检索结果-南通市图书馆

Optimization of Cellulose Nanocrystal Isolation from Ayous Sawdust Using Response Surface Methodology

Journal of Materials Science and Chemical Engineering 2024年第1期12卷 36-55页

作者： Tchigo Alifa Hamida Aminatou Oumar Said jean-Bosco Tchatchueng Department of Chemical Engineering School of Chemical Engineering and Mineral Industries University of Ngaoundere Ngaoundere Cameroon Department of Applied Chemistry National Advanced School of Agro-Industrial Sciences University of Ngaoundere Ngaoundere Cameroon Department in Charge of Coordination and Valorisation of Research National Advanced School of Engineering University of Yaounde 1 Yaounde Cameroon

This study focuses on the extraction of cellulose nanocrystals (CNC), from microcrystalline cellulose (MCC), derived from Ayous sawdust. The process involves multiple steps and a large amount of chemical products. The objective of this research was to determine the effects of factors that impact the isolation process and to identify the optimal conditions for CNC isolation by using the response surface methodology. The factors that varied during the process were the quantity of MCC, the concentration of sulfuric acid, the hydrolysis time and temperature, and the ultrasonic treatment time. The response measured was the yield. The study found that with 5.80 g of microcrystalline cellulose, a sulfuric acid concentration of 63.50% (w/w), a hydrolysis time of 53 minutes, a hydrolysis temperature of 69˚C, and a sonication time of 19 minutes are the ideal conditions for isolation. The experimental yield achieved was (37.84 ± 0.99) %. The main factors influencing the process were the sulfuric acid concentration, hydrolysis time and temperature, with a significant influence (p < 0.05). Infrared characterization results showed that nanocrystals were indeed isolated. With a crystallinity of 35.23 and 79.74, respectively, for Ayous wood fiber and nanocrystalline cellulose were observed by X-ray diffraction, with the formation of type II cellulose, thermodynamically more stable than native cellulose type I.

关键词： Ayous Sawdust Lignocellulosic Waste Isolation Cellulose Nanocrystals Optimization Response Surface Methodology

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The efficacy of vitamin E in preventing arthrofibrosis after joint replacement

引用

Animal Models and Experimental Medicine 2024年第2期7卷 145-155页

作者： Yingfang Fan jean Yuh Sashank Lekkala Mehmet D.Asik Andrew Thomson Madeline McCanne Mark A.Randolph Antonia F.Chen Ebru Oral Harris Orthopaedic Laboratory Department of Orthopaedic SurgeryMassachusetts General HospitalBostonMassachusettsUSA Department of Orthopaedic Surgery Harvard Medical SchoolBostonMassachusettsUSA Department of Surgery Harvard Medical SchoolBostonMassachusettsUSA Department of Orthopaedic Surgery Brigham and Women's HospitalBostonMassachusettsUSA

Background:Arthrofibrosis is a joint disorder characterized by excessive scar formation in the joint *** E is an antioxidant with potential anti-fibroblastic *** aim of this study was to establish an arthrofibrosis rat model after joint replacement and assess the effects of vitamin E supplementation on joint ***:We simulated knee replacement in 16 male Sprague–Dawley *** immobilized the surgical leg with a suture in full *** control groups were killed at 2 and 12 weeks(n=5 per group),and the test group was supplemented daily with vitamin E(0.2 mg/mL)in their drinking water for 12 weeks(n=6).We performed histological staining to investigate the presence and severity of *** staining andα2-macroglobulin(α2M)enzyme-linked immunosorbent assay(ELISA)were used to assess local and systemic *** weight bearing(total internal reflection)and range of motion(ROM)were collected for functional ***:The ROM and weight-bearing symmetry decreased after the procedure and recovered slowly with still significant deficit at the end of the study for both *** analysis confirmed fibrosis in both lateral and posterior periarticular *** E supplementation showed a moderate anti-inflammatory effect on the local and systemic *** vitamin E group exhibited significant improvement in ROM and weight-bearing symmetry at day 84 compared to the control ***:This model is viable for simulating arthrofibrosis after joint *** E may benefit postsurgical arthrofibrosis,and further studies are needed for dosing requirements.

关键词： arthrofibrosis range of motion total knee arthroplasty vitamin E

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Numerical Study of the Vibrations of Beams with Variable Stiffness under Impulsive or Harmonic Loading

引用

World Journal of Engineering and Technology 2024年第2期12卷 401-425页

作者： Moussa Sali Fabien Kenmogne jean Bertin Nkibeu Abdou Njifenjou Laboratory of Materials Mechanics and Civil Engineering National Higher Polytechnic School of Maroua University of Maroua Maroua Cameroon Department of Civil Engineering Advanced Teachers Training College of the Technical Education University of Douala Douala Cameroon Laboratory Engineering Civil and Mechanics National Advanced School of Engineering University of Yaound&#233 1 Yaound&#233 Cameroon Laboratory of Energy Materials Modeling and Method (E3M) National Advanced School of Engineering University of Douala Douala Cameroon Laboratory of Mathematical Engineering and Information Systems National Advanced School of Engineering University of Yaound&#233 1 Yaound&#233 Cameroon

The behavior of beams with variable stiffness subjected to the action of variable loadings (impulse or harmonic) is analyzed in this paper using the successive approximation method. This successive approximation method is a technique for numerical integration of partial differential equations involving both the space and time, with well-known initial conditions on time and boundary conditions on the space. This technique, although having been applied to beams with constant stiffness, is new for the case of beams with variable stiffness, and it aims to use a quadratic parabola (in time) to approximate the solutions of the differential equations of dynamics. The spatial part is studied using the successive approximation method of the partial differential equations obtained, in order to transform them into a system of time-dependent ordinary differential equations. Thus, the integration algorithm using this technique is established and applied to examples of beams with variable stiffness, under variable loading, and with the different cases of supports chosen in the literature. We have thus calculated the cases of beams with constant or variable rigidity with articulated or embedded supports, subjected to the action of an instantaneous impulse and harmonic loads distributed over its entire length. In order to justify the robustness of the successive approximation method considered in this work, an example of an articulated beam with constant stiffness subjected to a distributed harmonic load was calculated analytically, and the results obtained compared to those found numerically for various steps (spatial h and temporal τ ¯ ) of calculus, and the difference between the values obtained by the two methods was small. For example for ( h=1/8 , τ ¯ =1/ 64 ), the difference between these values is 17%.

关键词： Successive Approximations Method Direct Integration Differential Equations Beams of Variable Stiffness Quadratic Parabola Impulse and Harmonic Loads

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Epidemiological and Computed Tomography Aspects of Facial Trauma at Kira Hospital in Bujumbura

引用

Open Journal of Radiology 2024年第2期14卷 83-91页

作者： Sébastien Manirakiza jean Marie Banziriyubusa Stany Harakandi Patrice Barasukana Chantal Murekatete Daniel Nduwayo jean Bosco Bizimana Léopold Nzisabira Department of Radiology Teaching Hospital of Kamenge Bujumbura Burundi Department of Anesthesia and Resuscitation Teaching Hospital of Kamenge Bujumbura Burundi Department of Internal Medicine (Neurology) Teaching Hospita lof Kamenge Bujumbura Burundi Department of Surgery (Neurosurgery) Teaching Hospital of Kamenge Bujumbura Burundi

Background: Maxillofacial trauma affects young adults more. The injury assessment is difficult to establish in low-income countries because of the imaging means, particularly the scanner, which is poorly available and less financially accessible. The aim of this study is to describe the epidemiological profile and the various tomodensitometric aspects of traumatic lesions of the face in patients received in the Radiology department of Kira Hospital. Patients and methods: This is a descriptive retrospective study involving 104 patients of all ages over a period of 2 years from December 2018 to November 2019 in the medical imaging department of KIRA HOSPITAL. We included in our study any patient having undergone a CT scan of the head and presenting at least one lesion of the facial mass, whether associated with other cranioencephalic lesions. Results: Among the 384 patients received for head trauma, 104 patients (27.1% of cases) presented facial damage. The average age of our patients was 32.02 years with extremes of 8 months and 79 years. In our study, 87 of the patients (83.6%) were male. The road accident was the circumstance in which facial trauma occurred in 79 patients (76% of cases). These injuries were accompanied by at least one bone fracture in 97 patients (93.3%). Patients with fractures of more than 3 facial bones accounted for 40.2% of cases and those with fractures of 2 to 3 bones accounted for 44.6% of cases. The midface was the site of the fracture in 85 patients (87.6% of cases). Orbital wall fractures were noted in 57 patients (58.8% of cases) and the jawbone was the site of a fracture in 50 patients (51.5% of cases). In the vault, the fractures involved the extra-facial frontal bone (36.1% of cases) and temporal bone (18.6% of cases). Cerebral contusion was noted in 41.2% of patients and pneumoencephaly in 15.5% of patients. Extradural hematoma was present in 16 patients and subdural hematoma affected 13 patients. Conclusion: Computed tomography is

关键词： Road Accident CT-Scan Facial Trauma

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Hydrogeochemical Characterization of Groundwater from Fissured Aquifers in the Angovia Mine Operating Permit Area (Central-West Côte d’Ivoire)

引用

Journal of Water Resource and Protection 2024年第1期16卷 83-101页

作者： Kouadio Michel Yao Tanina Drissa Soro Tanoh jean Jacques Koua Akaie jean Fabrice Tchakray Yao Emile Desmond Konan Brou Dibi Laboratory of Sciences and Technologies of Environment University Jean Lorougnon Guede Daloa C&ocircte d’Ivoire

The main objective of this study is to determine the hydrogeochemical specificities of the groundwater of the Angovia mine operating permit, located in the Yaouré mountains in the center-west of Côte d’Ivoire. To do so, descriptive and multivariate statistical analysis methods with the SOM (Self Organizing Maps) algorithm were applied to the physicochemical parameters of 17 boreholes using the calcite (ISC) and dolomite (ISD) saturation indices. The results obtained have shown that the groundwater in the Angovia mine operating permit area has an average temperature of 27.52°C (long rainy season) and 27.87°C (long dry season) and has an average pH of 7.09 ± 0.35 during the main rainy season and 7.32 ± 0.35 during the main dry season. They are mineralized with an average electrical conductivity of 505.98 ± 302.85 μS/cm during the long rainy season and with 450.33 ± 233.74 μS/cm as average during the long dry season. The main phenomena at the origin of groundwater mineralization are water residence time, oxidation-reduction and surface inflow. The study of the relative age of the water shows that the groundwater in the Angovia mine operating permit area is mainly undersaturated with respect to calcite and dolomite. They are therefore very old in the aquifer with a slow circulation speed during the long rainy season and the long dry season.

关键词： Hydrogeochemistry Mineralization Fissure Aquifers Operating Permits The Angovia Mine

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

对电动汽车购买意愿的探索：考察外国人抵达中国后购买电动汽车意愿的影响因素

对电动汽车购买意愿的探索：考察外国人抵达中国后购买电动汽车意...

引用

作者： HUMBERT jean MICHEL BERNARD 华东师范大学

学位级别：硕士

来源：

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Dosage Formula in Anesthesia for Manual Intrauterine Aspiration Post-Abortion in Resource-Limited Settings

引用

Pharmacology & Pharmacy 2024年第4期15卷 71-80页

作者： Serge Ibula Rivain Iteke Berthe Barhayiga Doddie Tsansya Roger Cishugi jean Jacques Kalongo Sandra Sagboze jean Paul Cikwanine Dieudonné Sengeyi ISTM/Bukavu Anesthesia-Resuscitation Section CIMAC Hospital Center in Goma Goma The Democratic Republic of the Congo Department of Anesthesia-Resuscitation University of Lubumbashi Lubumbashi The Democratic Republic of the Congo Department of Anesthesia-Resuscitation University of Kinshasa Kinshasa The Democratic Republic of the Congo Department of Gyneco-Obstetrics University of Kinshasa Kinshasa The Democratic Republic of the Congo Anesthesia-Resuscitation Department Panzi Hospital Bukavu The Democratic Republic of the Congo

Setting: Provincial General Reference Hospital of Bukavu, General Reference Hospital of Panzi, General Reference Hospital of Ciriri, General Reference Hospital of Nyatende and Biopharm Hospital Center. Objective: Contribute to the improvement of the anesthetic ECP of patients benefiting from MVA for incomplete abortion, Describe the methodology used for adoption of the dosage formula in Anesthesia for MVA, present the mathematical demonstration leading to the dosage formula in anesthesia for MVA. Materials and Methods: Our study was descriptive by mathematical demonstration of obtaining the equilibrium constant of the dosage formula of bipuvacaine 0.1% and Fentanyl 50 µg% adapted to the weight and specific size of patients treated anesthetically in MVA cases for incomplete abortion. We also carried out an operational research by first determining the interval where our equilibrium constant is included and secondly by means of the ends of the intervals found correlated to the ends of intervals of possible weights and sizes in the being normal human female of childbearing age to arrive at the real numerical value of the equilibrium constant of the BUKAVU Dosage Formula in the case of anesthesia for MVA during the management of incomplete abortions. Results: TWO-STAGE OPERATIONAL RESEARCH: • Determination of the interval where the equilibrium constant x = −0.95 x x by crossing the means between the extremes of volumes of anesthetic drugs giving a satisfactory sensory block without hemodynamic disturbance and the extremes of normal weight and height for women of childbearing age. We ended up with X = 0.37. Conclusion: At the end of our study which had the general objectives of contributing to the improvement of the anesthetic PEC of patients receiving MVA for incomplete abortion and specific objectives of describing the methodology used for adoption of the dosage formula in Anesthesia for MVA and present the mathematical demonstration which resulted in the dosage formul

关键词： Dosage Anesthesia Intrauterine Aspiration DR Congo

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optimizing Power Flow in Northern Cameroon’s Interconnected Grid: Challenges and Solutions

引用

Journal of Power and Energy Engineering 2024年第9期12卷 63-83页

作者： jean Ndoumbe Ivan Basile Kabeina Michael Koumbou Piembe Martin Ndjock Laboratory of Computer Engineering Data Science and Artificial Intelligence National Higher Polytechnic School of Douala University of Douala Douala Cameroon Laboratory of Electronics Electrotechnics Automation and Telecommunications National Higher Polytechnic School of Douala University of Douala Douala Cameroon

This paper presents an analysis of the power flow within the Northern Interconnected Grid of Cameroon. The Newton-Raphson method has been performed, known for its accuracy, under MATLAB software, to model and solve complex power flow equations. This study simulates a series of outage scenarios to evaluate the responsiveness of the grid. The results obtained underline the crucial importance of reactive power management and highlight the urgent need to consolidate the grid infrastructure of North Cameroon. To increase grid resilience and stability, the paper recommends the strategic integration of renewables and the development of interconnections with other power grids. These measures are presented as viable solutions to meet current and future energy distribution challenges, ensuring a reliable and sustainable power supply for Cameroon.

关键词： Power Flow Northern Interconnected Grid Newton-Raphson MATLAB Grid Stability

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Healthcare Terminologies for Morbidity New Era: SNOMED and ICD11

引用

Journal of Biosciences and Medicines 2024年第8期12卷 357-368页

作者： jean Marie Rodrigues Constant Kone Michel Babri Béatrice Trombert Universit jean Monnet Saint Etienne France Felix Houphout Boigny National Polytechnic Institute Yamoussoukro Cote dIvoire

The Information Technology (IT) developments have changed the use of Healthcare terminologies from paper-based mortality statistics with the WHO international classifications of diseases (ICD) to the IT-based morbidity implementations for instance for Casemix-based healthcare funding and managing systems. This higher level of granularity is worldwide spread under the umbrella of several national modifications named ICD10 XM. These developments have met the increased use of the International Clinical Reference Terminology named SNOMED. When the updating of WHO ICD10 to WHO ICD11 was decided a merging was envisaged and a WHO SNOMED CT common work proposed a methodology to create a common formal ontology between the 11th version of the WHO International Classification of Diseases and Health Problems (ICD) and the most used in the world clinical terminology named Systematized Nomenclature of Human and Veterinary Medicine - Clinical Terms (SCT). The present work follows this unachieved work and aims to develop a SNOMED-based formal ontology for ICD11 chapter 1 using the textual definitions of ICD11 codes which is a completely new character of ICD and the ontology tools provided by SCT in the publicly available SNOMED Browser. There are two key results: the lexical alignment is complete and the ontology alignment is incomplete with the validated SNOMED concept model can be completed with not yet validated attributes and values of the SNOMED Compositional Grammar. The work opens a new era for the seamless use of both international terminologies for morbidity for instance for DRG/Casemix and clinical management use. The main limitation is that it is restricted to 1 out of 26 chapters of ICD11.

关键词： Lexical Alignment Semantic Interoperability Ontology SNOMED Concept Model ICD-11 SNOMED CT

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effect of Supplementary Irrigation on the Yield of Sorghum (Sorghum bicolor L. Moench) in the Context of Climate Change in the Dry Savannahs of Togo

引用

American Journal of Climate Change 2024年第2期13卷 163-174页

作者： Adjiwanou Atiglo-Gbenou Yaovi Ouézou Azouma jean Mianikpo Sogbedji Agricultural Mechanization and Process Engineering Research Team (ERMAP) Department of Rural Engineering and Agricultural Machinery School of Agronomy University of Lom Lom Togo Soil Climate ad Crop Sciences Interface Laboratory (LISSCPV) Department of Soil Science School of Agronomy University of Lom Lom Togo

Under the current context of climate change, supplementary irrigation may be needed for crop production resilience. We determined the effects of supplementary irrigation on sorghum grain yield in the dry Savannah region of Togo. A two-year trial was conducted in a controlled environment at AREJ, an agro-ecological center in Cinkassé. The plant material was sorghum variety Sorvato 28. The experimental design was a Completely Randomized Block with three replications and three treatments as follows: T0 control plot (rainfed conditions);T1 (supplementary irrigation from flowering to grain filling stage) and T2 (supplementary irrigation from planting to grain filling stage). Two irrigation techniques (furrow and Californian system) were used under each watering treatment. The results showed that irrigation technique significantly affected panicle length with no effect on 1000 grains mass. Panicle length and grain yields varied from 15.59 to 25.71 cm and 0.0 to 2.06 t∙h−1, respectively, with the highest values (25.66 cm and 2.06 t∙h−1, respectively) under the T2 treatment with the California system-based supplementary irrigation. The comparison of results obtained on treatment T0 and T2, shows that supplementary irrigation increased the yields by at least 68.62%. Supplementary irrigation during sowing and growing season (T2) improved sorghum yields in the dry savannahs of Togo, with a better performance of the California irrigation system.

关键词： Climate Change Supplementary Irrigation Sorghum Grain Yield Dry Savannah Togo

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：