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Coupled bio-chemo-hydro-mechanical modeling of microbially induced calcite precipitation process considering biomass encapsulation using a micro-scale relationship
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作者 Pavan Kumar Bhukya Nandini Adla Dali Naidu Arnepalli 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2775-2789,共15页
Geomaterials with inferior hydraulic and strength characteristics often need improvement to enhance their engineering behaviors.Traditional ground improvement techniques require enormous mechanical effort or synthetic... Geomaterials with inferior hydraulic and strength characteristics often need improvement to enhance their engineering behaviors.Traditional ground improvement techniques require enormous mechanical effort or synthetic chemicals.Sustainable stabilization technique such as microbially induced calcite precipitation(MICP)utilizes bacterial metabolic processes to precipitate cementitious calcium carbonate.The reactive transport of biochemical species in the soil mass initiates the precipitation of biocement during the MICP process.The precipitated biocement alters the hydro-mechanical performance of the soil mass.Usually,the flow,deformation,and transport phenomena regulate the biocementation technique via coupled bio-chemo-hydro-mechanical(BCHM)processes.Among all,one crucial phenomenon controlling the precipitation mechanism is the encapsulation of biomass by calcium carbonate.Biomass encapsulation can potentially reduce the biochemical reaction rate and decelerate biocementation.Laboratory examination of the encapsulation process demands a thorough analysis of associated coupled effects.Despite this,a numerical model can assist in capturing the coupled processes influencing encapsulation during the MICP treatment.However,most numerical models did not consider biochemical reaction rate kinetics accounting for the influence of bacterial encapsulation.Given this,the current study developed a coupled BCHM model to evaluate the effect of encapsulation on the precipitated calcite content using a micro-scale semiempirical relationship.Firstly,the developed BCHM model was verified and validated using numerical and experimental observations of soil column tests.Later,the encapsulation phenomenon was investigated in the soil columns of variable maximum calcite crystal sizes.The results depict altered reaction rates due to the encapsulation phenomenon and an observable change in the precipitated calcite content for each maximum crystal size.Furthermore,the permeability and deformation of the soil mass were affected by the simultaneous precipitation of calcium carbonate.Overall,the present study comprehended the influence of the encapsulation of bacteria on cement morphology-induced permeability,biocement-induced stresses and displacements. 展开更多
关键词 Biocementation process Bio-chemo-hydro-mechanical(BCHM) model Reactive transport ENCAPSULATION micro-scale
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Evaluation of Laboratory Request Forms Completion in a Tertiary Medical Laboratory of the Democratic Republic of Congo
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作者 Mamy Ngole Dahlia Pambu +3 位作者 Nathan Luana Dophie Tshibuela Ritha Nyembu Kibambe Bizette Bizeti Nsangu 《Journal of Biosciences and Medicines》 2024年第6期94-100,共7页
Background: The inadequacy in the completeness of the Laboratory Request Form (LRF) has been reported as one of the major sources of errors during the pre-analytical step of laboratory analysis. To prevent the occurre... Background: The inadequacy in the completeness of the Laboratory Request Form (LRF) has been reported as one of the major sources of errors during the pre-analytical step of laboratory analysis. To prevent the occurrence of such errors, this study aimed at assessing the level of completeness of LRFs. Methods: A retrospective analysis of laboratory request forms was conducted at the Clinical Biology Laboratory of the Kinshasa University Clinic, DR Congo, between November 2021 to May 2022. The LRFs were evaluated according to the completeness of all sections including administrative data of the patient, data of physician who ordered the test, relevant patient’s clinical data and data of the biological sample. Results: From a total of 2842 LRFs evaluated, none was fully completed with all required information. Particularly, patient’s clinical data including the medical history, provisional diagnosis and current treatment, were the most absent in 99% LRFs. However, two sections related to patient’s ID and prescribed test were informed in 100% LRFs. Conclusion: The results of this preanalytical audit can serve as an improvement opportunity focused on strengthening awareness about complete filling of LRF. 展开更多
关键词 AUDIT laboratory Requisition Form Clinical Biology laboratory COMPLETENESS
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Progress in the Study of Laboratory Indicators Related to Acute Pancreatitis
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作者 Jiacheng Song Xiaoping Tan 《Journal of Biosciences and Medicines》 2024年第1期7-18,共12页
Acute pancreatitis (AP) is one of the more common gastrointestinal diseases in clinics and is characterized by rapid progression, many complications, and high mortality. When it develops into severe pancreatitis, its ... Acute pancreatitis (AP) is one of the more common gastrointestinal diseases in clinics and is characterized by rapid progression, many complications, and high mortality. When it develops into severe pancreatitis, its prognosis is poor. Therefore, early assessment of the degree of inflammatory response plays a crucial role in the treatment plan and prognosis of patients. More and more studies have shown that the levels of D-dimer (D-D), angiotensin-2 (Ang-2), phosphate, heparin-binding protein (HBP), retinol-binding protein-4 (RBP4), and osteoblastic protein (OPN) are closely related to the severity of acute pan-creatitis and can be used as effective indicators for early assessment of AP. In this paper, the research progress of the above indicators in assessing the severity of AP is summarized. 展开更多
关键词 Acute Pancreatitis laboratory Indicators PROGRESSION ASSESSMENT
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An ethically guided preclinical device for phenotyping H_(2)production in laboratory rodents
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作者 Victor Pascal-Moussellard Emilie Boucher +7 位作者 Stéphane Tanguy Philippe Cinquin Pierre-Alain Barraud ChloéDavin Cordélia Salomez-Ihl Dalil Hannani François Boucher Jean-Pierre Alcaraz 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第4期553-561,共9页
Background:Dihydrogen(H_(2))is produced endogenously by the intestinal microbiota through the fermentation of diet carbohydrates.Over the past few years,numer-ous studies have demonstrated the significant therapeutic ... Background:Dihydrogen(H_(2))is produced endogenously by the intestinal microbiota through the fermentation of diet carbohydrates.Over the past few years,numer-ous studies have demonstrated the significant therapeutic potential of H_(2)in various pathophysiological contexts,making the characterization of its production in labora-tory species of major preclinical importance.Methods:This study proposes an innovative solution to accurately monitor H_(2)pro-duction in free-moving rodents while respecting animal welfare standards.The devel-oped device consisted of a wire rodent cage placed inside an airtight chamber in which the air quality was maintained,and the H_(2)concentration was continuously analyzed.After the airtightness and efficiency of the systems used to control and maintain air quality in the chamber were checked,tests were carried out on rats and mice with different metabolic phenotypes,over 12 min to 1-h experiments and repeatedly.H_(2)production rates(HPR)were obtained using an easy calculation algorithm based on a first-order moving average.Results:HPR in hyperphagic Zucker rats was found to be twice as high as in control Wistar rats,respectively,2.64 and 1.27 nmol.s^(−1)per animal.In addition,the ingestion of inulin,a dietary fiber,stimulated H_(2)production in mice.HPRs were 0.46 nmol.s^(−1)for animals under control diet and 1.99 nmol.s^(−1)for animals under inulin diet.Conclusions:The proposed device coupled with our algorithm enables fine analysis of the metabolic phenotype of laboratory rats or mice with regard to their endogenous H_(2)production. 展开更多
关键词 hydrogen therapy laboratory rodents MICROBIOTA molecular hydrogen noninvasive monitoring device
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Abnormal Action Detection Based on Parameter-Efficient Transfer Learning in Laboratory Scenarios
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作者 Changyu Liu Hao Huang +2 位作者 Guogang Huang Chunyin Wu Yingqi Liang 《Computers, Materials & Continua》 SCIE EI 2024年第9期4219-4242,共24页
Laboratory safety is a critical area of broad societal concern,particularly in the detection of abnormal actions.To enhance the efficiency and accuracy of detecting such actions,this paper introduces a novel method ca... Laboratory safety is a critical area of broad societal concern,particularly in the detection of abnormal actions.To enhance the efficiency and accuracy of detecting such actions,this paper introduces a novel method called TubeRAPT(Tubelet Transformer based onAdapter and Prefix TrainingModule).Thismethod primarily comprises three key components:the TubeR network,an adaptive clustering attention mechanism,and a prefix training module.These components work in synergy to address the challenge of knowledge preservation in models pretrained on large datasets while maintaining training efficiency.The TubeR network serves as the backbone for spatio-temporal feature extraction,while the adaptive clustering attention mechanism refines the focus on relevant information.The prefix training module facilitates efficient fine-tuning and knowledge transfer.Experimental results demonstrate the effectiveness of TubeRAPT,achieving a 68.44%mean Average Precision(mAP)on the CLA(Crazy LabActivity)small-scale dataset,marking a significant improvement of 1.53%over the previous TubeR method.This research not only showcases the potential applications of TubeRAPT in the field of abnormal action detection but also offers innovative ideas and technical support for the future development of laboratory safety monitoring technologies.The proposed method has implications for improving safety management systems in various laboratory environments,potentially reducing accidents and enhancing overall workplace safety. 展开更多
关键词 Parameter-efficient transfer learning laboratory scenarios TubeRAPT abnormal action detection
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Impact of numerous larval diets on the biology of pink bollworm Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae)under laboratory conditions
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作者 AKHTAR Shamim ARIF Muhammad Jalal +1 位作者 GOGI Muhammad Dildar HAQ Imran-ul 《Journal of Cotton Research》 CAS 2024年第1期69-78,共10页
Background Pink bollworm,Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae)has become a poten-tial pest of cotton by causing substantial yield losses around the world including Pakistan.Keeping in view the fa... Background Pink bollworm,Pectinophora gossypiella(Saunders)(Lepidoptera:Gelechiidae)has become a poten-tial pest of cotton by causing substantial yield losses around the world including Pakistan.Keeping in view the facts like limited research investigations,unavailability,and high cost of artificial diet’s constituents and their premixes,the present research investigations on the dietary aspect of P.gossypiella were conducted.The larvae of P.gossypiella were reared on different diets that were prepared using indigenous elements.The standard/laboratory diet com-prised of wheat germ meal 34.5 g,casein 30.0 g,agar–agar 20.0 g,sucrose 10.0 g,brewer’s yeast 5.0 g,α-cellulose 1.0 g,potassium-sorbate1.5 g,niplagin 0.5 g,decavitamin 0.01 g,choline-chloride 0.06 g,maize-oil 3.30 g,honey 2.0 g,and water 730.0 mL.Alternatives to cotton bolls and wheat germ meal were okra seed sprouts,okra fruit,cottonseed meal,and okra seed meals,which were included in the study to introduce an efficient and economic mass-rearing system.Results The larval development completed in 19.68d±0.05 d with a weight of 20.18mg±0.20 mg at the fourth instar fed on the cottonseed meal-based diet instead of wheat germ meal based diet.On the same diet,84.00%±4.00%,17.24 mg±0.03 mg,and 7.76d±0.06 d were recorded as pupae formation,pupal weight,and pupal duration,respectively.Adult emergence,76.00%±1.00%was recorded from pupae collected from larvae raised on cottonseed meal-based diet.These male and female moths lived for 40.25d±0.10 d,and 44.34d±0.11 d,respectively.Females deposited 21.28±0.04 eggs per day with the viability of 65.78%±0.14%.The larval mortal-ity at the fourth instar was 37.20%±1.36%and malformed pupation of 12.00%±1.41%was recorded.Replacement of wheat germ meal with that of local meals(cottonseed and okra seed)in the standard laboratory diet has saved 463.80 to 467.10 PKR with 1.62 to 1.63 cost economic returns,respectively.Conclusion This research is of novel nature as it provides a concise and workable system for the economic and suc-cessful rearing of P.gossypiella under laboratory conditions. 展开更多
关键词 Artificial diets Cottonseed meal laboratory rearing Pectinophora gossypiella Wheat germ meal
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Risk Prediction Model for Hypertensive Disorders of Pregnancy Based on Routine Laboratory Indicators and Risk Factors: A Retrospective Analysis
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作者 Yiqv Zeng Yu Cai 《Open Journal of Obstetrics and Gynecology》 2024年第9期1303-1321,共19页
Background: Hypertensive disorder of pregnancy (HDP) is a group of diseases in which pregnancy and elevated blood pressure coexist. There is still a lack of reliable clinical tools to predict the incidence of HDP. The... Background: Hypertensive disorder of pregnancy (HDP) is a group of diseases in which pregnancy and elevated blood pressure coexist. There is still a lack of reliable clinical tools to predict the incidence of HDP. The purpose of this study was to establish and validate a nomogram prediction model for assessing the risk of HDP in pregnant women based on laboratory indicators and HDP risk factors. Method: A total of 307 pregnant women who were hospitalized in the obstetrics and gynecology department of our hospital were included in this study, and were randomly divided into a training cohort and validation cohort at a ratio of 7:3. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors for the development of HDP on laboratory indicators as well as risk factors for HDP in the training cohort of patients. The results of the multivariate regression model were visualized by forest plots. A nomogram was constructed based on the results of multivariate logistic regression to predict the risk of HDP in pregnant women. The validity of the risk prediction model was evaluated by the area under the receiver operating characteristic curve (AUC), the consistency index (C-index), the calibration curve and the decision curve analysis (DCA). Results: BMI ≥ 25 Kg/m2, total cholesterol in early pregnancy, uric acid and proteinuria in late pregnancy were independent risk factors for HDP. The AUC and C-index of the nomogram constructed by the above four factors were both 0.848. The calibration curve is closely fitted with the ideal diagonal, showing a good consistency between the nomogram prediction and the actual observation of HDP. The DCA has demonstrated the great clinical utility of nomogram. Internal verification proves the reliability of the predicted nomograms. Conclusion: The BTUP nomogram model based on laboratory indicators and risk factors proposed in this study showed good predictive value for the risk assessment of HDP. It is expected to provide evidence for clinical prediction of the risk of HDP in pregnant women. 展开更多
关键词 Hypertensive Disorders of Pregnancy NOMOGRAM laboratory Indicators Risk Factors
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Re-evaluating the necessity of routine laboratory monitoring during isotretinoin therapy for acne
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作者 Yun-Xia Zhu Liang Wu +5 位作者 Sheng-Cai Zhu Xiu-Ping Wang Deng Zhang Yan-Ping Tan Xiao-Liang Ouyang Chun-Ming Li 《World Journal of Clinical Cases》 SCIE 2024年第28期6237-6240,共4页
In this letter,we discuss the topic of necessity of routine laboratory monitoring during isotretinoin treatment for acne.According to Park and colleagues,it is advisable to monitor the levels of triglycerides,alanine ... In this letter,we discuss the topic of necessity of routine laboratory monitoring during isotretinoin treatment for acne.According to Park and colleagues,it is advisable to monitor the levels of triglycerides,alanine aminotransferase,and aspartate aminotransferase every 5 to 6 months.Additionally,the levels of total cholesterol and low-density lipoprotein should be checked within the first two months of treatment.Isotretinoin is a commonly prescribed agent mainly used to treat acne.Despite its high effectiveness,it necessitates regular monitoring of laboratory parameters due to its side effect profile.Currently,there remains a lack of consensus on the appropriate frequency for monitoring these parameters during treatment with isotretinoin.This letter will provide insight into this complex and controversial topic.Based on existing literature,we concluded that the incidence of changes in lipid and liver aminotransferase levels during isotretinoin treatment for acne was low and likely clinically insignificant.For generally healthy people,we recommend testing lipid and liver profiles once at baseline and a second time at the peak dosage.However,frequent testing might still be beneficial in certain populations of patients. 展开更多
关键词 ACNE ISOTRETINOIN laboratory monitoring Liver function Blood lipids
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Impact of Laboratory Value Flowsheet in Electronic Health Record (EHR) Documentation Time
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作者 Isabel Rosado Pogozelski 《Open Journal of Nursing》 2024年第1期40-50,共11页
Research on the use of EHR is contradictory since it presents contradicting results regarding the time spent documenting. There is research that supports the use of electronic records as a tool to speed documentation;... Research on the use of EHR is contradictory since it presents contradicting results regarding the time spent documenting. There is research that supports the use of electronic records as a tool to speed documentation;and research that found that it is time consuming. The purpose of this quantitative retrospective before-after project was to measure the impact of using the laboratory value flowsheet within the EHR on documentation time. The research question was: “Does the use of a laboratory value flowsheet in the EHR impact documentation time by primary care providers (PCPs)?” The theoretical framework utilized in this project was the Donabedian Model. The population in this research was the two PCPs in a small primary care clinic in the northwest of Puerto Rico. The sample was composed of all the encounters during the months of October 2019 and December 2019. The data was obtained through data mining and analyzed using SPSS 27. The evaluative outcome of this project is that there is a decrease in documentation time after implementation of the use of the laboratory value flowsheet in the EHR. However, patients per day increase therefore having an impact on the number of patients seen per day/week/month. The implications for clinical practice include the use of templates to improve workflow and documentation as well as decreasing documentation time while also increasing the number of patients seen per day. . 展开更多
关键词 Electronic Health Record EHR laboratory Results Template Documentation Time
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Laboratory or Department?Exploration and Creation in Computer Science and Technology
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作者 Ann Copestake 《计算机教育》 2024年第3期13-16,共4页
In the very beginning,the Computer Laboratory of the University of Cambridge was founded to provide computing service for different disciplines across the university.As computer science developed as a discipline in it... In the very beginning,the Computer Laboratory of the University of Cambridge was founded to provide computing service for different disciplines across the university.As computer science developed as a discipline in its own right,boundaries necessarily arose between it and other disciplines,in a way that is now often detrimental to progress.Therefore,it is necessary to reinvigorate the relationship between computer science and other academic disciplines and celebrate exploration and creativity in research.To do this,the structures of the academic department have to act as supporting scaffolding rather than barriers.Some examples are given that show the efforts being made at the University of Cambridge to approach this problem. 展开更多
关键词 laboratory or department University of Cambridge Boundaries Exploration and creativity
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Detection Algorithm of Laboratory Personnel Irregularities Based on Improved YOLOv7
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作者 Yongliang Yang Linghua Xu +2 位作者 Maolin Luo Xiao Wang Min Cao 《Computers, Materials & Continua》 SCIE EI 2024年第2期2741-2765,共25页
Due to the complex environment of the university laboratory,personnel flow intensive,personnel irregular behavior is easy to cause security risks.Monitoring using mainstream detection algorithms suffers from low detec... Due to the complex environment of the university laboratory,personnel flow intensive,personnel irregular behavior is easy to cause security risks.Monitoring using mainstream detection algorithms suffers from low detection accuracy and slow speed.Therefore,the current management of personnel behavior mainly relies on institutional constraints,education and training,on-site supervision,etc.,which is time-consuming and ineffective.Given the above situation,this paper proposes an improved You Only Look Once version 7(YOLOv7)to achieve the purpose of quickly detecting irregular behaviors of laboratory personnel while ensuring high detection accuracy.First,to better capture the shape features of the target,deformable convolutional networks(DCN)is used in the backbone part of the model to replace the traditional convolution to improve the detection accuracy and speed.Second,to enhance the extraction of important features and suppress useless features,this paper proposes a new convolutional block attention module_efficient channel attention(CBAM_E)for embedding the neck network to improve the model’s ability to extract features from complex scenes.Finally,to reduce the influence of angle factor and bounding box regression accuracy,this paper proposes a newα-SCYLLA intersection over union(α-SIoU)instead of the complete intersection over union(CIoU),which improves the regression accuracy while increasing the convergence speed.Comparison experiments on public and homemade datasets show that the improved algorithm outperforms the original algorithm in all evaluation indexes,with an increase of 2.92%in the precision rate,4.14%in the recall rate,0.0356 in the weighted harmonic mean,3.60%in the mAP@0.5 value,and a reduction in the number of parameters and complexity.Compared with the mainstream algorithm,the improved algorithm has higher detection accuracy,faster convergence speed,and better actual recognition effect,indicating the effectiveness of the improved algorithm in this paper and its potential for practical application in laboratory scenarios. 展开更多
关键词 University laboratory personnel behavior YOLOv7 deformable convolutional networks attention module intersection over union
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Field and Laboratory Study of Accumulated Debrisflow-Forming Solid Mass Sediment on the Example of River Chokheltkhevi (Mtskheta-Mtianeti Region, Georgia)
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作者 Zurab Varazashvili Zurab Kakulia +2 位作者 George Gaprindashvili Goga Chakhaia Irakli Ramishvili 《Journal of Geoscience and Environment Protection》 2024年第6期151-160,共10页
The paper presents the results of the field and laboratory research carried out in the Chokheltkhevi river basin, according to which the sediment-forming solid mass accumulated in the bed of the Chokhelthkhevi river w... The paper presents the results of the field and laboratory research carried out in the Chokheltkhevi river basin, according to which the sediment-forming solid mass accumulated in the bed of the Chokhelthkhevi river was recorded and its granulometric and chemical composition, as well as physical-mechanical characteristics, were studied. Based on the results of the research, it can be said that in the debrisflow channel of the Chokheltkhevi River, coarse and sandy-clay soils are mainly accumulated, which represent an unstable mass for the expected debrisflow in the gorge, which, together with other geological, hydrological and climatic factors, helps to increase the scale of the expected ecological danger. According to the results of the laboratory research, it can be concluded that the soil accumulated in the drainage channel is low in ion concentration, and the humus content in it is minimal, which indicates the possibility of easy displacement of the solid mass accumulated in the drainage channel and, accordingly, the risk of a catastrophic debrisflow. 展开更多
关键词 Georgia GEOLOGY Debrisflow MUDFLOW laboratory
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Direct measurement of the break-out ^(19)F(p,γ)^(20)Ne reaction in the China Jinping underground laboratory(CJPL)
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作者 Yin‑Ji Chen Hao Zhang +28 位作者 Li‑Yong Zhang Jian‑Jun He Richard James deBoer Michael Wiescher Alexander Heger David Kahl Jun Su Daniel Odell Xin‑Yue Li Jian‑Guo Wang Long Zhang Fu‑Qiang Cao Zhi‑Cheng Zhang Xin‑Zhi Jiang Luo‑Huan Wang Zi‑Ming Li Lu‑Yang Song Liang‑Ting Sun Qi Wu Jia‑Qing Li Bao‑Qun Cui Li‑Hua Chen Rui‑Gang Ma Er‑Tao Li Gang Lian Yao‑De Sheng Zhi‑Hong Li Bing Guo Wei‑Ping Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期142-152,共11页
Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in astrophysics.As one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle w... Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in astrophysics.As one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle was thought to be the source of the calcium observed in these oldest stars.However,according to the stellar modeling,a nearly tenfold increase in the thermonuclear rate ratio of the break-out ^(19)F(p,γ)^(20) Ne reaction with respect to the competing ^(19)F(p,α)^(16) O back-processing reaction is required to reproduce the observed calcium abundance.We performed a direct measurement of this break-out reaction at the China Jinping underground laboratory.The measurement was performed down to the low-energy limit of E_(c.m.)=186 keV in the center-of-mass frame.The key resonance was observed at 225.2 keV for the first time.At a temperature of approximately 0.1 GK,this new resonance enhanced the thermonuclear ^(19)F(p,γ)^(20) Ne rate by up to a factor of≈7.4,compared with the previously recommended NACRE rate.This is of particular interest to the study of the evolution of the first stars and implies a stronger breakdown in their“warm”CNO cycle through the ^(19)F(p,γ)^(20) Ne reaction than previously envisioned.This break-out resulted in the production of the calcium observed in the oldest stars,enhancing our understanding of the evolution of the first stars. 展开更多
关键词 Nuclear astrophysics First stars Abundance of calcium Reaction cross section Reaction rate China Jinping underground laboratory(CJPL) JUNA
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National Key Laboratory of Baiyun Obo Rare Earth Resource Researches and Comprehensive Utilization
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《China Rare Earth Information》 2024年第1期F0002-F0002,共1页
National Key Laboratory of Baiyun Obo Rare Earth Resource Researches and Comprehensive Utilization was approved by the Ministry of Science and Technology to be one of the national key laboratories in November 2022.The... National Key Laboratory of Baiyun Obo Rare Earth Resource Researches and Comprehensive Utilization was approved by the Ministry of Science and Technology to be one of the national key laboratories in November 2022.The laboratory was reconstructed based on former State Key Laboratory of Baiyun Obo Rare Earth Resources Researches and Comprehensive Utilization.The key laboratory takes Baotou Research Institute of Rare Earths as the main research body,cooperating with scientific and technological strength from Lanzhou University and Changsha Research Institute of Mining and Metallurgy. 展开更多
关键词 KEY EARTH laboratory
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Enhancing Hazardous Chemical Management in Chinese University Laboratories:Strategies for Safety and Efficiency
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作者 Yizhe Li 《Journal of Electronic Research and Application》 2024年第1期1-6,共6页
This paper examines the management of hazardous chemicals in Chinese university laboratories,identifying key challenges and proposing improvements.It reviews current practices and safety measures,highlighting deficien... This paper examines the management of hazardous chemicals in Chinese university laboratories,identifying key challenges and proposing improvements.It reviews current practices and safety measures,highlighting deficiencies such as inadequate safety systems and insufficient awareness among personnel.The study emphasizes the necessity of tailored safety management systems,the integration of digital tracking technologies like Radio Frequency Identification,and enhanced safety training for staff.The proposed recommendations aim to mitigate risks and enhance laboratory safety and efficiency.In conclusion,the paper asserts that a comprehensive approach,encompassing improved management systems,technological advancements,and educational initiatives,is essential for safer chemical handling in academic research environments. 展开更多
关键词 Hazardous chemicals laboratory safety RFID technology Safety management Chinese universities
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Evaluation of Technical Education by Using a Modern Structured MOODLE Laboratory Course, in Relation to Recent Data
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作者 Gerasimos Vlassopoulos George Albert Karikas +4 位作者 Efstathia Papageorgiou Ioannis Psaromiligkos Niki Giannouli Pigi Vlassopoulou Petros Karkalousos 《Journal of Intelligent Learning Systems and Applications》 2024年第3期316-339,共24页
E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a mo... E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a modern structured MOODLE interactive course, designed for the needs of the laboratory course “Automotive Systems”. The study concerns Greek secondary vocational education pupils aged 18 and vocational training adult students aged 20 to 50 years. The multistage, equal size simple random cluster sample was used as a sampling method. Pupils and adult students of each cluster completed structured 10-question questionnaires both before and after attending the course. A total of 120 questionnaires were collected. In general, our findings disclosed that the majority of pupils and adult students had significantly improved their knowledge and skills from using MOODLE. They reported strengthening conventional teaching, using the new MOODLE technology. The satisfaction indices improved quite, with the differences in their mean values being statistically significant. 展开更多
关键词 Information and Communication Technologies (ICT) Distance Learning E-Learning Students’ Opinions Education in Greece I.C.T. in Greece STUDENTS Pupils Adults Adult Students MOODLE MOOC (V.H.S.) Vocational High Schools (S.H.V.T.) Schools of Higher Vocational Training VOCATIONAL Profession Interactive Lessons Courses Training laboratory Course Secondary Education Automotive Systems Car Systems
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Numerical Analysis of a Spiral-groove Dry-gas Seal Considering Micro-scale Effects 被引量:12
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作者 WANG Bing ZHANG Huiqiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第1期146-153,共8页
A dry-gas seal system is a non-contact seal technology that is widely used in different industrial applications.Spiral-groove dry-gas seal utilizes fluid dynamic pressure effects to realize the seal and lubrication pr... A dry-gas seal system is a non-contact seal technology that is widely used in different industrial applications.Spiral-groove dry-gas seal utilizes fluid dynamic pressure effects to realize the seal and lubrication processes,while forming a high pressure gas film between two sealing faces due to the deceleration of the gas pumped in or out.There is little research into the effects and the influence on seal performance,if the grooves and the gas film are at the micro-scale.This paper investigates the micro-scale effects on spiral-groove dry-gas seal performance in a numerical solution of a corrected Reynolds equation.The Reynolds equation is discretized by means of the finite difference method with the second order scheme and solved by the successive-over-relaxation(SOR) iterative method.The Knudsen number of the flow in the sealing gas film is changed from 0.005 to 0.120 with a variation of film depth and sealing pressure.The numerical results show that the average pressure in the gas film and the sealed gas leakage increase due to micro-scale effects.The open force is enlarged,while the gas film stiffness is significantly decreased due to micro-scale effects.The friction torque and power consumption remain constant,even in low sealing pressure and spin speed conditions.In this paper,the seal performance at different rotor face spin speeds is also described.The proposed research clarifies the micro-scale effects in a spiral-groove dry-gas seal and their influence on seal performance,which is expected to be useful for the improvement of the design of dry-gas seal systems operating in the slip flow regime. 展开更多
关键词 micro-scale effect spiral-groove dry-gas seal numerical analysis Reynolds equation
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Discharge characteristics of a needle-to-plate electrode at a micro-scale gap 被引量:8
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作者 王荣刚 季启政 +3 位作者 张桐恺 夏清 张宇 欧阳吉庭 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第5期126-130,共5页
To understand the discharge characteristics under a gap of micrometers,the breakdown voltage and current–voltage curve are measured experimentally in a needle-to-plate electrode at a microscale gap of 3–50 μm in ai... To understand the discharge characteristics under a gap of micrometers,the breakdown voltage and current–voltage curve are measured experimentally in a needle-to-plate electrode at a microscale gap of 3–50 μm in air.The effect of the needle radius and the gas pressure on the discharge characteristics are tested.The results show that when the gap is larger than 10 μm,the relation between the breakdown voltage and the gap looks like the Paschen curve;while below 10 μm,the breakdown voltage is nearly constant in the range of the tested gap.However,at the same gap distance,the breakdown voltage is still affected by the pressure and shows a trend similar to Paschen's law.The current–voltage characteristic in all the gaps is similar and follows the trend of a typical Townsend-to-glow discharge.A simple model is used to explain the non-normality of breakdown in the micro-gaps.The Townsend mechanism is suggested to control the breakdown process in this configuration before the gap reduces much smaller in air. 展开更多
关键词 needle-to-plate electrode micro-scale gap gas breakdown
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Recent Advances in Computational Simulation of Macro-,Meso-,and Micro-Scale Biomimetics Related Fluid Flow Problems 被引量:5
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作者 Y. Y. Yan 《Journal of Bionic Engineering》 SCIE EI CSCD 2007年第2期97-107,共11页
Over the last decade, computational methods have been intensively applied to a variety of scientific researches and engineering designs. Although the computational fluid dynamics (CFD) method has played a dominant r... Over the last decade, computational methods have been intensively applied to a variety of scientific researches and engineering designs. Although the computational fluid dynamics (CFD) method has played a dominant role in studying and simulating transport phenomena involving fluid flow and heat and mass transfers, in recent years, other numerical methods for the simulations at meso- and micro-scales have also been actively applied to solve the physics of complex flow and fluid-interface interactions. This paper presents a review of recent advances in multi-scale computational simulation of biomimetics related fluid flow problems. The state-of-the-art numerical techniques, such as lattice Boltzmann method (LBM), molecular dynamics (MD), and conventional CFD, applied to different problems such as fish flow, electro-osmosis effect of earthworm motion, and self-cleaning hydrophobic surface, and the numerical approaches are introduced. The new challenging of modelling biomimetics problems in developing the physical conditions of self-clean hydrophobic surfaces is discussed. 展开更多
关键词 biomimetics computational simulation macro- meso- micro-scale HYDROPHOBIC SURFACES
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Thermoelastic vibration analysis of micro-scale functionally graded material fluid-conveying pipes in elastic medium 被引量:2
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作者 TONG Guo-jun LIU Yong-shou +1 位作者 LIU Hui-chao DAI Jia-yin 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第10期2785-2796,共12页
Micro-scale functionally graded material(FGM)pipes conveying fluid have many significant applications in engineering fields.In this work,the thermoelastic vibration of FGM fluid-conveying tubes in elastic medium is st... Micro-scale functionally graded material(FGM)pipes conveying fluid have many significant applications in engineering fields.In this work,the thermoelastic vibration of FGM fluid-conveying tubes in elastic medium is studied.Based on modified couple stress theory and Hamilton’s principle,the governing equation and boundary conditions are obtained.The differential quadrature method(DQM)is applied to investigating the thermoelastic vibration of the FGM pipes.The effect of temperature variation,scale effect of the microtubule,micro-fluid effect,material properties,elastic coefficient of elastic medium and outer radius on thermoelastic vibration of the FGM pipes conveying fluid are studied.The results show that in the condition of considering the scale effect and micro-fluid of the microtubule,the critical dimensionless velocity of the system is higher than that of the system which calculated using classical macroscopic model.The results also show that the variations of temperature,material properties,elastic coefficient and outer radius have significant influences on the first-order dimensionless natural frequency. 展开更多
关键词 functionally graded materials thermoelastic vibration micro-scale micro-fluid
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