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氧对Fe(Cr，Mo)粉末冶金钢的显微组织与断口形态的影响

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粉末冶金技术 2013年第5期31卷 385-391页

作者： Lorenz S.Sigl patrice delarbre 韩凤麟 Sinterstahl GmbH 87629 Füssen

有一些粉末冶金(Cr,Mo)合金钢是由大量生产的Astaloy CrM粉末(3%Cr,0.5%Mo)制造的,并且烧结件具有不同的含氧量。对这些材料的显微组织与断口形态进行了分析。发现,氧一般是以Cr_2O_3颗粒析出,聚集在沿以前颗粒边界的平面上。这种空间形... 详细信息

有一些粉末冶金(Cr,Mo)合金钢是由大量生产的Astaloy CrM粉末(3%Cr,0.5%Mo)制造的,并且烧结件具有不同的含氧量。对这些材料的显微组织与断口形态进行了分析。发现,氧一般是以Cr_2O_3颗粒析出,聚集在沿以前颗粒边界的平面上。这种空间形相(spatial configuration)控制着烧结颈塑性变形时的晶核形成与微小孔隙的间距,因此,含氧量增高时,韧性与疲劳强度都会大大减低。最后表明,用高温烧结可制成兼具高强度与韧性好的粉末冶金(Cr,Mo)合金钢。这是因为高温烧结可将这些材料的含氧量(质量分数)减小到<0.05%。

关键词：铬钢韧性断裂性状

用常规强度试样与粉末冶金零件测定的力学性能的比较

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粉末冶金技术 2013年第3期31卷 229-234页

作者： LorenzS.Sigl patrice delarbre Ulrike Jehring 韩凤麟 Sinterstahl GmbH 87629 Füssen Germany Technical University Dresden 01217 Dresden Germany

由于零件的强度难以试验测定,因此通常都不使用这些数据。这篇论文介绍了一种可直接测定零件强度的新方法。这种方法是采用水射流切割(Water-jet Cutting),从零件上切割小型矩形试棒(尺寸约为40mm×5mm×5mm),经磨加工制备成试棒,用于... 详细信息

由于零件的强度难以试验测定,因此通常都不使用这些数据。这篇论文介绍了一种可直接测定零件强度的新方法。这种方法是采用水射流切割(Water-jet Cutting),从零件上切割小型矩形试棒(尺寸约为40mm×5mm×5mm),经磨加工制备成试棒,用于测定力学性能。这篇论文将由高合金化Fe(Mo)-Ni-Cu粉末冶金钢制造的同步器齿毂作为典型零件,用由其上切割制成的矩形试棒测定了抗拉强度、冲击强度与三点弯曲的横向断裂强度,并将其和用常规拉伸试样(DIN EN ISO 2740)测定的强度与冲击性能进行了比较。由零件试棒和常规试样测定的性能完全一致,都在试验误差范围之内。为证明比较的有效性,还通过全面的化学与显微组织鉴定,对两种试样的相似性进行了核实。采用新方法评定了生产工艺变量对同步器齿毂的力学性能的影响。建立了小拉伸试棒的横向断裂强度与抗拉强度之间的相互关系。

关键词：力学性能硬度拉伸性能横向断裂强度

Tensile strength and failure behavior of rock-mortar interfaces: Direct and indirect measurements

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 41-55页

作者： Ghasem Shams patrice Rivard Omid Moradian Civil Engineering and Building Engineering Department Universitéde SherbrookeSherbrookeQuébecCanada Department of Earth Sciences Swiss Federal Institute of Technology(ETH)ZurichSwitzerland Department of Civil and Environmental Engineering Colorado School of MinesGoldenCOUSA

The tensile strength at the rock-concrete interface is one of the crucial factors controlling the failure mechanisms of structures,such as concrete gravity *** the critical importance of the failure mechanism and tensile strength of rock-concrete interfaces,understanding of these factors remains very *** study investigated the tensile strength and fracturing processes at rock-mortar interfaces subjected to direct and indirect tensile *** image correlation(DIC)and acoustic emission(AE)techniques were used to monitor the failure mechanisms of specimens subjected to direct tension and indirect loading(Brazilian tests).The results indicated that the direct tensile strength of the rock-mortar specimens was lower than their indirect tensile strength,with a direct/indirect tensile strength ratio of 65%.DIC strain field data and moment tensor inversions(MTI)of AE events indicated that a significant number of shear microcracks occurred in the specimens subjected to the Brazilian *** presence of these shear microcracks,which require more energy to break,resulted in a higher tensile strength during the Brazilian *** contrast,microcracks were predominantly tensile in specimens subjected to direct tension,leading to a lower tensile *** monitoring of the cracking processes in the rock-mortar interfaces revealed that they show AE precursors before failure under the Brazilian test,whereas they show a minimal number of AE events before failure under direct *** to different microcracking mechanisms,specimens tested under Brazilian tests showed lower roughness with flatter fracture surfaces than those tested under direct tension with jagged and rough fracture *** results of this study shed light on better understanding the micromechanics of damage in the rock-concrete interfaces for a safer design of engineering structures.

关键词： Rock-mortar Rock-concrete Moment tensor inversion(MTI) Acoustic emission(AE) Digital image correlation(DIC) Tensile strength Direct tensile test Brazilian test

Results of Trans-Urethral Resection of Bladder (TURB) for the Treatment of Non-Infiltrating Bladder Tumors (NMIBT) in Musk in Bouake

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Open Journal of Urology 2024年第2期14卷 39-49页

作者： Kouassi patrice Avion N’diamoi Akassimadou Venance Alloka Sadia Kamara Koffi Dje Urology Department Bouaké University Hospital (CHU) Bouaké Ivory Coast

Background: bladder tumors rank 2nd among urological tumors in sub-Saharan Africa, particularly in Côte d’Ivoire. Objective: to report the results of transurethral resection of the bladder (TURB) for the treatment of non-muscle-infiltrating bladder tumors (NMIBT) in Bouaké. Patients and methods: we conducted a cross-sectional, descriptive study of transurethral resection of the bladder (TURB) for the treatment of non-muscle-infiltrating bladder tumors (NMIBT) between January 2022 and April 2023. All patients and their families were informed in advance and had signed an informed consent form. All patients with a non-muscle-invasive bladder tumor confirmed by an initial TURB were included, and patients with a bladder tumor infiltrating the bladder muscle were excluded. Diagnosis was based on cystoscopy and anatomopathological examination of resection shavings. Parameters studied were: age, sex, risk factors, reason for consultation, clinical signs, cystoscopy findings, stage, grade, Evolution. Results: 17 patients with a mean age of 53.7 years (22-73 years) underwent trans-ureteral bladder resection to treat a non-muscle-infiltrating bladder tumor (NMIBT). Male gender predominated with 88.23% (n = 15), the majority of patients came from the ME region with 47.05% (n = 8), farmers were the most numerous (52.94%;n = 9). The most frequent reason for consultation was macroscopic hematuria with 64.1% (n = 11), risk factors were dominated by urinary bilharziasis with 70.58% (n = 12), physical examination was normal in 47.05% (n = 8). Hemoglobin (HB) levels were between 7.5 and 8.5 g/dl in 52.94% (n = 9). On cystoscopy, the tumor was budding in 76.45% (n = 13), the localization was trigonal in 52.9% (n = 9) and the base of implantation was sessile in 70.52% (n = 12). On ultrasound, the tumor was 3 cm or larger in 70.52% (n = 12). Therapeutically, 82.35% (n = 14) of patients received a blood transfusion. TURB was complete in the majority of cases 88.23% (n = 15). Squamous cell

关键词： Bladder Tumor NMIBT TURB Squamous Cell Carcinoma

Transurethral Resection of the Prostate (TRUP) for the Treatment of Benign Prostatic Hyperplasia (BPH) in Central Cote D’Ivoire: Indications and Results

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Open Journal of Urology 2024年第2期14卷 27-38页

作者： Kouassi patrice Avion N’diamoi Akassimadou Venance Alloka Sadia Kamara Koffi Dje Urology Department Bouaké University Hospital Bouaké C&#244te d’Ivoire

Background: Benign prostatic hyperplasia (BPH) is defined histologically as adenomyofromatous hyperplasia of the transitional zone of the prostate. It remains the most common benign tumour in men over the age of 50, and transurethral resection of the prostate (TURP) remains the surgical treatment of choice. Objectives: To determine the indications and present our results of transurethral resection of the prostate. Patients and Methods: After obtaining approval from the ethics committee of the private hospital and the university hospital of Bouaké (Côte d’Ivoire), we conducted a cross-sectional study of transurethral resection of the prostate (TURP) to treat benign prostatic hyperplasia (BPH) between January 2021 and April 2023. All patients and their families were informed beforehand and had signed an informed consent form. All patients with benign prostatic hyperplasia (BPH) with ultrasound weight of less than 80 grams were included. The following parameters were studied: age, reason for consultation, ultrasound prostate weight of benign prostatic hyperplasia, indication for TURP, duration of operation, blood loss, duration of post-PRT urinary drainage, length of hospital stay, morbidity and mortality, and outcome. Results: 39 patients with a mean age of 58.3 years (57-77 years) underwent transurethral resection of the prostate (TURP). TURP was indicated in 46.15% (n = 18) of cases of refractory acute urinary retention with failure of the urinary catheter removal test, 17.94% (n = 7) of cases of lower urinary tract disorders that were incapacitating despite treatment, 15.38% (n = 6) of cases of refractory or recurrent urinary tract infection, 10.25% (n = 4) of cases of failure of medical treatment and 10.25% (n = 4) of cases of iterative hematuria. The mean duration of TURP was 53.68 min (48-57), the mean weight of the resected prostate was 58.7 g (35 and 83 g), blood loss was minimal in 92.30% (n = 36), the mean duration of irrigation-washing was 2. 5 days (1-3 da

关键词： BPH TURP Endo-Urology Prostate

Adherence to Physical Measures during the SARS-COV2 Pandemic by Haemodialysis Patients in a Burkina Faso Tertiary Hospital: A Cross-Sectional Survey

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Open Journal of Nephrology 2024年第3期14卷 375-385页

作者： Bonzi Y. Juste Zoehinga patrice Sourabie Oumar Kabore D. Dieudonne Hien Siebou Sawadogo Amidou Coulibaly Gerard Departement of Nephrology and Haemodialysis Yalgado Oudraogo Teaching Hospital Ouagadougou Burkina Faso Health Sciences Training and Research Unit Joseph KI-ZERBO University Departement of Nephrology and Haemodialysis Ouahigouya Regional Teaching Hospital Ouahigouya Burkina Faso Departement of Psychiatry Souro Sanou Teaching Hospital Bobo Dioulasso Burkina Faso Departement of Medical Oncology Yalgado Oudraogo Teaching Hospital Ouagadougou Burkina Faso Health Sciences Training and Research Unit of Lda Bernard Oudraogo University Ouahigouya Burkina Faso

Context: COVID-19 can spread rapidly in haemodialysis centres, leading to fatal outcomes. Implementing physical measures is crucial in limiting the spread of infection. Aims: To assess adherence to physical measures against SARS-Cov2 in haemodialysis patients. Methods and Material: From 13 to 19 July 2021, we administered the questionnaire to haemodialysis patients during or immediately after the dialysis session. The dependent variables were adherence to wearing masks, hand washing outside the dialysis centre, social distancing of at least 1.5 meters, and cough and sneeze hygiene. Statistical Analysis Used: Data were analyzed using Epi info software;descriptive statistics were presented as mean, headcount, and percentage;related factors were determined by multi-logistic regression. The significance level was 5%. The Health Research Ethics Committee approved the research protocol. Results: 142 patients were included (mean age: 42.5 ± 14 years). Wearing masks, hand-washing, social distancing, and coughing and sneezing hygiene were observed by 88%, 75%, 47%, and 60% of patients, respectively. Conclusion: Wearing masks was the most respected physical measure, while social distancing was the least respected.

关键词： Physical Measures COVID-19 Haemodialysis SARS-COV2 Tertiary Hospital Sub-Saharan Africa

Accumulation of Heavy Metals in Maga-Pouss Rice Fields (Far-North Region, Cameroon) and Transfer to Rice Grains

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Agricultural Sciences 2024年第3期15卷 311-326页

作者： Diane Madomguia Gilbert Bello Basokdou Kalieu W. Appoline Isabelle patrice Kuitekam Dongo Edouard Nya Serge Hubert Zebaze Togouet Department of Hydraulics and Water Management National Advanced School of Engineering University of Maroua Maroua Cameroon Research Center of Global Studies with Multidisciplinary Units (CREGUM) Maroua Cameroon National Laboratory of Analysis of Agricultural Inputs and Products Ministry of Agriculture and Rural Development Messa-Yaoundé Cameroon Department of Animal Physiology and Biology Faculty of Sciences University of Yaoundé I Yaoundé Cameroon

Monitoring of heavy metals contamination of agricultural products and their transfer and bioaccumulation in crops like rice has become a hot topic worldwide over the last two decades. The present study was carried out to determine the accumulation of heavy metals in rice fields and their transfer to rice grains. Soil, irrigation water and rice grains samples were gathered in Maga-Pouss, Far-North, Cameroon. Concentrations of six heavy metals (lead, cadmium, zinc, copper, iron and mercury) were evaluated by Atomic Absorption Spectrophotometer (AAS). Mercury was not detected in this study. Average concentrations of metals were in this order (in mg/kg): Fe (188.60 ± 97.06) > Pb (63.63 ± 7.11) > Cd (2.59 ± 0.29) > Zn (1.10 ± 1.05) > Cu (0.80 ± 0.73) in water and Pb (105.50 ± 31.11) > Fe (105.50 ± 31.11) > Cu (45.93 ± 14.39) > Zn (22.52 ± 6.40) > Cd (3.15 ± 0.49) in soil. Water in Maga-Pouss rice fields appears to be more harmful than the soil, notably for lead, cadmium and copper. In rice grains, heavy metals were found in this order (mg/kg): Fe (188.01 ± 82.62) > Cu (27.20 ± 0.00) > Zn (23.61 ± 12.42) > Pb (19.50 ± 19.91) > Cd (2.02 ± 1.05). The mean bioconcentration factor (BCF) of metals from soil to rice grains was in the following order: Fe (2.60) > Zn (1.05) > Cd (0.64) > Cu (0.59) > Pb (0.18). From water to rice grains, the order is: Cu (37.26) > Zn (22.49) > Cd (6.97) > Pb (2.74) > Fe (1.94). Rice field pH and electrical conductivity favored the uptake of lead, copper and cadmium by rice grains. The findings of this study will be good documentation for risk assessment, and decision-making by environmental managers in this region.

关键词： Heavy Metals Rice Field Bioconcenration Factor Maga-Pouss Accumulation

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

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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

Cholinesterase Activity as an Indicator of Health Risks among Kou Valley Farmers

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Journal of Biosciences and Medicines 2024年第7期12卷 71-86页

作者： Thiombiano Cherileila Hien S. Aristide Koevi Nadège Bayili Bazoma Ouattara Abdoulaye Traore patrice Traore T. Isidore Hien Herve Centre Muraz Institut National de Sant Publique (INSP) Bobo-Dioulasso Burkina Faso Institut Suprieur des Science de la Sant (INSSA) University of Nazi Boni Bobo-Dioulasso Burkina Faso Institut de Recherche en Science de la Sant (IRSS) Centre National de Recherche Scientifique et Technologique (CNRST) Ouagadougou Burkina Faso

Introduction: Pesticides are currently an essential component of agricultural production techniques for controlling pests and weeds. In Burkina Faso, non-compliance with good practice in the use of pesticides poses a real health problem for the population. This study examines the health risks associated with pesticide management in rice-growing areas. Material and Methods: A field survey was conducted in Bama, involving farmers, focusing on their socio-demographic characteristics, pesticide usage, and health effects. Cholinesterase levels were measured in subsample of farmers using a portable device. Data were analysed using Microsoft Excel, calculating means and percentages for various practices. Health consultations, protection methods, and pesticide management were studied. Erythrocyte acetylcholinesterase activity was compared before and after treatment. Data were categorised into classes based on inhibition levels, and correlation analyses determined relationships between variables such as age, years of experience, and cholinesterase activity. Results: The results indicate that rice cultivation is mainly carried out by a fairly young population, with nearly 63% being under the age of 50. Common poor practices in pesticide use include improper storage and reuse of leftover pesticides. Seven types of pesticides were identified, including organophosphates such as glyphosate, which was used in 26.7% of cases. This organophosphate has resulted in class B poisoning, causing a 30% - 50% reduction in erythrocyte cholinesterase activity. The health effects of pesticide use are felt by agricultural farmers through various symptoms of poisoning. Conclusion: To reduce the occurrence of pesticide poisoning, it is essential to launch information and awareness campaigns among the population and farmers to promote safe practices in pesticide use in Bama, Burkina Faso.

关键词： Pesticides Environmental Sanitary Risk Acetylcholinesterase Farmers Bama Burkina Faso