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Prevention of Gastrointestinal Pathologies: Comparative Study of the Microbial Flora of the Sanitary Surfaces of the Toilets of Students and Staff of the Félix Houphouët-Boigny University
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作者 N’gbesso Jean-Paul N’gbesso Beudje Félicité +3 位作者 Okoubo Née A. Nicaise N’guessan Mambey Serge Juili Landry A. Arra Allou Aime Constantin Ahoua 《Open Journal of Medical Microbiology》 2020年第3期129-138,共10页
<div style="text-align:justify;"> <span style="line-height:1.5;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Pathologies transm... <div style="text-align:justify;"> <span style="line-height:1.5;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Pathologies transmissible by hand such as gastrointestinal pathologies constitute a real public health problem, especially in sub-Saharan Africa where hygienic conditions are precarious. This study took place at Félix Houphou</span><span style="white-space:nowrap;font-family:Verdana;">&#235;</span><span style="font-family:Verdana;"></span></span><span style="font-family:Verdana;">t-Boigny</span></span><span "="" style="line-height:1.5;"><span style="font-family:Verdana;"> University from April to August 2018. The samples were taken from toilet surfaces such as doorknobs, tap heads, flush push buttons and seats WC. A total of three hundred and sixty-eight (368) samples were obtained, including 170 from the staff toilets and 198 from the student toilets. The results revealed the presence of total coliforms, </span><i><span style="font-family:Verdana;">Escherichia</span></i><span style="font-family:Verdana;"> spp and </span><i><span style="font-family:Verdana;">Salmonella</span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"> spp. The surfaces of student toilets were the most contaminated surfaces. The presence of entero-bacteria on the contact surfaces of the toilets of the Félix Houphou</span><span style="white-space:nowrap;font-family:Verdana;">&#235;</span><span style="font-family:Verdana;"></span></span><span style="font-family:Verdana;">t-Boigny university represents a health risk for the university population.</span></span> </div> 展开更多
关键词 Communicable Diseases Hand HYGIENE ENTEROBACTERIACEAE TOILET UNIVERSITY
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深埋特厚煤层采动覆岩破断及裂隙场演化特征
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作者 谭毅 张少普 +11 位作者 何满潮 李辉 郭文兵 王宇 白二虎 朱淳 杨军 程浩 郭纬宇 王燃烈 曹新发 李林猫 《煤炭学报》 北大核心 2026年第2期924-942,共19页
揭示深埋特厚煤层采动覆岩破断失稳致灾机理与裂隙场演化规律,是煤矿工作面突水溃沙等灾害防治的理论基础。以陕西某矿2301工作面采矿地质条件为工程背景,基于数值模拟、分形理论、裂隙熵理论、力学模型构建及现场实测相结合的方法对采... 揭示深埋特厚煤层采动覆岩破断失稳致灾机理与裂隙场演化规律,是煤矿工作面突水溃沙等灾害防治的理论基础。以陕西某矿2301工作面采矿地质条件为工程背景,基于数值模拟、分形理论、裂隙熵理论、力学模型构建及现场实测相结合的方法对采动覆岩破断运移和裂隙场动态分布特征展开研究。从采动裂隙场角度分析了覆岩裂隙率、分形维数、裂隙长度和裂隙熵动态演化规律,揭示了各子研究区域采动过程中覆岩裂隙张开闭合裂隙占比、裂隙长度及分形演化特征,量化了覆岩裂隙空间展布的各向异性,构建了覆岩应力拱平衡轨迹方程。结果表明:采动覆岩呈现显著成组破断运移规律和裂断拱周期性起拱特征,且裂断拱周期性起拱为裂隙场主控裂隙;裂隙带内裂隙呈现“弧形”破坏分布特征,平均裂隙率及分形维数分别为2.40%与0.81,采动裂隙场演化为大部对称“拱形”拓扑结构;采动裂隙场呈现“应力场重构—裂隙萌生扩展—结构失稳重组—自修复调控”演化特征,覆岩裂隙经历了“裂隙张裂—裂隙闭合”动态演化过程,优势裂隙群通过合并机制形成贯通型裂隙网络。采用裂隙熵理论量化了裂隙场不同区域裂隙空间展布的各向异性,并统计分析了采动覆岩不同区域内裂隙倾角演化规律及分布特征;基于三铰拱结构理论,构建了采动覆岩应力拱平衡轨迹方程;通过现场实测结果分析得出导水裂隙带高度为224 m,裂采比为24.9,现场实测结果与数值模拟结果基本一致,研究结果对类似地质条件工作面相关灾害防治具有一定的参考价值。 展开更多
关键词 采动覆岩 分形理论 裂隙率 应力拱 钻孔漏失量
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固肾安胎丸联合低分子肝素钠、低剂量黄体酮治疗对先兆流产保胎妇女疗效及对凝血纤溶系统、血清炎症因子的影响
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作者 游晓霜 张利苏 +2 位作者 郑会芹 张瑞瑞 侯媛媛 《现代中医药》 2026年第2期102-108,共7页
目的探讨固肾安胎丸联合低分子肝素钠、低剂量黄体酮治疗对先兆流产保胎妇女疗效及对凝血纤溶系统、血清炎症因子的影响。方法选取2022年1月—2024年1月在我院诊治204例先兆流产保胎妇女为研究对象,应用随机数表法将其分为对照组及治疗... 目的探讨固肾安胎丸联合低分子肝素钠、低剂量黄体酮治疗对先兆流产保胎妇女疗效及对凝血纤溶系统、血清炎症因子的影响。方法选取2022年1月—2024年1月在我院诊治204例先兆流产保胎妇女为研究对象,应用随机数表法将其分为对照组及治疗组,每组102例,对照组采用低分子肝素钠、低剂量黄体酮治疗,治疗组在对照组基础上采用固肾安胎丸治疗,对比两组临床疗效、中医证候积分、激素水平、凝血纤溶系统功能、炎症因子及不良事件。结果治疗组总有效率高于对照组(P<0.05)。治疗后,两组中医证候积分均降低,且治疗组低于对照组(P<0.05)。治疗后,两组β-人绒毛膜促性腺激素(β-HCG)、孕酮(P)、雌二醇(E2)均升高,且治疗组高于对照组(P<0.05)。治疗后,两组凝血因子X(FX)活性、纤溶酶原活化剂抑制物(PAI-1)均降低,且治疗组低于对照组(P<0.05);治疗后,两组组织型纤溶酶原活化剂(t-PA)均升高,且治疗组高于对照组(P<0.05)。治疗后,两组肿瘤坏死因子α(TNF-α)、干扰素-γ(IFN-γ)均降低,且治疗组低于对照组(P<0.05)。两组不良事件发生率无统计学意义(P>0.05)。随访至妊娠28周或分娩,治疗组持续妊娠率、活产率均高于对照组(P<0.05),流产率低于对照组(P<0.05)。结论固肾安胎丸联合低分子肝素钠、低剂量黄体酮治疗先兆流产,不仅能短期缓解症状、调节凝血纤溶系统及炎症因子,还能显著提高中远期持续妊娠率与活产率,降低流产风险,安全性较高。 展开更多
关键词 固肾安胎丸 低分子肝素钠 低剂量 黄体酮 先兆流产 保胎妇女 凝血纤溶系统 炎症因子
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基于多技术协同的甲酸钠高效低耗工艺研究
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作者 陈斌 李瑞琛 谢庆国 《山西化工》 2026年第1期233-234,252,共3页
研究针对现有甲酸钠生产工艺的不足,利用公司造气炉产生的混合气体,开发新型生产工艺。通过净化混合气体、控制反应条件、采用超滤浓缩结合减压蒸发以及喷雾干燥与冷却结晶相结合的技术,制得纯度≥98%、饱和盐水密度为1.33~1.38 g/cm^(3... 研究针对现有甲酸钠生产工艺的不足,利用公司造气炉产生的混合气体,开发新型生产工艺。通过净化混合气体、控制反应条件、采用超滤浓缩结合减压蒸发以及喷雾干燥与冷却结晶相结合的技术,制得纯度≥98%、饱和盐水密度为1.33~1.38 g/cm^(3)的颗粒状甲酸钠产品。该工艺路线简单、设备操作便捷、生产成本降低15%~20%,且解决了甲酸钠易结块问题,符合环保要求,具有良好的推广应用前景,但仍存在进一步提升产品纯度、降低成本和优化设备的空间。 展开更多
关键词 甲酸钠 新工艺 一氧化碳 氢氧化钠 结晶干燥 生产成本
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环氧/氟碳防腐涂料的制备及其性能研究
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作者 李瑞琛 曹国栋 +1 位作者 陈斌 谢庆国 《山西化工》 2026年第2期22-23,共2页
以环氧树脂和氟碳树脂为主要原料,在HB175催化下固化制备环氧/氟碳自分层疏水防腐涂料。研究了该涂料的分层机理及影响性能的关键因素,通过性能测试和正交实验确定最佳配方:氟碳树脂质量占基料总量的30%~50%,环氧树脂质量占基料总量的30... 以环氧树脂和氟碳树脂为主要原料,在HB175催化下固化制备环氧/氟碳自分层疏水防腐涂料。研究了该涂料的分层机理及影响性能的关键因素,通过性能测试和正交实验确定最佳配方:氟碳树脂质量占基料总量的30%~50%,环氧树脂质量占基料总量的30%~50%,颜填料用量为3%,固化剂用量为30%。最后对该涂料的发展前景进行了展望。 展开更多
关键词 防腐 环氧树脂 氟碳树脂 自分层
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聚碳酸酯二元醇中碳酸丙烯酯检测方法的开发
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作者 高辉 何战猛 +5 位作者 冯博 张明月 潘玉鹏 周玉琢 付贵川 张保贵 《煤化工》 2026年第1期86-88,共3页
建立了一种基于高效液相色谱的聚碳酸酯二元醇中碳酸丙烯酯(PC)残留量的快速检测方法。通过对色谱条件优化,包括流动相组成、流速、柱温以及检测波长的选择,实现了聚碳酸酯二元醇中PC及杂质的高效分离与准确定量。实验表明,PC质量浓度在... 建立了一种基于高效液相色谱的聚碳酸酯二元醇中碳酸丙烯酯(PC)残留量的快速检测方法。通过对色谱条件优化,包括流动相组成、流速、柱温以及检测波长的选择,实现了聚碳酸酯二元醇中PC及杂质的高效分离与准确定量。实验表明,PC质量浓度在5 mg/50 mL~80 mg/50 mL时与峰面积线性关系良好(R^(2)>0.999),加标回收率为97.62%~99.46%,相对标准偏差(RSD)小于1%。 展开更多
关键词 碳酸丙烯酯(PC) 聚碳酸酯二元醇 高效液相色谱 色谱条件
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Investigating the influence of Fouta Jallon topography on the West African mean surface climate using RegCM5
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作者 Foungnigué SILUE Adama DIAWARA +10 位作者 Adama BAMBA Brahima KONE Arona DIEDHIOU Adjon Anderson KOUASSI Benjamin Komenan KOUASSI Fidèle YOROBA Kouakou KOUADIO Dro Touré TIEMOKO Assi Louis Martial YAPO Dianicoura Ibrahim KONE Adjoua Moise Landry FAMIEN 《Journal of Mountain Science》 2026年第2期634-646,共13页
This study uses the International Center for Theoretical Physics(ICTP)Regional Climate Model version 5(RegCM5.0)to investigate the impact of the Fouta Djallon topography on the mean surface climate of West Africa with... This study uses the International Center for Theoretical Physics(ICTP)Regional Climate Model version 5(RegCM5.0)to investigate the impact of the Fouta Djallon topography on the mean surface climate of West Africa with a focus on the June–September(JJAS)season.Two experiments were conducted:a control simulation with current topography(REF)and a sensitivity simulation with flattened terrain(FLAT).Results show that reducing the elevation leads to decreased rainfall and increased temperatures,particularly over the Guinea Coast and the modified topographic region.Rainfall decreases by approximately 4.59%in the Guinea Coast sub-zone,while it slightly increases by about 2.76%in the Sahel.The most significant rainfall reduction,exceeding 20%,occurs over the flattened area.Temperature rises across both regions,with the strongest warming over the Fouta Jallon region.This pattern is likely due to the suppression of orographic uplift,which enhances the southwesterly monsoon flow from the Atlantic Ocean and causes a northward shift of the Intertropical Convergence Zone(ITCZ)into the Sahel.The findings highlight the key role of Fouta Jallon topography on the West African climate system. 展开更多
关键词 RegCM5 TOPOGRAPHY Fouta Djallon RAINFALL West Africa
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基于实测载荷谱下的某电驱动桥桥壳结构强度及寿命分析 被引量:2
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作者 姜良兴 倪大成 +2 位作者 姚超 黄庆 卿鑫慧 《机械强度》 北大核心 2025年第2期10-18,共9页
准确地预估产品的疲劳寿命对于电动汽车关键零部件的结构强度设计以及可靠性设计具有重要作用。以实测强化路道路的载荷谱为出发点,提出了实测载荷谱数据处理与分析的方法,基于Miner准则,得出了车辆在空载、半载以及满载下的载荷数据,... 准确地预估产品的疲劳寿命对于电动汽车关键零部件的结构强度设计以及可靠性设计具有重要作用。以实测强化路道路的载荷谱为出发点,提出了实测载荷谱数据处理与分析的方法,基于Miner准则,得出了车辆在空载、半载以及满载下的载荷数据,通过时域频域处理、损伤等效处理等,得到了可供振动仿真分析以及室内台架试验的关键数据;设计开发了一款平行轴式电驱动桥,针对桥壳等关键部件开展了静力学分析和模态分析,得出了桥壳不会因为路面激励而产生扭转和弯曲现象的结论;基于nCode DesignLife仿真分析软件得出了桥壳疲劳寿命与损伤值分布,通过桥壳耐久试验验证了仿真分析的准确性;基于实测的强化路道路载荷谱,在整车振动试验台上开展了15000 km的强化路室内整车振动试验。试验表明,该电驱动桥产品整体寿命及可靠性满足设计要求,同时验证了分析方法的可靠性。 展开更多
关键词 商用车 电驱动桥 道路载荷谱 疲劳寿命 疲劳分析
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综放工作面末采深孔预注浆加固技术研究
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作者 胡黎明 王春 《煤炭与化工》 2025年第4期36-40,共5页
针对综放工作面末采期间围岩破碎、撤架通道维护困难、高分子化学浆存在安全隐患等问题,设计了末采区域无机材料深孔预注浆加固方案,在顺槽内施工130 m深孔,选择速凝早强和超细高强两种无机注浆材料,采用“0~30~130 m”分段注浆工艺,分... 针对综放工作面末采期间围岩破碎、撤架通道维护困难、高分子化学浆存在安全隐患等问题,设计了末采区域无机材料深孔预注浆加固方案,在顺槽内施工130 m深孔,选择速凝早强和超细高强两种无机注浆材料,采用“0~30~130 m”分段注浆工艺,分别进行端头加固和全长加固。工业性试验结果表明:分段注浆工艺和两种材料保证了有效注浆量,单孔最大注浆量12.6 t,注浆终止压力14 MPa,漏浆极少,工作面进入预注浆加固区域后,片帮、冒顶架次占比为3.8%,远小于未注浆条件下的56%,撤架通道维护良好,工作面安全撤架,无机材料预注浆成本仅为高分子化学浆的38.7%。 展开更多
关键词 末采 撤架通道 分段注浆 无机注浆材料 无机材料预注浆
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考虑强地下水渗流影响的地热开采综合评估
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作者 金涛 杨乐 +3 位作者 温凯 郭攀 杨金才 刘冠男 《能源与环保》 2025年第2期165-174,共10页
在常规的U型管地热开采工程中,采热管跨越地下水渗流地层,其采热效率会受到不同程度的影响。宁夏平原青铜峡库区地热储层地下水充沛,因施工、采热、基建等因素导致地下水渗流现象普遍且复杂,地热储层孔隙率有着复杂的时空非线性演化特... 在常规的U型管地热开采工程中,采热管跨越地下水渗流地层,其采热效率会受到不同程度的影响。宁夏平原青铜峡库区地热储层地下水充沛,因施工、采热、基建等因素导致地下水渗流现象普遍且复杂,地热储层孔隙率有着复杂的时空非线性演化特性。为此,提出了地应力、热传导效应及地下水压力耦合效应下的U型管地热开采模型,并采用有限元方法求解强地下水渗流特性下地热开采效率、地热储层温度及地下水压力的时空演化规律。结果表明,数值模型计算结果与实地地热开采数据吻合较好;不同地下水渗流方向对地热开采的影响显著,由下至上的地下水渗流方向对地热开采最有利;不同地热储层孔隙率对地热开采也有着较为明显的影响。对于地下水由地下向地表渗流的工况来说,更大的地热储层孔隙率有着较好的采热效率;而对于其他地下水渗流方向,更小的地热储层孔隙率更有益于地热开采。研究成果将为宁夏平原强地下水渗流背景下的地热开采提供重要的理论参考依据。 展开更多
关键词 地热储层 地下水渗流 孔隙率 多场耦合 数值模拟
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超声水表长期工作可靠性问题的解决方案综述
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作者 金传恩 《电子测量技术》 北大核心 2025年第23期144-152,共9页
本文针对当前超声水表普遍存在的长期工作稳定性与可靠性问题,首次从测量原理角度分析造成该问题的可能原因,并从测量原理、可测性设计及测试设备三方面提出新的技术方案。具体包括:首次提出基于回波衰减检测的声波飞渡时间测量原理,从... 本文针对当前超声水表普遍存在的长期工作稳定性与可靠性问题,首次从测量原理角度分析造成该问题的可能原因,并从测量原理、可测性设计及测试设备三方面提出新的技术方案。具体包括:首次提出基于回波衰减检测的声波飞渡时间测量原理,从测量原理层面彻底规避了现有基于第一回波检测的超声波渡越时间测量原理中,因水表硬件性能衰减和各类噪声导致第一回波检测错误而带来的长期工作稳定性与可靠性问题,并验证了基于回波衰减检测的测量原理的可行性;提出可测性增强的超声波流体流量测量仪表的设计方法和仪表装置;提出适用于超声波流体流量仪表的测试系统和装置,解决超声水表当前型评测试和出厂检测中“测不出、测不全、测不准”的问题。本文旨在为当前超能水表存在的长期工作稳定性与可靠性问题提供系统性技术解决方案,为以高精度为优势的超声水表进入大规模商用奠定基础。本文的问题探析、测量原理和方法、仪表可测性设计及仪表测试设备的创新技术方案同样适用于超声燃气表和超声油表等超声波流体流量计量仪表。 展开更多
关键词 声波飞渡时间测量 超声水表 长期工作稳定性与可靠性 回波衰减检测 测量精度
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老龄化背景下防跌倒可穿戴产品的开发现状与前景
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作者 黄鑫鑫 杨淋晖 赵林 《服装学报》 北大核心 2025年第5期424-430,共7页
对2013—2023年跌倒监测技术的演变及防跌倒可穿戴产品的产业化进展进行了回顾与分析。通过梳理国内外相关文献,运用Citespace可视化软件,揭示跌倒预防领域的研究热点和发展趋势。在此基础上,总结跌倒监测技术的发展历程,并分析当前市... 对2013—2023年跌倒监测技术的演变及防跌倒可穿戴产品的产业化进展进行了回顾与分析。通过梳理国内外相关文献,运用Citespace可视化软件,揭示跌倒预防领域的研究热点和发展趋势。在此基础上,总结跌倒监测技术的发展历程,并分析当前市场上典型的防跌倒产品,提出老年人防跌倒可穿戴产品未来可围绕人工智能的个性化风险预测与管理、多传感器融合与智能环境协同、柔性材料与微型化技术提升佩戴舒适性、智能化康复训练与远程医疗支持4个方面进行开发,顺应市场和老年群体的需求。 展开更多
关键词 老龄化 Citespace软件 跌倒监测 可穿戴 产品设计
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Convergence of diabetic ketoacidosis, acute pancreatitis, and malaria: A case report
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作者 Koffi Isidore Kouame Paterne Michael N'kan Mobio +7 位作者 Judith Kouesseu Bouh Jean Kouassi Konan Theodore Klinnan Coulibaly Cyrille Wallamitien Toure Lauraine Armande Assoh Diebi Jose Ndjassipli Homawoo Kouakou Bable Essuy Koffi Paul Yapo Yapo 《World Journal of Clinical Cases》 2025年第23期101-105,共5页
BACKGROUND Type 1 diabetes is an autoimmune disease leading to insulin deficiency,and it is mainly diagnosed in young adults.One of the major acute complications of type 1 diabetes is diabetic ketoacidosis(DKA),which ... BACKGROUND Type 1 diabetes is an autoimmune disease leading to insulin deficiency,and it is mainly diagnosed in young adults.One of the major acute complications of type 1 diabetes is diabetic ketoacidosis(DKA),which is a metabolic emergency that can be triggered by stress,infection,or poor blood glucose control.The association of DKA with conditions such as acute pancreatitis and malaria is rare and therefore represents a major diagnostic and therapeutic challenge.CASE SUMMARY A 20-year-old female was admitted to the emergency room for abdominal pelvic pain,fever,asthenia,polyuria,and polydipsia with a progressive deterioration of her state of consciousness.At admission,she was in a mild coma(Glasgow score:9),had a fever of 38.5°C,and had hyperglycemia(6 g/dL).The tests revealed severe DKA,hypertriglyceridemia,hyperamylasemia,and hyperlipasemia as well as malaria parasite density.The computed tomography scan confirmed acute stage E pancreatitis.The diagnosis was that of inaugural ketoacidosis of type 1 diabetes unbalanced by pancreatitis and malaria.Treatment included insulin therapy,rehydration,and antimalarial and analgesic treatment.After 10 days,the outcome was favorable with a normalization of the blood sugar,and an endocrine follow-up was recommend.CONCLUSION Rapid and multidisciplinary management of DKA,pancreatitis,and malaria led to a favorable and stable prognosis. 展开更多
关键词 Type 1 diabetes Diabetic ketoacidosis Acute pancreatitis MALARIA HYPERTRIGLYCERIDEMIA Case report
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Copula Method and Neural Networks for X-Band Polarimetric Radar Rainfall Retrieval in West Africa
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作者 Sahouarizié Adama Ouattara Eric-Pascal Zahiri +2 位作者 Kadjo Augustin Koffi Modeste Kacou Abé Delfin Ochou 《Journal of Environmental & Earth Sciences》 2025年第4期27-54,共28页
In the context of climate change,countries in West Africa are faced with recurrent flooding with catastrophic consequences,that makes it imperative to have access to rainfall information on fine spatial and temporal s... In the context of climate change,countries in West Africa are faced with recurrent flooding with catastrophic consequences,that makes it imperative to have access to rainfall information on fine spatial and temporal scales for better monitoring and prediction of these phenomena,as could be provided by weather radars.Based on an extensive archive of data from the X-band polarimetric radar and rain gauges observations gathered during the intensive AMMA campaigns in 2006–2007 and the Megha-Tropiques satellite measurement validation programme in 2010 in West Africa,we(i)simulated jointly realistic data for polarimetric radar variables and rain intensity using copula,and(ii)assessed rain rate estimation methods based on neural network(NN)inversion techniques and non-linearly calibrated parametric algorithms.The assessment of rainfall rate retrieval by these estimators is carried out using the part of the observations database not employed for calibration steps.The multiparametric algorithms R(ZH,K_(DP))and R(Z_(DR),K_(DP))perform better than R(ZH,Z_(DR))and R(ZH,Z_(DR),K_(DP)),especially since they are calibrated using copulas with upper tail dependencies,with KGE ranging in 0.68–0.75 and 0.79–0.82,respectively versus ranges of 0.40–0.64 and 0.20–0.51,for the two latter estimators.The neural network-based estimators RNN(Z_(DR),K_(DP))and RNN(ZH,K_(DP)),show KGE score characteristics comparable to those obtained from the best parametric relations,specifically optimized for the synthetic copula-based dataset.However,the neural network-based estimators were shown to be more robust when applied to a specific rainfall event.More specifically,neural network-based estimators trained on synthetic data are sensitive to the copulas’ability to capture the dependence between the variables of interest over the entire distribution of joint values.This leads to a near-cancellation of sensitivity to variability in the raindrop size distribution,as shown the coefficients of correlation near 1,especially for RNN(Z_(DR),K_(DP)),and for less extent RNN(Z_(H),K_(DP)). 展开更多
关键词 Quantitative Precipitation Estimation COPULAS Polarimetric Radar Data Multiparametric Algorithms Artificial Neural Network Non-Linear Fitting
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Toxicological and Safety Considerations of Nanocellulose-Containing Packaging Materials
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作者 Lucila M.Curi Maria C.Area Maria E.Vallejos 《Journal of Renewable Materials》 2025年第11期2109-2137,共29页
The global demand for renewable and sustainable non-petroleum-based resources is rapidly increasing.Lignocellulosic biomass is a valuable resource with broad potential for nanocellulose(NC)production.However,limited s... The global demand for renewable and sustainable non-petroleum-based resources is rapidly increasing.Lignocellulosic biomass is a valuable resource with broad potential for nanocellulose(NC)production.However,limited studies are available regarding the potential toxicological impact of NC.We provide an overview of the nanosafety implications associated mainly with nanofibrillated cellulose(CNF)and identify knowledge gaps.For this purpose,we present an analysis of the studies published from 2014 to 2025 in which the authors mention aspects related to toxicity in the context of packaging.We also analyze the main methods used for toxicity evaluations and the main studies about toxicity evaluation using different biomarkers for a broad interpretation.This comprehensive biblio-graphic review highlights the critical need for further research to elucidate the mechanisms fully underlining NC toxicity,mainly due to its nanofibrillar structure.We focus on the cellular responses across different evaluated cell types through in vitro evaluation,always within the context of the dose used,the type of material or its source,and the type of biomarkers used in the assessments.The importance of addressing safety considerations and key knowledge gaps for the responsible use of CNF derived fromlignocellulosic biomass and its bionanocomposites in food packaging is highlighted. 展开更多
关键词 Cytotoxicity studies nanofibrillated cellulose in vitro nanosafety PACKAGING TOXICITY
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强地下水渗流下岩层裂隙粗糙程度的地热开采耦合预测
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作者 韩冬 温凯 +3 位作者 叶大羽 杨乐 郭攀 杨金才 《能源与节能》 2025年第1期15-21,共7页
在地热开采过程中,若采热管跨越存在地下水渗流的热岩层,将会对管道传热及热能提取产生显著的影响。作为地下水渗流的主要通道,岩石裂隙的特性演化将显著影响水渗流的行为,继而影响采热管内流体的温度及热开采效率。然而,目前已发表的... 在地热开采过程中,若采热管跨越存在地下水渗流的热岩层,将会对管道传热及热能提取产生显著的影响。作为地下水渗流的主要通道,岩石裂隙的特性演化将显著影响水渗流的行为,继而影响采热管内流体的温度及热开采效率。然而,目前已发表的研究很少能综合探究岩石裂隙粗糙程度对地热开采的影响。因此,提出了一种针对跨越渗流岩层的全耦合地热开采模型,能够综合探究干热岩应力、地下水渗流效应、裂隙粗糙程度及管道传热效应,并提出了定量表征裂隙粗糙程度的参数h/a。结果表明:不同h/a对地层温度及管道流体温度影响显著;当h/a由0.15增加至0.30时,渗流地层水压最多减少了16.7%,地层温度最多降低了3.7℃。 展开更多
关键词 地热开采 地下水渗流 裂隙行为 裂隙粗糙度 数值模拟
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Leveraging farm heterogeneity to enhance living incomes:A gender-sensitive typology of cocoa farming systems in Côte d’Ivoire
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作者 Franziska OLLENDORF Claudia CORAL +2 位作者 Constant Yves ADOU YAO Stefan SIEBER Katharina LÖHR 《Regional Sustainability》 2025年第4期41-60,共20页
About 44%of the world’s cocoa is produced in one single country,Côte d’Ivoire.Providing this important raw material,most Ivorian cocoa farmers live in severe poverty,which,despite a multitude of sector interven... About 44%of the world’s cocoa is produced in one single country,Côte d’Ivoire.Providing this important raw material,most Ivorian cocoa farmers live in severe poverty,which,despite a multitude of sector interventions,is still widespread,affecting social and environmental sustainability in cocoa production.In this context,cocoa farmers are still often treated as a homogeneous group of small-scale producers(mainly males),resulting in interventions being conceptualized as one-size-fits-all approaches and failing to deliver support schemes that take farmers’specific conditions appropriately into account.Applying a broader typology approach that combines farm characteristics with farmers’characteristics,this study aims to delineate Ivorian cocoa farmers and their farms into specific types in order to improve advice for targeted sustainability interventions and living income(LI)potentials.Principal component analysis and hierarchical clustering analysis of a household dataset collected in 2022 in five cocoa-growing regions of Côte d’Ivoire were chosen to identify types of male-headed farms.To assure gender sensitive analysis,a female-headed farm type was created artificially.The specific characteristics of the identified types were captured using descriptive analysis.Descriptive statistics and non-parametric tests were then applied to examine the relationships between these farm types and various outcomes.Additionally,a binary logistic model was used to estimate the probability of these links in relation to variables relevant for achieving a LI.Finally,Spearman non-parametric correlation was used to identify eventual differences in the strength of relationships between key variables per farm type.Three different types of male-headed farms are identified:type 1(the most productive and diversified farms with larger size),type 2(middle-sized farms with strong focus on cash crops),and type 3(small-sized farms with a good level of diversification for self-consumption).The artificially created type 4 represents female-headed farms with the smallest size.On average,none of these farm types achieves a LI.However,type 1 shows the smallest LI gap,while type 4 is by far the worst.Our analyses reveal underlying socio-economic factors systematically disadvantaging female-headed cocoa farms,most notably limited access to land and other material assets.The key contribution of this study lies in the empirical identification of the different characteristics of farms in a given farming system,thereby identifying the need for targeted support interventions.Type-specific recommendations are made,showing pathways to provide tailored programs to farmers of different types in order to reduce their LI gaps. 展开更多
关键词 Living income Farm type Cocoa farmers Cash crops
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Distribution and human health risk assessment of cadmium,arsenic,mercury,lead,and iron in settling particles from the transboundary estuary in three rivers of Cote d’Ivoire,West Africa
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作者 Dehoule N’Guessan Fulgence Kouassi Assy Eudes Yapi +2 位作者 N’Guessan Louis Berenger Kouassi Koffi Marcellin Yao Aoua Sougo Coulibaly 《Acta Geochimica》 2025年第5期1040-1058,共19页
Pollution of transboundary rivers can result from anthropogenic activities in their watersheds.In this study,sediment traps were deployed to determine the fluxes,concentrations,and health risks associated with arsenic... Pollution of transboundary rivers can result from anthropogenic activities in their watersheds.In this study,sediment traps were deployed to determine the fluxes,concentrations,and health risks associated with arsenic,cadmium,mercury,lead,and iron in the estuaries of three transboundary rivers(Comoé,Bia,and Tanoé)in West Africa.Thus,the analysis of metal-associated sedimentation particle samples collected in rainy,flood,and dry seasons was required.Sediment traps were used to calculate the metal fluxes associated with sedimentation particles towards the Atlantic Ocean.Finally,the carcinogenic and non-carcinogenic risks of ingestion and dermal contact associated with sedimentation particles were assessed.The results showed that the total concentrations of trace metals in particulate matter were higher than in the UCC(Upper Crust Continental),with the exception of lead.The highest fluxes of lead,mercury,iron and arsenic associated with sedimented particles were observed during flood periods in the estuary of the Comoé,Bia and Tanoérivers.Cadmium fluxes associated with sedimentation particles were highest in the rainy season in the Bia and Comoéestuaries and in the flood season in the Tanoéestuary.Pearson’s correlation analysis and the enrichment factor showed that the trace metals were derived from anthropogenic activities such as mining and farming.In addition,contamination indices showed that sediment particles in the estuaries of the three rivers were severely contaminated with mercury.However,the results of potential human health risks associated with trace metals show that there is no probability of exposure of the community to harmful and carcinogenic effects through ingestion and dermal absorption of sediment particles.It is essential to integrate the information from this study into policy-and decision-making processes for better management of transboundary river water resources in coastal countries,particularly the Côte d’Ivoire. 展开更多
关键词 Trace metals Settling particles Transboundary rivers Carcinogenic and non-carcinogenic risks ESTUARY West Africa
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Development of bubble point pressure and oil formation volume factor models using pressure-volume-temperature data
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作者 Grant Charles Mwakipunda Allou KoffiFranck Kouassi +3 位作者 Mbula Ngoy Nadege Melckzedeck Michael Mgimba Mbega Ramadhani Ngata Long Yu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期7127-7146,共20页
The Pressure-Volume-Temperature(PVT)properties of crude oil are typically determined through laboratory analysis during the early phases of exploration and fielddevelopment.However,due to extensive data required,time-... The Pressure-Volume-Temperature(PVT)properties of crude oil are typically determined through laboratory analysis during the early phases of exploration and fielddevelopment.However,due to extensive data required,time-consuming nature,and high costs,laboratory methods are often not preferred.Machine learning,with its efficiencyand rapid convergence,has emerged as a promising alternative for PVT properties estimation.This study employs the modified particle swarm optimization-based group method of data handling(PSO-GMDH)to develop predictive models for estimating both the oil formation volume factor(OFVF)and bubble point pressure(P_(b)).Data from the Mpyo oil fieldin Uganda were used to create the models.The input parameters included solution gas-oil ratio(R_(s)),oil American Petroleum Institute gravity(API),specificgravity(SG),and reservoir temperature(T).The results demonstrated that PSO-GMDH outperformed backpropagation neural networks(BPNN)and radial basis function neural networks(RBFNN),achieving higher correlation coefficientsand lower prediction errors during training and testing.For OFVF prediction,PSO-GMDH yielded a correlation coefficient(R)of 0.9979(training)and 0.9876(testing),with corresponding root mean square error(RMSE)values of 0.0021 and 0.0099,and mean absolute error(MAE)values of 0.00055 and 0.00256,respectively.For P_(b)prediction,R was 0.9994(training)and 0.9876(testing),with RMSE values of 6.08 and 8.26,and MAE values of 1.35 and 2.63.The study also revealed that R_(s)significantlyimpacts OFVF and P_(b)predictions compared to other input parameters.The models followed physical laws and remained stable,demonstrating that PSO-GMDH is a robust and efficientmethod for predicting OFVF and P_(b),offering a time and cost-effective alternative. 展开更多
关键词 Oil formation volume factor Bubble point pressure Pressure-volume-temperature(PVT) PROPERTIES Machine learning
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基于多分类器的无分割手写数字字符串识别算法 被引量:3
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作者 任晓奎 丁鑫 +1 位作者 陶志勇 何欣键 《计算机应用研究》 CSCD 北大核心 2020年第7期2222-2226,共5页
手写体数字字符串识别常用于邮件自动分拣、银行票据和财务报表的录入中,针对其分割识别算法复杂度较高、准确率较低的问题,提出一种多分类器下无分割手写数字字符串识别算法。该算法的核心是采用四个分类器实现粘连字符串的无分割识别... 手写体数字字符串识别常用于邮件自动分拣、银行票据和财务报表的录入中,针对其分割识别算法复杂度较高、准确率较低的问题,提出一种多分类器下无分割手写数字字符串识别算法。该算法的核心是采用四个分类器实现粘连字符串的无分割识别;将残差结构应用于Le Net-5网络,以增加网络深度,提高识别准确率,加快收敛速度;使用动态选择策略,以避免长度分类器误分类对识别结果的影响。实验结果表明,在NIST SD19一位数字和Synthetic数据集训练网络下,使用NIST SD19上长度为2、3、4、5、6的字符串验证网络,其识别准确率分别为99.3%、98.5%、98.1%、96.6%和97.2%。 展开更多
关键词 图像处理 手写数字字符串识别 多分类器 无分割 动态选择
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