global Climate Change
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作者 Cuixiang Zhong 《Journal of Environmental Science and Engineering(B)》 2024年第1期9-20,共12页
It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summari... It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summarized the 24 solar terms by observing the annual activities of the sun for a long time,because they ignored the impact of the activities of the moon on the Earth’s climate change on a small scale,the 24 solar terms they summarized often could not accurately predict the change of the Earth’s climate.Therefore,the author studied the influence of lunar activities on the Earth’s climate change,finds out the law of the influence of lunar activities on the Earth’s climate change on a small scale,and summarizes the eternal climate change pattern determined by the activities of the sun and the moon.In addition,the author also reveals the causes and countermeasures of global warming and the frequent occurrence of extreme weather as well as environmental change. 展开更多
关键词 Eternal climate change patterns global warming extreme weather abrupt environmental changes CAUSES countermeasures.
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A Study on the Internal Control and Countermeasures of Fixed Assets in Private Universities:A Case Study of N College
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作者 Guirong Ma Lili Ma 《Proceedings of Business and Economic Studies》 2024年第4期86-92,共7页
Fixed assets in universities occupy an important position in university management due to their wide coverage and large amount of money.Due to insufficient funding supply,private universities mainly focus on the alloc... Fixed assets in universities occupy an important position in university management due to their wide coverage and large amount of money.Due to insufficient funding supply,private universities mainly focus on the allocation and utilization of fixed assets,which reflects the overall characteristics of cautious allocation,maximum utilization,and delayed elimination in the actual management of fixed assets.This article aims to conduct research and analysis on the entire lifecycle process of the allocation,use,and disposal of fixed assets in private universities,summarize the problems existing in the internal control of fixed assets in private universities,and propose corresponding countermeasures and suggestions in a targeted manner. 展开更多
关键词 Private universities Fixed assets Internal control and countermeasures
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Operational Problems and Countermeasures of Public Elective Courses in Higher Vocational Colleges and Universities Based on the Perspective of Academic Affairs Management:Taking Guangdong C Vocational College as an Example
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作者 Jingjie Li 《Journal of Contemporary Educational Research》 2024年第9期277-282,共6页
With the vigorous development of higher vocational education,public elective courses,as one of the core components of the higher vocational curriculum system,occupy a pivotal position.Based on the perspective of acade... With the vigorous development of higher vocational education,public elective courses,as one of the core components of the higher vocational curriculum system,occupy a pivotal position.Based on the perspective of academic affairs management and taking Guangdong C Vocational College as an example,this paper meticulously analyzes the operational problems in the declaration,setting,teaching,and management of public elective courses through questionnaire surveys and other methods.It also puts forward a series of targeted solutions,with a view to continuously improving the teaching quality and management level of public elective courses. 展开更多
关键词 Academic affairs management Public elective courses Operational problems countermeasures Higher vocational colleges and universities
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Features of Tropical Volcanic Rock and Soil of Jakarta-Bandung HSR and Engineering Countermeasures
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作者 ZHAO Dou WANG Shujie ZHENG Mingda(Translated) 《Chinese Railways》 2024年第1期30-37,共8页
The geological features of three types of tropical volcanic rock and soil distributed along Jakarta-Bandung high-speed railway(HSR),including pozzolanic clayey soil,mud shale and deep soft soil,are studied through fie... The geological features of three types of tropical volcanic rock and soil distributed along Jakarta-Bandung high-speed railway(HSR),including pozzolanic clayey soil,mud shale and deep soft soil,are studied through field and laboratory tests.The paper analyzes the mechanism and causes of engineering geological problems caused by tropical volcanic rock and soil and puts forward measures to control subgrade slope instability by rationally determining project type,making side slope stability control and strengthening waterproofing and drainage.The“zero front slope”tunneling technology at the portal,the simplified excavation method of double-side wall heading and the cross brace construction method of arch protection within the semi-open cut row pile frame in the“mountainside”eccentrically loaded soft soil stratum are adopted to control the instability of tunnel side and front slopes,foundation pits and working faces;CFG or pipe piles shall be used to reinforce soft and expansive foundation or replacement measures shall be taken,and the scheme of blind ditch+double-layer water sealing in ballastless track section shall be put forward to prevent arching deformation of foundation;the treatment measures of CFG pile,pipe pile and vacuum combined piled preloading are adopted to improve the bearing capacity of foundation in deep soft soil section and solve the problems of settlement control and uneven settlement.These engineering countermeasures have been applied during the construction of Jakarta-Bandung HSR and achieved good results. 展开更多
关键词 Jakarta-Bandung HSR tropical volcanic rock and soil engineering geological features engineering geological problems engineering countermeasures
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Countermeasures for local scour at offshore wind turbine monopile foundations:A review 被引量:11
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作者 Zi-hao Tang Bruce Melville +4 位作者 Naresh Singhal Asaad Shamseldin Jin-hai Zheng Da-wei Guan Liang Cheng 《Water Science and Engineering》 EI CAS CSCD 2022年第1期15-28,共14页
Local scour at monopile foundations of offshore wind turbines is one of the most critical structural stability issues.This article reviews the contemporary methods of scour countermeasures at monopile foundations.Thes... Local scour at monopile foundations of offshore wind turbines is one of the most critical structural stability issues.This article reviews the contemporary methods of scour countermeasures at monopile foundations.These methods include armouring countermeasures(e.g.,riprap protection)to enhance the anti-scour ability of the bed materials and flow-altering countermeasures(e.g.,collars and sacrificial piles)to reduce downflow or change flow patterns around the monopiles.Stability number and size-selection equations for riprap armour layers are summarised and compared.Moreover,other alternative methods to riprap are briefly introduced and presented.A typical graph of the scour depth reduction with different collar sizes and elevations under specific test conditions is summarised and compared with a plot for a pile founded on a caisson.Reduction rates for different flow-altering countermeasures,including the collar,are listed and compared.A newly developed soil improvement method,namely microbially induced calcite precipitation(MICP),is also reviewed and introduced as a scour protection method.As a popular bio-soil treatment method,MICP has a good potential as a scour countermeasure method.Bio-soil treatment methods and traditional armouring methods are defined as active and passive soil enhancement scour countermeasures,respectively. 展开更多
关键词 Wind turbine foundation Scour countermeasures Armouring countermeasures Flow-altering countermeasures MICP method
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Ultrasonic enhancement of persulfate oxidation system governs emerging pollutants decontamination
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作者 Yanpan Li Yanbo Zhou Yi Zhou 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1666-1678,共13页
Emerging contaminants (ECs) are widely present in aquatic environments, posing potential risks to both ecosystems and human health. Theultrasound-assisted persulfate oxidation process has attracted considerable attent... Emerging contaminants (ECs) are widely present in aquatic environments, posing potential risks to both ecosystems and human health. Theultrasound-assisted persulfate oxidation process has attracted considerable attention in the degradation of ECs due to its ability to generate bothsulfate radicals and cavitation effects, enhancing degradation effects. In this paper, the principle of ultrasonic synergistic Fenton-like oxidationsystem for degrading organic pollutants was reviewed, divided into homogeneous system, non-homogeneous system, and single-atom system toexplore the synergistic effect of ultrasound-enhanced persulfate technology in three aspects, and the effects of environmental factors such asultrasonic frequency and power, system pH, temperature, and initial oxidant concentration on the system's decontamination performance werediscussed. Finally, future research on ultrasonically activated persulfate technology is summarized and prospected. 展开更多
关键词 ULTRASOUND PERSULFATE Emerging contaminants Reaction mechanism Synergistic effects
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Exploring the mechanical behavior and microstructure of compacted loess subjected to dry-wet cycles and chemical contamination
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作者 Yongpeng Nie Wankui Ni +1 位作者 Xiangfei Lü Wenxin Tuo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3673-3695,共23页
Due to climatic factors and rapid urbanization,the soil in the Loess Plateau,China,experiences the coupled effects of dry-wet cycles and chemical contamination.Understanding the mechanical behavior and corresponding m... Due to climatic factors and rapid urbanization,the soil in the Loess Plateau,China,experiences the coupled effects of dry-wet cycles and chemical contamination.Understanding the mechanical behavior and corresponding microstructural evolution of contaminated loess subjected to dry-wet cycles is essential to elucidate the soil degradation mechanism.Therefore,direct shear and consolidation tests were performed to investigate the variations in mechanical properties of compacted loess contaminated with acetic acid,sodium hydroxide,and sodium sulfate during dry-wet cycles.The mechanical response mechanisms were investigated using zeta potential,mineral chemical composition,and scanning electron microscopy(SEM)tests.The results indicate that the mechanical deterioration of sodium hydroxidecontaminated loess during dry-wet cycles decreases with increasing contaminant concentration,which is mainly attributed to the thickening of the electrical double layer(EDL)by Nat and the precipitation of calcite,as well as the formation of colloidal flocs induced by OH,thus inhibiting the development of large pores during the dry-wet process.In contrast,the attenuation of mechanical properties of both acetic acid-and sodium sulfate-contaminated loess becomes more severe with increasing contaminant concentration,with the latter being more particularly significant.This is primarily due to the reduction of the EDL thickness and the erosion of cement in the acidic environment,which facilitates the connectivity of pores during dry-wet cycles.Furthermore,the salt expansion generated by the drying process of saline loess further intensifies the structural disturbance.Consequently,the mechanical performance of compacted loess is sensitive to both pollutant type and concentration,exhibiting different response patterns in the dry-wet cycling condition. 展开更多
关键词 Contaminated loess Dry-wet cycles COMPRESSIBILITY Shear strength Microstructural evolution
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Security Assurance for One-stage Resection of Left Colon Cancer with Acute Obstruction—Thorough and Prompt Enteral Decompression without Contamination 被引量:12
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作者 彭淑牖 何小伟 +3 位作者 刘颖斌 李江涛 王建伟 钱浩然 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第1期8-10,65,共4页
Objective: Thorough, prompt enteral decompression technique without contamination was de- veloped to ensure safety for emergent colon resection and primary anastomosis. Methods: After isolating the mesentery, the “to... Objective: Thorough, prompt enteral decompression technique without contamination was de- veloped to ensure safety for emergent colon resection and primary anastomosis. Methods: After isolating the mesentery, the “to be resected colon segment” was cut at its lower end, then the proximal cut end was put into a plastic bag which was adhered to one side of the operating table. After releasing the clamp, the content could ?ow into this bag. The operator could squeeze the bowel with two hands by turns, from proximal to farness, and from small bowel to large bowel, until the entire bowel content was fully discharged. Then the upper end of this “to be resected colon segment” was cut, and was removed together with the plastic bag. Results: 31 cases of left colon cancer with acute obstruction were decompressed with this technique. They all recovered smoothly, without anastomosis ?stula. Another 6 cases of hepatic seg- mentectomy with incidental colonectomy were decompressed with this technique and had the same results. This technique was also used in di?erent kinds of acute small intestinal obstruction and gained satisfactory results. Conclusion: This technique could be considered as the preferable choice for intraoperative enteral decompression. 展开更多
关键词 enteral decompression left colon one-stage anastomosis peritoneal contamination
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Countermeasures for Qinghai-Tibet Plateau to Cope with Climate Change and Ecological Environment Safety 被引量:7
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作者 伏洋 张国胜 +1 位作者 李凤霞 刘宝康 《Agricultural Science & Technology》 CAS 2010年第1期140-146,共7页
The monitoring,prediction and assessment of status about climate changes and ecological environment at home and abroad were discussed in this study,and the scientific significance and countermeasures for Qinghai-Tibet... The monitoring,prediction and assessment of status about climate changes and ecological environment at home and abroad were discussed in this study,and the scientific significance and countermeasures for Qinghai-Tibet Plateau to cope with these problems were also put forward. 展开更多
关键词 Climate chages Cope with Ecological environment SAFETY Qinghai-Tibet Plateau countermeasures
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