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Basic Characteristics of an Appropriate Waste Fillers for Solvent Free and Water-Borne Industrial Polymer Floors and Their Utilization
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作者 Jana Kosikova 《Journal of Civil Engineering and Architecture》 2024年第3期141-147,共7页
Recently the manufacture of epoxy coating and flooring materials begun to be under strong pressure to use more environmentally friendly raw materials in its composition.First tendency to reduce of solvents and diluent... Recently the manufacture of epoxy coating and flooring materials begun to be under strong pressure to use more environmentally friendly raw materials in its composition.First tendency to reduce of solvents and diluents contained in the materials appeared at the end of 90´s.This situation was supported by the Council of Europe in 2004 to reduce VOC emissions to zero till 2020.Solvent materials were thus largely replaced by solvent free materials from which the volatile substances are not released into the air.But pressure continued to increase,and over the past decade began to take centre stage water-based epoxy.On the Czech market solvent based material is still occasionally used,but predominant are solvent free materials.There are no commonly used materials containing wastes as fillers in new water-borne and solvent-free epoxy materials.Characteristics identification of the waste material as a potential filler is a set of properties that determine the limits of secondary raw materials or waste as a filler.This paper describes the basic characteristics which must be selected to meet the requirements,to affect negatively the workability,sedimentation,properties and behavior of the final floor system.Some materials must comply with special requirements,such as resistance to chemicals,etc.Next part of paper talks about utilization of polymer floors and their mechanical properties. 展开更多
关键词 Industrial polymer flooring materials waster fillers building materials
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Minimally invasive techniques for lateral maxillary sinus floor elevation: small lateral window and one-stage surgery—a 2–5-year retrospective study
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作者 Shaojingya Gao Yao Jiang +2 位作者 Yangxue Yao Songhang Li Xiaoxiao Cai 《International Journal of Oral Science》 SCIE CAS CSCD 2023年第3期401-410,共10页
This study aimed to introduce a minimally invasive technique for maxillary sinus floor elevation using the lateral approach(lSFE)and to determine the factors that influence the stability of the grafted area in the sin... This study aimed to introduce a minimally invasive technique for maxillary sinus floor elevation using the lateral approach(lSFE)and to determine the factors that influence the stability of the grafted area in the sinus cavity.Thirty patients(30 implants)treated with lSFE using minimally invasive techniques from 2015 to 2019 were included in the study.Five aspects of the implant(central,mesial,distal,buccal,and palatal bone heights[BHs])were measured using cone-beam computed tomography(CBCT)before implant surgery,immediately after surgery(T0),6 months after surgery(T1),and at the last follow-up visit(T2).Patients’characteristics were collected.A small bone window(height,(4.40±0.74)mm;length,(6.26±1.03)mm)was prepared.No implant failed during the follow-up period(3.67±1.75)years.Three of the 30 implants exhibited perforations.Changes in BH of the five aspects of implants showed strong correlations with each other and BH decreased dramatically before second-stage surgery.Residual bone height(RBH)did not significantly influence BH changes,whereas smoking status and type of bone graft materials were the potentially influential factors.During the approximate three-year observation period,lSFE with a minimally invasive technique demonstrated high implant survival rate and limited bone reduction in grafted area.In conclusion,lSFE using minimally invasive techniques was a viable treatment option.Patients who were nonsmokers and whose sinus cavity was filled with deproteinized bovine bone mineral(DBBM)had significantly limited bone resorption in grafted area. 展开更多
关键词 SURGERY viable floor
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Maxillary sinus floor augmentation: a review of current evidence on anatomical factors and a decision tree
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作者 Mingyue Lyu Dingyi Xu +1 位作者 Xiaohan Zhang Quan Yuan 《International Journal of Oral Science》 SCIE CAS CSCD 2023年第3期347-354,共8页
Maxillary sinus floor augmentation using lateral window and crestal technique is considered as predictable methods to increase the residual bone height;however,this surgery is commonly complicated by Schneiderian memb... Maxillary sinus floor augmentation using lateral window and crestal technique is considered as predictable methods to increase the residual bone height;however,this surgery is commonly complicated by Schneiderian membrane perforation,which is closely related to anatomical factors.This article aimed to assess anatomical factors on successful augmentation procedures.After review of the current evidence on sinus augmentation techniques,anatomical factors related to the stretching potential of Schneiderian membrane were assessed and a decision tree for the rational choice of surgical approaches was proposed.Schneiderian membrane perforation might occur when local tension exceeds its stretching potential,which is closely related to anatomical variations of the maxillary sinus.Choice of a surgical approach and clinical outcomes are influenced by the stretching potential of Schneiderian membrane.In addition to the residual bone height,clinicians should also consider the stretching potential affected by the membrane health condition,the contours of the maxillary sinus,and the presence of antral septa when evaluating the choice of surgical approaches and clinical outcomes. 展开更多
关键词 STRETCHING floor TREE
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Experimental Mode and Vibration Comfort Analysis of High-Rise Glulam Building Floor Structure
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作者 Yuhang He Rongzhuo Zhang +1 位作者 Yifan Zhang Zheng Wang 《Journal of Renewable Materials》 SCIE EI 2023年第6期2729-2743,共15页
In order to better meet the objective requirements of the use safety of the high-rise glulam building floor structure and the living comfort of the residents,the transient excitation,environmental excitation and frequ... In order to better meet the objective requirements of the use safety of the high-rise glulam building floor structure and the living comfort of the residents,the transient excitation,environmental excitation and frequency spectrum identification methods were used to carry out experimental modal test in-site on the three rooms numbered A,B and C of the same glulam structural building.The three rooms have different functions,different floor sizes and different floor supporting structures.The research results have shown that the first-order bending frequency of the floor structure of Room A is 27.50 Hz,the transverse second-order bending frequency is 34.75 Hz,the longitudinal second-order bending frequency is 53.25 Hz,and the first-order torsional frequency is 56.25 Hz.The reinforced wooden beam at the bottom of the floor of Room A increases the transverse stiffness of the floor structure,but does not offset the anisotropy caused by the longitudinally installed glulam floors.The fundamental frequency values of the floor structures of the three rooms numbered A,B,and C are 27.5,13 and 18 Hz,respectively.This has a relatively high innovation and reference significance for integrating the theory of structural dynamic characteristics with the dynamic testing technology,improving the design level of high-rise glulam structure buildings,and improving the living comfort of residents. 展开更多
关键词 Glulam building wooden floor experimental mode vibration comfort fundamental frequency
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Reporting Children’s Development below the Test Floor: Looking Back and Forth to Describe Individual Strengths and Needs
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作者 Elizabeth M. Green Louise A. Stroud 《Health》 CAS 2023年第2期122-133,共12页
The test floor effects seen in standardised tests lead to a standardised score of 1 or less with a flat profile that hides a child’s individual strengths and needs. The Griffiths III community of practitioners reques... The test floor effects seen in standardised tests lead to a standardised score of 1 or less with a flat profile that hides a child’s individual strengths and needs. The Griffiths III community of practitioners requested advice on the reporting of children’s development below the floor of the test, so that individual strengths and needs can be described. This paper reports the third phase of research following an earlier Scoping Review and a wider literature review. To confirm quality control, Phase 3 was conducted in a retrospective manner using the same methodology as the earlier phases but in a reverse direction. Peer reviewer comments and key elements from the Scoping Review and keywords from the publications were tabulated. Data analysis included a change of perspective to that of the child and their individual rights with respect to the literature themes already described in Phase 2. These confirmed that there is little specific guidance in the literature, but that computational advances for homogeneous populations and especially disaggregated data offer some solutions. A greater balance between broad biopsychosocial models and standardised models of assessment should be sought by practitioners together with the use of disaggregated data to highlight issues that pertain to individual subsets of results. This will ensure that the child’s right for their individual strengths and needs to be described together with a plan for management, may be met. 展开更多
关键词 Developmental Assessment Children with Severe Disability Disaggregated Data Pattern and Needs Identification Below Test floor
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Effects of High Risk Pregnancy Factors on Pelvic Floor Muscle Weakness and Changes of PG, ACTH and CRP
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作者 Yu Han Haiyan Lin +6 位作者 Jiu Du Lianfang Chen Xianmei Wei Peijia Wei Biyun Zhou Xiangli Feng Siran Chen 《Open Journal of Obstetrics and Gynecology》 2023年第9期1569-1579,共11页
Objective: To investigate the effects of different delivery modes on perinatal pelvic floor muscle strength, PG, ACTH and CRP of high-risk pregnant women. Methods: 380 high-risk pregnant women who gave birth in our ho... Objective: To investigate the effects of different delivery modes on perinatal pelvic floor muscle strength, PG, ACTH and CRP of high-risk pregnant women. Methods: 380 high-risk pregnant women who gave birth in our hospital from March 2021 to February 2022 were selected as subjects, including 100 vaginal natural delivery, 156 forceps assisted delivery and 124 cesarean section. Pelvic floor pressure, PG, ACTH, CRP, IL-6, TNF-α and IL-4, IL-10 levels were evaluated and compared. The perinatal occurrence of pelvic floor functional disease (PFD) in high-risk pregnant women in each group was analyzed and evaluated. Results: There were statistical differences in the amount of postpartum blood loss (P 0.0001, F = 99.01), postpartum blood loss 24 h (P = 0.0004, F = 19.54) and hospital stay (P 0.0001, F = 70.81) among the three groups of high-risk women in natural vaginal delivery, forceps delivery and cesarean section. In addition, there were 72, 134 and 70 cases of abnormal pelvic floor fatigue in natural vaginal delivery, forceps assisted delivery and cesarean section (P 0.0001, χ<sup>2</sup> = 30.16). There were 36, 79 and 21 cases of muscle injury, respectively (P 0.0001, χ<sup>2</sup> = 34.16). There were 49, 98 and 43 cases of dysmuscular contraction, respectively (P 0.0001, χ<sup>2</sup> = 21.94). There were 65, 120 and 41 cases with vaginal dynamic pressure 80 cm H<sub>2</sub>O (P 0.0001, χ<sup>2</sup> = 56.86), respectively. The. 展开更多
关键词 High-Risk Pregnant Women Pelvic floor Muscle Strength Stress Response Inflammatory Response
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Two Cases of Epidermoid Cyst of the Buccal Floor Simulating: A Tumour of the Submandibular Gland
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作者 Aminata Mbaye Ndeye Fatou Thiam +3 位作者 Ababacar Diegane Faye Mouminatou Seye Houra Ahmed Cire Ndiaye 《International Journal of Otolaryngology and Head & Neck Surgery》 2023年第5期301-308,共8页
Dermoid cyst of the oral floor is rare benign tumour, who having three histological aspects: dermoid, teratoid and epidermoid. This one is characterized by the presence of a squamous stratified epithelium with cutaneo... Dermoid cyst of the oral floor is rare benign tumour, who having three histological aspects: dermoid, teratoid and epidermoid. This one is characterized by the presence of a squamous stratified epithelium with cutaneous remnants. It may occur in any part of the body, however their frequency in the ENT sphere is relatively scarce. Seven per cent (7%) only of epidermoid cysts occur in the cervico-facial area, 1.6% of which locate at the floor level. When they are located submandibular, they can pose diagnostic difficulties and look like a tumour of the submaxillary gland. We report two cases of epidermoid cyst of the floor. Both patients suffered from swelling of the submandibular gland. Magnetic Resonance Imaging was not requested due to lack of resources. However, surgery allowed in both cases the excision of a cyst next to a normal submandibular gland. Patients did well post operatively. 展开更多
关键词 Epidermoid Cyst Mouth floor Submandibular Gland SURGERY TUMOUR
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二维盆底超声评估盆膈裂孔前后径与盆腔器官脱垂的关系
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作者 刘丹 赵白桦 文烈明 《中国医学影像学杂志》 CSCD 北大核心 2024年第2期157-161,共5页
目的研究盆底正中矢状切面盆膈裂孔前后径(AP)与盆腔器官脱垂(POP)程度的关系。资料与方法回顾性收集2017年7月—2019年5月中南大学湘雅二医院262例女性的临床资料和经会阴盆底超声(TPUS)数据。在盆底正中矢状切面于最大Valsalva动作下... 目的研究盆底正中矢状切面盆膈裂孔前后径(AP)与盆腔器官脱垂(POP)程度的关系。资料与方法回顾性收集2017年7月—2019年5月中南大学湘雅二医院262例女性的临床资料和经会阴盆底超声(TPUS)数据。在盆底正中矢状切面于最大Valsalva动作下测量AP,通过TPUS和盆腔器官脱垂量化系统(POP-Q)测定POP程度,并分析AP与POP程度的关系,采用受试者工作特征曲线分析AP对POP程度的预测能力。结果共获得237例有效数据,其中POP-Q 0度POP 51例(21.51%),I度57例(24.05%),II度49例(20.67%),III度44例(18.56%),IV度36例(15.18%)。AP为37.10~97.90 mm,平均(61.33±10.71)mm。在TPUS或POP-Q系统诊断的不同程度POP中,AP测值差异均有统计学意义(F=52.00、58.18,P均<0.01)。以AP=6.0 cm为截断值,预测TPUS明显POP的敏感度为81.0%,特异度为75.5%;预测POP-Q II度以上POP的敏感度为74.5%,特异度为76.0%。AP与POP严重程度呈正相关,AP<6.0 cm与0~I度POP相关,6.0 cm≤AP<6.5 cm与II度POP相关,6.5 cm≤AP<7.0 cm与II~III度POP相关,7.0 cm≤AP与IV度POP相关(r=0.61、0.47、0.56、0.41,P均<0.05)。结论AP≥6.0 cm提示盆膈裂孔扩张,可能发生POP;AP越大,器官脱垂程度越严重。 展开更多
关键词 盆腔器官脱垂 女性 盆膈裂孔 超声检查 盆底
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经会阴盆底超声参数对盆底功能障碍性疾病的监测效果及对盆底康复治疗的指导价值
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作者 李静 刘瑞明 +4 位作者 王文荣 朱媛 李仰懿 彭娜娜 杨振冬 《中国性科学》 2024年第1期62-66,共5页
目的探究经会阴盆底超声参数对盆底功能障碍性疾病(PFD)的监测效果及对盆底康复治疗的指导价值。方法选取2021年1月至2022年6月江苏省连云港市妇幼保健院119例产后42 d发现的PFD患者作为研究对象,根据分娩情况分为初产妇组(n=59)和经产... 目的探究经会阴盆底超声参数对盆底功能障碍性疾病(PFD)的监测效果及对盆底康复治疗的指导价值。方法选取2021年1月至2022年6月江苏省连云港市妇幼保健院119例产后42 d发现的PFD患者作为研究对象,根据分娩情况分为初产妇组(n=59)和经产妇组(n=60)。比较两组及不同分娩方式患者盆底超声参数,所有患者均行盆底康复治疗,治疗1个月后统计疗效,分析各参数预测疗效的价值。结果经产妇组尿道旋转角、膀胱后角、膀胱移动度、肛提肌裂孔面积(最大Valsalva动作)均高于初产妇组(P<0.05);两组中自然分娩孕妇尿道旋转角、膀胱后角、膀胱移动度、肛提肌裂孔面积(最大Valsalva动作)均高于剖宫产孕妇(P<0.05);疗效不佳的PFD患者治疗前的尿道旋转角、膀胱后角、膀胱移动度、肛提肌裂孔面积(最大Valsalva动作)均高于疗效良好的患者(P<0.05)。治疗前尿道旋转角、膀胱后角、膀胱移动度、肛提肌裂孔面积(最大Valsalva动作)预测PFD患者盆底康复疗效不佳的曲线下面积(AUC)分别为0.821、0.771、0.732、0.703。结论经会阴盆底超声参数可监测PFD病情,且能为临床预测盆底康复疗效、判断疾病转归提供参考。 展开更多
关键词 盆底功能障碍性疾病 超声 剖宫产 自然分娩 盆底康复治疗
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女性盆底功能障碍性疾病诊治流程及物理治疗康复临床应用——康复流程、原则及智能诊疗
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作者 刘晓芳 蒋玉梅 +3 位作者 黄怀彬 徐涛 杨瑞嘉 陆叶 《生殖医学杂志》 CAS 2024年第5期569-576,共8页
女性盆底功能障碍性疾病(FPFD)发生机制复杂,专科的临床医师往往无法覆盖妇产、泌尿、肛肠、影像等各专科全面的医学专业信息,限制了对于该疾病的系统、全面诊治。FPFD的治疗需要遵循康复流程,制定个性化物理治疗干预措施,同时结合其他... 女性盆底功能障碍性疾病(FPFD)发生机制复杂,专科的临床医师往往无法覆盖妇产、泌尿、肛肠、影像等各专科全面的医学专业信息,限制了对于该疾病的系统、全面诊治。FPFD的治疗需要遵循康复流程,制定个性化物理治疗干预措施,同时结合其他方式制定综合性治疗策略。人工智能在盆底领域的应用,不仅可以提高医生诊断效率,还可以为综合治疗方案的制定提供参考和依据,实现智能诊疗与精准医疗。本文从FPFD康复流程出发,分析康复原则及内容,探究人工智能在FPFD诊疗中的应用现状,旨在为实现盆底疾病智能诊疗提供参考。 展开更多
关键词 女性盆底功能障碍性疾病 康复流程 康复原则 智能诊疗
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基于主量元素地球化学的岩屑层位源解析
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作者 桂和荣 李俊 +8 位作者 陈永青 余浩 王浩 叶爽 陈大星 梁展 胡洋 郭艳 许继影 《煤炭学报》 EI CAS CSCD 北大核心 2024年第2期929-940,共12页
近年来,岩屑录井在“华北型”煤田底板灰岩层注浆加固工程中发挥了重要作用。然而,现有的岩屑录井仅停留在颜色、颗粒大小及形貌特征等物理指标的识别上,难以精准判层,钻孔设计“顺层率”难以保障,制约着底板灰岩水害区域治理效果。基... 近年来,岩屑录井在“华北型”煤田底板灰岩层注浆加固工程中发挥了重要作用。然而,现有的岩屑录井仅停留在颜色、颗粒大小及形貌特征等物理指标的识别上,难以精准判层,钻孔设计“顺层率”难以保障,制约着底板灰岩水害区域治理效果。基于石炭纪太原组薄层灰岩及其碎屑岩夹层的元素地球化学差异特点,选取淮北煤田桃园煤矿为研究区,对太原组上段薄层灰岩L_(1)灰~L_(4)灰地层(注浆治理目的层为L_(3)灰)垂直钻孔岩心进行取样,利用X射线荧光光谱仪(XRF)定量测定了薄层灰岩及其夹层的主量元素背景值,通过聚类分析、因子分析等数理统计手段建立薄层灰岩主量元素地球化学识别模式;同时对地面定向钻水平分支孔岩屑同样开展主量元素测试,并基于已建立的地球化学识别模式进行岩屑层位源解析以及识别模式验证。结果显示:高CaO丰度、烧失量(LOI)可以作为注浆加固改造目的层L_(3)灰的特征指标,MgO(0.5%±)、MnO(0.03%±)、P_(2)O_(5)(0.08%±)丰度可作为注浆目的层上覆标志层J3的识别指标;聚类分析识别模式可有效区分太原组一灰~三灰(L_(1)灰~L_(3)灰);以元素因子得分建立的识别模式可以将太原组碎屑岩夹层与薄层灰岩进行有效区分;以岩样地球化学背景值运行判别模型得到的Fisher判别方程对注浆目的层L_(3)灰岩屑来源解析的准确率为100%。基于上述认识,论证了以确保设计“顺层率”为目标的水平分支孔岩屑地球化学源解析方法应用之可行性,进而提出了一种地面定向钻“顺层率”控制技术方案。本研究基于元素地球化学理论,对地面定向钻岩屑携带的特征地球化学信息进行了目的层层位辨识,在现场快速定量测试技术手段的支持下,可为解决华北型煤田底板灰岩水害区域注浆改造顺层难题提供了新的思路。 展开更多
关键词 主量元素丰度 地球化学识别模式 顺层率 太原组薄层灰岩 底板灰岩水害区域治理
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盆底肌训练在直肠癌患者保肛术后低位前切除综合征中的应用研究进展
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作者 徐静 蔡小凤 +1 位作者 陈萍萍 赵惠英 《中国护理管理》 CSCD 北大核心 2024年第1期134-138,共5页
盆底肌训练在直肠癌患者低位前切除综合征的预防和治疗中取得了初步效果。文章对盆底肌训练在直肠癌患者保肛术后低位前切除综合征中应用的现状及影响因素和现有研究的不足及展望等进行综述,以期为直肠癌患者盆底肌训练方案的实施提供... 盆底肌训练在直肠癌患者低位前切除综合征的预防和治疗中取得了初步效果。文章对盆底肌训练在直肠癌患者保肛术后低位前切除综合征中应用的现状及影响因素和现有研究的不足及展望等进行综述,以期为直肠癌患者盆底肌训练方案的实施提供实践参考。 展开更多
关键词 盆底肌训练 低位前切除综合征 直肠癌
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术前量化排尿训练联合术后盆底肌电刺激在前列腺癌根治术患者中的应用
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作者 徐静 宋思霖 许露伟 《中国医药导报》 CAS 2024年第3期175-178,共4页
目的 探讨术前量化排尿训练联合术后盆底肌电刺激对前列腺癌根治术患者的影响。方法 前瞻性纳入南京市第一医院2019年9月至2022年9月拟行前列腺癌根治术治疗的100例患者,以随机数字表法将其分为对照组与观察组,各50例。对照组接受术前... 目的 探讨术前量化排尿训练联合术后盆底肌电刺激对前列腺癌根治术患者的影响。方法 前瞻性纳入南京市第一医院2019年9月至2022年9月拟行前列腺癌根治术治疗的100例患者,以随机数字表法将其分为对照组与观察组,各50例。对照组接受术前常规护理与术后盆底肌电刺激,观察组在此基础上给予术前量化排尿训练。比较两组干预前后尿流动力学及排尿情况,并观察尿管拔除后24 h内及术后3个月排尿障碍发生情况。结果 干预后,两组膀胱容量、膀胱逼尿肌压力、尿流率、排尿间隔时间、每次尿量均高于干预前,且观察组高于对照组,差异有统计学意义(P<0.05);干预后,两组夜尿次数均少于干预前,且观察组少于对照组,差异有统计学意义(P<0.05);观察组尿管拔除后24 h内、术后3个月排尿障碍发生率均低于对照组,差异有统计学意义(P<0.05)。结论 应用术前量化排尿训练联合术后盆底肌电刺激可改善前列腺癌根治术后患者膀胱功能,提高排尿及控尿能力,降低排尿障碍发生率。 展开更多
关键词 前列腺癌 量化排尿训练 盆底肌电刺激 排尿障碍
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深部矿井软底回采巷道底鼓机理及防治研究
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作者 张杰 王力 +2 位作者 杨涛 何义峰 高守世 《煤炭技术》 CAS 2024年第4期12-17,共6页
针对山阳煤矿软底回采巷道严重底鼓的难题,采用理论分析、数值模拟和现场应用的方法,基于塑性理论建立了巷道底板岩体滑移线底鼓力学模型。研究表明,巷道底板破坏岩体主要分为3个区,分别为主动极限区、过渡区和被动极限区,推导了巷道底... 针对山阳煤矿软底回采巷道严重底鼓的难题,采用理论分析、数值模拟和现场应用的方法,基于塑性理论建立了巷道底板岩体滑移线底鼓力学模型。研究表明,巷道底板破坏岩体主要分为3个区,分别为主动极限区、过渡区和被动极限区,推导了巷道底板岩体的最大破坏深度,提出了锚索+卸压槽联合控制底鼓的方法。采用数值模拟的方法验证了联合控制方案的可行性,现场应用效果表明该方法能够有效控制软底巷道底鼓,为相似地质条件底鼓问题的研究提供了一定的帮助。 展开更多
关键词 底鼓机理 软底巷道 滑移线理论 联合控制
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RC框架梁端负弯矩纵筋部分置于梁侧楼板对性能的影响及构造问题分析
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作者 郑宏宇 黄林普 +2 位作者 柯晓军 许成浩 范博文 《建筑结构》 北大核心 2024年第6期74-77,31,共5页
为适应建筑多功能、大跨度、重荷载、高抗震的发展要求,框架梁端部负弯矩纵筋配筋率通常较高,节点区钢筋过于密集,混凝土施工质量不易保证,对结构综合性能有不利影响。先对梁端负弯矩纵筋部分设置于梁侧楼板内(简称APNRFS)的布筋方式进... 为适应建筑多功能、大跨度、重荷载、高抗震的发展要求,框架梁端部负弯矩纵筋配筋率通常较高,节点区钢筋过于密集,混凝土施工质量不易保证,对结构综合性能有不利影响。先对梁端负弯矩纵筋部分设置于梁侧楼板内(简称APNRFS)的布筋方式进行阐述,然后基于试验结果分析探讨了该配筋方式对结构性能带来的变化及相关构造问题。研究表明:梁端采用APNRFS布筋方式一般不会降低框架梁的承载力;梁端的弯曲变形能力和结构抗震性能有一定提高;移至板内的梁负筋布置宽度宜小于有效翼缘宽度范围;移至板内的梁端负筋宜同时兼作楼板负筋;横向分布筋参与受力,设计中应适当增配。 展开更多
关键词 钢筋混凝土 框架梁 负弯矩纵筋 楼板 钢筋布置 剪力滞
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新疆克州地区学校建筑供暖系统设计研究
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作者 秦振春 魏霖 +2 位作者 顾锡莲 袁小清 吕禧星 《工程建设与设计》 2024年第1期74-76,共3页
研究了新疆克州地区某中学供暖系统设计的思路和流程,包括热源的选择、供暖系统设计,换热站设计等,深入探讨和分析了调试过程中出现的问题,对设计和施工阶段需要关注的设计调研、施工规范等关键环节进行了总结与反思,并提出了解决方案。
关键词 区域锅炉房 热负荷 干式地暖 湿式地暖
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盆底超声评估妊娠、分娩和盆底肌锻炼对产妇盆底功能的影响
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作者 刘春节 赵改萍 李慧 《临床医学工程》 2024年第1期15-16,共2页
目的探讨盆底超声评估妊娠、分娩和盆底肌锻炼对产妇盆底功能的影响。方法选择2019年1月至2023年1月我院收治的104例产妇,根据干预方式不同分为对照组(n=50)和研究组(n=54)。对照组给予常规妊娠指导和护理,研究组则在妊娠28周后加用盆... 目的探讨盆底超声评估妊娠、分娩和盆底肌锻炼对产妇盆底功能的影响。方法选择2019年1月至2023年1月我院收治的104例产妇,根据干预方式不同分为对照组(n=50)和研究组(n=54)。对照组给予常规妊娠指导和护理,研究组则在妊娠28周后加用盆底肌锻炼。比较两组产后8周的盆底功能和盆底超声检查结果。结果研究组盆底肌力等级显著优于对照组,压力性尿失禁发生率显著低于对照组(P<0.05)。研究组CD、LHD-d、LHLR-d、RAD、BND显著低于对照组(P<0.05)。结论盆底超声可评估妊娠、分娩和盆底肌锻炼产妇的盆底功能;盆底肌锻炼能够显著改善产妇的盆底功能,减少盆腔结构变化,降低压力性尿失禁发生率。 展开更多
关键词 盆底超声 盆底肌锻炼 产妇 盆底功能
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地震作用下掉层钢框架结构抗倒塌能力分析
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作者 刘杰 伍云天 +1 位作者 姜学忠 李永昌 《建筑结构》 北大核心 2024年第3期118-125,共8页
采用PERFORM-3D程序对掉层钢框架结构进行了抗震倒塌能力研究。考虑不同的掉层情况和结构措施,设计了2个普通钢框架结构模型和4个掉层钢框架结构模型(其中2个模型带拉梁加强),利用增量动力分析方法对上述钢框架模型进行了易损性分析和... 采用PERFORM-3D程序对掉层钢框架结构进行了抗震倒塌能力研究。考虑不同的掉层情况和结构措施,设计了2个普通钢框架结构模型和4个掉层钢框架结构模型(其中2个模型带拉梁加强),利用增量动力分析方法对上述钢框架模型进行了易损性分析和抗震倒塌能力评估。结果表明,掉层钢框架结构的抗震倒塌能力与掉层数关系不大;采用拉梁加强的掉层钢框架,上接地侧的抗震倒塌能力和抗震倒塌安全储备性能有所提高,但掉层侧的抗震倒塌能力和抗地震倒塌安全储备降低;增加拉梁的数量对该类结构影响不大,但会改变其破坏模式;上接地侧倒塌模式下,上接地一层是上接地侧最薄弱的楼层;掉层侧倒塌模式下,上接地二层是掉层侧最薄弱的楼层。 展开更多
关键词 掉层钢框架结构 拉梁 抗震倒塌能力 易损性分析 增量动力分析
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腹腔镜子宫肌瘤剔除术对子宫肌瘤患者盆底功能、卵巢功能的影响
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作者 张琳 张颖 徐流立 《临床研究》 2024年第1期80-83,共4页
目的探讨腹腔镜子宫肌瘤剔除术(LM)对子宫肌瘤患者盆底功能、卵巢功能的影响。方法纳入2021年1月至2022年10月濮阳市安阳地区医院收治的80例子宫肌瘤患者,按抽签法分两组。对照组40例行开腹子宫肌瘤剔除术(AM),研究组40例行LM,对比两组... 目的探讨腹腔镜子宫肌瘤剔除术(LM)对子宫肌瘤患者盆底功能、卵巢功能的影响。方法纳入2021年1月至2022年10月濮阳市安阳地区医院收治的80例子宫肌瘤患者,按抽签法分两组。对照组40例行开腹子宫肌瘤剔除术(AM),研究组40例行LM,对比两组手术前后疼痛因子[心肌细胞P物质(SP)、前列腺素E_2(PGE_2)]、应激反应指标[去甲肾上腺素(NE)、皮质醇(COR)]、免疫功能指标(CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+))、盆底功能指标[盆底障碍影响简易问卷7(PFIQ-7)]及卵巢功能指标[雌二醇(E_2)、促黄体生成素(LH)、促卵泡激素(FSH)]。结果术后1 d、术后3 d时,研究组血清SP、PGE_2、NE、COR水平低于对照组,差异有统计学意义(P<0.05)。术后1d时,两组CD3^(+)、CD4^(+)及CD4^(+)/CD8^(+)功能指标与术前相比均有所降低,但研究组明显高于对照组,差异有统计学意义(P<0.05);而两组的CD8^(+)功能指标与术前相比有所升高,但研究组明显低于对照组,差异有统计学意义(P<0.05)。术后1个月、术后3个月时,两组PFIQ-7评分均有所升高,但研究组明显低于对照组,差异有统计学意义(P<0.05)。术后3个月、术后6个月时,研究组血清E_2水平高于对照组,而血清LH、FSH水平低于对照组,差异有统计学意义(P<0.05)。结论对子宫肌瘤患者行LM可有效减轻机体疼痛程度、应激反应及对免疫、盆底和卵巢功能的负面影响,优势较为显著,具有进一步的使用价值。 展开更多
关键词 子宫肌瘤 腹腔镜子宫肌瘤剔除术 盆底功能 卵巢功能
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典型水深与海底介质条件下的OBC/OBN多分量地震数据波型特征
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作者 王腾飞 刘学义 程玖兵 《石油物探》 CSCD 北大核心 2024年第1期45-60,共16页
海底电缆或海底节点(OBC/OBN)多分量地震是开展海上复杂油气藏勘探的重要手段之一。由于地震波与自由表面及海底界面的互相作用,海底多分量地震记录中波型成分十分复杂。调查其中各类信号与噪声的形成机制及其影响,可为后续数据处理与... 海底电缆或海底节点(OBC/OBN)多分量地震是开展海上复杂油气藏勘探的重要手段之一。由于地震波与自由表面及海底界面的互相作用,海底多分量地震记录中波型成分十分复杂。调查其中各类信号与噪声的形成机制及其影响,可为后续数据处理与解释提供关键依据。针对海底多分量地震观测条件下潜在的波场信号,按照不同水深与典型海底沉积物性质构建代表性的弹性参数模型,利用谱元法合成OBC/OBN多分量地震记录,分析各类波型成分的表现特征,揭示水深和海底介质特性对波场运动学及动力学特征的影响。通过与东海浅水区和南海深水区海底地震仪(OBS)采集的实际地震数据的对比分析,确认了水深与海底介质条件对表面多次波与海底界面波的调控机理,为海底多分量地震数据处理方法研究与技术应用提供有益的指导。 展开更多
关键词 海底多分量地震 海底界面效应 P-S模式耦合 自由表面多次波 海底地震仪 OBC/OBN
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