Indispensable gutter layers in thin-film composite membranes for carbon capture

Industrial thin-film composite(TFC)membranes achieve superior gas separation properties from high-performance selective layer materials,while the success of membrane technology relies on high-performance gutter layers to achieve production scalability and low-cost manufacturing.However,the current literature predominantly focuses on the design of polymer architectures to obtain high permeability and selectivity,while the art of fabricating gutter layers is usually safeguarded by industrial manufacturers and appears lackluster to academic researchers.This is the first report aiming to provide a comprehensive and critical review of state-of-the-art gutter layer materials and their design and modification to enable TFC membranes with superior separation performance.We first elucidate the importance of the gutter layer on membrane performance through modeling and experimental results.Then various gutter layer materials used to obtain high-performance composite membranes are critically reviewed,and the strategies to improve their compatibility with the selective layer are highlighted,such as oxygen plasma treatment,polydopamine deposition,and surface grafting.Finally,we present the opportunities of the gutter layer design for practical applications.

Characterization and Application of the Makoua Clay in the Chemical and Bacteriological Depollution of Gutter and Well Waters of Brazzaville

In this work, the authors made aquatic filters according to the formulation “clay stabilized at 4% of cement mixed with 4% of kambala sawdust and 10% of white sand” then heated to 1050°C to decontaminate the waters of gutters and wells. The authors carried out geotechnical, geochemical, thermal, infrared spectroscopy, and scanning electron microscopy that analyzed the clay material. Geotechnical analyzes have shown that this material is made up of 22% thin sand, 22% of silt, and 56% of clay with 26 plasticity index. The geochemical analysis showed the presence of trace elements shared out as follows: 3% of alkaline metals, 24% of alkaline earth metals, 46% of transition metals, 10% of metal, 16% of lanthanides, 1% of actinides. The most abundant trace elements are barium (19%), vanadium (12%), chromium (11%) and zinc (9%). The thermal and microscopic analyzes revealed the kaolinitic nature of materials. The chemical depollution studies have shown elimination yields of 50% - 52.38% of sulphates;77.33% - 85.19% of phosphates;34.85% - 88.49% nitrates;91.3 - 100 of sulphides;The removal of bacteriological pollution are 92.8% - 98% of total germs;94% - 97% of total coliform and 95% - 98% of E. coli.

Total Peritoneal Gutter Removal versus Random Peritoneal Biopsy in Cases of Ovarian Cancer

Introduction: Ovarian cancer is the fourth most prevalent cancer among women and the seventh most common cancer overall. Every year, an estimated 200,000 cases and 125,000 deaths related to ovarian cancer are reported around the world. It is most common in high-resource countries, with an incidence rate of 9.3 per 100,000 women. Ovarian cancer is detected at an advanced stage in about 70% of instances, and only 30% of women with such cancers live for more than 5 years. Although only around 20% of ovarian cancers are limited to the ovaries at diagnosis, patients with localized disease have a 5-year survival rate of more than 90%. Peritonectomy is a crucial part of the surgical treatment for ovarian cancer. Visual inspection and palpation are not reliable methods for determining the extent of tumour involvement. The majority of gynecologic oncologists are suspicious about the benefits of a full peritonectomy, concerned about the benefits and hazards. They believe that the tumor’s fundamental biology, not surgical aggressiveness, dictates the tumor’s resectability. The aim of this work was primarily to compare the differences between total peritoneal gutter removal and random peritoneal biopsy in cases of early ovarian cancer. A secondary aim of this work is to show ability of total peritoneal gutter removal in relation to that of random peritoneal biopsy to detect positivity of metastasis in the histopathological specimens. Patients and Methods: This prospective cohort study was conducted on 130 patients with early ovarian cancer in El-Shatby hospital, Faculty of Medicine, Alexandria University. For each patient, we took random and total peritoneal biopsy and compared between them regarding technique, timing, post-operative complications, and histopathological results. Inclusion criteria: all age group, suspected ovarian cancer using IOTA score, absence of nodules in the peritoneal gutter using CT and any case that needs staging laparotomy for ovarian cancer. Exclusion criteria: presence of gross peritoneal disease in the gutter and CT features of advanced ovarian cancer (peritoneal deposits, omental cakes, pelvic and para-aortic lymphadenopathy). All cases will be subjected to the followings: history taking, clinical examination, suspicious ovarian mass using IOTA score, tumor markers, CT staging, staging laparotomy and random and total peritoneal biopsies will be collected from the same case and sent to the lab of pathology for histopathological examination and the results will be compred regarding positivity of metastasis. Results: Random peritoneal biopsy showed positive metastasis in 6 (4.6%) cases and free in 124 (95.4%) cases while total peritoneal gutter removal showed positive metastasis in 19 (14.6%) cases and free in 111 (85.4%) with Chi-square test was 7.479 and P value was 0.004 which is statistically significant. 108 (97.3%) cases had negative random peritoneal biopsy and negative total peritoneal gutter removal, 3 (2.7%) cases had positive random peritoneal biopsy and negative total peritoneal gutter removal, 16 (84.2%) cases had positive total peritoneal gutter removal and negative random peritoneal biopsy & 3 (15.8%) cases had positive total peritoneal gutter removal and positive random peritoneal biopsy with Chi-square test 6.311, FEp 0.04 and Kappa test 0.183 (0.012) which is statistically significant with poor strength of agreement. Conclusions: Modified total peritoneal gutter removal is a safe, fast and easy technique compared to random peritoneal biopsy and even to traditional peritonectomy procedure with high detection rates of peritoneal involvement with sensitivity of 50% and specificity of 87.5% and it is recommended to be done as a routine alternative to random peritoneal biopsy and even to traditional total gutter removal in all cases of ovarian malignancies for diagnostic and therapeutic values.

基于不同数字地形模型的城市内涝模拟

城市内涝是威胁人民生命财产安全的主要自然灾害之一。地势低洼、建筑密度大、地面渗水能力弱的城中村或社区,更容易引发城市内涝。情景模拟是城市内涝防治的有效手段,但对于城市内涝模拟采用何种地形数据长期存在争议。以广州市中心城区两处易涝区为研究对象,采用广州市暴雨强度公式模拟该区域3种雨型的强降水过程;根据雨水口综合流速公式分析排水能力,分别结合数字表面模型和数字高程模型模拟地表汇水情况,并通过淹没深度对该区域内涝风险进行评估。结果表明,数字表面模型能比数字高程模型更好地模拟高密度建筑区的内涝情况,模拟结果对推进该区域排水系统建设和更全面开展城市雨洪模拟具有一定的参考价值。

高强螺栓锥孔灌浆连接的预制天沟抗剪性能试验研究

针对装配式混凝土建筑工程中多采用现浇天沟导致安装工序复杂的问题,为了探讨预制天沟替代现浇天沟的可行性,提出一种由预留锥形灌浆孔、高强螺栓、螺母、紧固件和高强灌浆料构成的预制构件连接方式,即“高强螺栓锥孔灌浆连接方式”,并对采用该种连接的简化天沟试件进行竖向力加载试验,研究预制天沟与预制混凝土剪力墙结合面的抗剪性能。结果表明:高强螺栓锥孔灌浆连接的预制天沟性能可靠,剪力作用下,试件未发生脆性破坏,螺栓未断裂;天沟等非结构预制构件,可以采用该种连接方式与预制结构构件连接;提出了该种构造下单个螺栓连接件的抗剪承载力计算公式,可为工程应用提供参考。

南方某高铁主站房屋面虹吸雨水排水系统研究

南方某高铁站作为华南地区核心交通枢纽,承担繁重的客运任务。站房作为高铁站的主体建筑,该建筑面积较大,屋顶设计坡度较小,雨水排放存在一定压力。更为严重的是,在遇到雨水天气时,由于倾斜角度不够大,雨水可能会倒灌而进入室内,引发安全隐患。为解决这一问题,该站房采用了2套独立的虹吸雨水排水系统。本文以主站房屋面虹吸系统设计为基础,深入分析天沟挡水板的设计参数和汇水系统的整体结构;通过在屋面结构最低点处,计算校核管道系统的水力,系统地分析不同节点压力值、水头损失对虹吸系统运行维护的影响。同时,针对排水系统中可能存在的问题,提出可行性建议。以期为其他高铁站的屋面排水系统设计提供理论支撑,推动虹吸雨水排水系统的深入研究,以应对不同环境条件下的雨水排放问题。

地沟油脂肪酸捕收剂对异极矿的浮选机制研究

为了探究天然脂肪酸类捕收剂直接浮选异极矿替代传统硫胺法浮选的可行性,采用尿素包合法分离提纯地沟油中的天然脂肪酸用作异极矿浮选捕收剂,借助异极矿浮选试验确定适宜的分离参数及地沟油脂肪酸捕收剂浮选异极矿的行为规律。通过Zeta电位、FT-IR和XPS等分析检测手段揭示地沟油脂肪酸捕收剂在异极矿表面的作用机理。结果表明,当尿素和混合脂肪酸的质量比为1∶1时,经尿素包合法分离制备的地沟油不饱和脂肪酸捕收剂(DG-N)具有优异的浮选性能。在捕收剂DG-N质量浓度为200 mg/L、矿浆pH值为6~10、搅拌转速为200 r/min、充气量为80 mL/min的条件下,单泡浮选管浮选异极矿的回收率超过95%。Zeta电位和FT-IR分析结果表明,异极矿与捕收剂DG-N作用后表面Zeta电位值显著降低,作用后的FT-IR谱图中出现了明显的捕收剂DG-N特征峰,且异极矿表面Si-O和Zn-O键的红外波数发生了明显偏移,表明捕收剂DG-N在异极矿表面发生了吸附。XPS分析结果表明,吸附前后Zn 2p、O 1s、C 1s和Si 2p元素含量和化学态发生了变化,说明了捕收剂DG-N在异极矿的表面吸附过程涉及化学作用。机理研究表明地沟油捕收剂DG-N与异极矿表面存在强烈的化学作用,克服了静电斥力吸附在异极矿表面,从而使异极矿疏水上浮。研究结果可为地沟油制备浮选捕收剂和脂肪酸直接浮选异极矿提供有益的理论依据。

汽车天窗漏水原因分析与方案优化

为解决汽车天窗漏水问题,以底装式天窗结构为基础,研究了车身与车顶密封条之间漏水、车顶密封条与天窗玻璃之间漏水、水流翻过导水槽漏水3种天窗漏水模式,发现漏水原因与天窗密封条、天窗导水槽、天窗排水管、车身、装配等因素有关,结果表明,改善车顶密封条的形式、压缩载荷性能、与环境件之间的配合以及接头质量,改进导水槽的布置、结构与导水量,改进排水管的形式、布置、排水量,改善车身的翻边尺寸与表面质量,优化装配环境、手法与工装定位,可有效解决天窗漏水问题。

大型国际航站楼异形双曲金属屋面系统施工研究

以杭州萧山国际机场三期项目新建T4航站楼为例,研究了超大面积异形双曲钢结构金属屋面系统、不锈钢天沟系统、天窗系统、不锈钢防坠落系统和防雷系统施工工艺及施工关键技术,提炼总结形成超大面积异形双曲金属屋面施工成套技术,实现了各系统的精准安装,为后续大型会议会展场馆和机场类超大型建筑金属屋面施工提供可借鉴经验。

不同侧沟深度和刺激剂对思茅松产脂量和树脂道的影响

采用“V”字形下降式采脂法,割脂频率为1 d 1次。设置不同侧沟深度(伤及木质部2~3 mm和仅伤及韧皮部)和不同刺激剂(刺激剂D和刺激剂J)的组合处理。结果表明:不同侧沟深度对产脂量和树脂道数量均无显著影响;同一侧沟深度处理下,刺激剂D和刺激剂J处理能显著增加产脂量,尤其是刺激剂J对仅伤及韧皮部的处理增脂效果最佳,增脂率达27%;添加刺激剂均能显著促进新生树脂道数量的增加,增长率在257%~398%;添加刺激剂处理能促进树脂道数量增加,但单个树脂道面积会减小。

工业厂房屋面自承重式冷弯成型天沟的研究与应用

天沟是工业厂房屋面排水系统中重要的组成部分,具有承上启下的作用。当前工程应用中的构造较为烦琐,对制造和安装的要求较高,耐久性也难以保证。分析天沟的各种不同承载工况与相应的受力模型,针对性优化其构造措施,将为天沟标准化生产创造有利条件。经研究和实践应用对比分析,优化后的自承重式一体成型冷弯薄壁型钢天沟更加节能环保,施工制造、施工安装便捷,工程适应性强,具有显著的经济效益,应用前景良好。

浅析超低温球阀的典型结构设计要点

当前在LNG液化天然气接收站现场,所使用的低温球阀存在填料容易因冷凝水流入而结冰、加长阀杆憋死导致扭矩异常变大、SPE和DPE活塞密封圈易扭曲变形损坏等常见故障。针对以上三个典型的高发问题点,本文结合一些国内外典型的设计经验,采用加长套顶部排水槽的设计方案,利用高度差顺利将冷凝水排出,有效防止其流入填料函而形成结冰;采用Lip-seal+填料垫一体式轴套+低泄漏填料组合方案,解决阀杆不同心而导致扭矩变大的问题;采用封闭槽的设计,解决SPE端Lip-seal易扭曲损坏的问题。本文分别对以上三个设计方案做简单的剖析介绍,从细节上优化解决难点。

乌鲁木齐机场T4航站楼双曲面金属屋面工程设计

乌鲁木齐机场T4航站楼为双曲造型的金属屋面,在实现建筑美学追求的同时,也给工程在设计与安装施工上带来诸多挑战。本文重点介绍了该项目的金属屋面系统、天沟系统、采光天窗系统、檐口蜂窝铝板系统和室外吊顶系统的设计要点、安装施工难点及采用的创新性解决方案。

溃堤洪水在有压雨水管网街区演进的试验研究

溃堤洪水在有压雨水管网街区的演进过程十分复杂,城市街区建筑物及雨水管网改变了洪水的演进规律,影响了街区排涝的水力特性。本文基于典型城市街区建立了包括房屋、人行道及雨水管网在内的概化水槽模型,测量了不同溃堤洪水在典型城市街区演进过程中的街区水深、雨水管网流量及压强,探究了不同蓄水高度、前池进口流量对街区水位波动变化及有压雨水管网下泄流量的影响。溃堤洪水在水槽侧壁、房屋的作用下形成了大面积的水跃,并且在房屋建筑物附近出现了薄层状水片,水跃区域伴随着洪水演进过程先是在人行道处发生横向的迁移合并,再是在街区道路的纵向方向上逐渐耗散直至消失,街区水位在100 s后基本稳定,从上游至下游呈“先增大、再减小”的变化趋势。溃堤洪水在街区演进过程中,不同蓄水高度对有压雨水管网的泄流量影响相较于不同前池进口流量更加显著,街区上游雨水口的峰值流量在最大蓄水高度条件约为最大前池进口流量的1.5倍。研究结合街区水位及有压雨水管网压强采用欧拉数对短管淹没出流公式的泄流系数进行了率定,修正后的理论计算值的误差由32%降低至2%,能够较好地反映出街区雨水口的泄流能力。研究成果不仅能为数学模型提供翔实的验证资料,还可为城市洪涝治理提供理论指导。

设施蔬菜产业发展(六) 我国规模化连栋玻璃温室发展现状与建议

规模化连栋玻璃温室单体规模大、环境调控能力强,普遍采用无土栽培技术,能突破资源环境制约,极大拓展了农业生产的可能性边界,是现代设施种植业的典型代表,近年来在我国得到迅猛发展。文章基于现状调研,结合文献分析,总结了规模化连栋玻璃温室近年来呈现出的区域布局向中西部拓展、结构标准化、装备国产化、管理数字化等发展特征,分析了发展过程中存在的科学谋划和顶层设计缺位,部分关键核心技术装备主要依赖进口,单位产出率偏低、运行成本过高影响温室生产效益和可持续发展等问题,提出了科学合理选址、因地制宜建设、适度从严审批,加大关键技术研发、降低投资和运营成本,加强人才培养、注重品牌建设、提高可持续发展能力等未来发展建议。

基于明沟集水井的肥槽降排水改进措施

随着建筑地下结构开挖深度越来越大,肥槽积水导致的问题愈发明显。为了将肥槽积水有效外排,首先介绍基于明沟集水井进行肥槽降排水的原理,然后指出该方法在当前应用中存在的缺陷,即难以将坑底的积水排尽。剩余积水将引发防水施工困难、外墙脚手架底部锈蚀和坑底垃圾清理困难的问题。最后,提出了两点改进措施:一是将肥槽底板做成斜坡,以保证剩余积水流入明沟;二是制作混凝土三棱柱预制块,以保证斜坡上的脚手架的稳定性。结果表明,改进措施不仅可以很好地解决肥槽坑底积水排不尽的问题,而且具有不增加施工成本的优点。

耀雪冰雪世界滑雪场金属屋面施工工艺研究

依托耀雪冰雪世界滑雪场项目的金属屋面施工实践,主要以屋面围护系统的构造做法及类型为基础,重点介绍屋面天沟系统、上表面铝镁锰合金直立锁边屋面板系统、屋面集成保温体系的构造形式以及施工工艺,可为对屋面保温体系性能有较高要求的类似项目提供借鉴。

严寒地区车库采用散热器地沟敷设供暖研究

在严寒、寒冷地区地面具有高大空间特点的停车库供暖问题上,提出了一种不受外墙敷设空间影响的地沟散热器安装供暖方案,并利用Airpak气流组织模拟手段,对供暖方案的供暖效果进行计算。通过计算结果可知,采用散热器地沟安装供暖方案,散热器表面能够产生稳定的上升气流,空气流动最大风速达到0.47m/s,车库内部整体温度能够达到采暖设计温度;考虑外窗、外门及外墙内壁温度较低,对于车库内部安装的宜结冻管道、设备应适当保持一定距离。

地沟油冷再生沥青混合料路用性能研究

将地沟油作为老化沥青再生剂,通过再生沥青三大指标及再生沥青混合料劈裂强度、浸水马歇尔稳定度和四点弯曲疲劳寿命等测试,研究了地沟油对老化沥青再生性能及冷再生混合料路用性能的影响。结果表明:地沟油掺量在15%时再生沥青的性能基本达到70^(#)基质沥青要求;铣刨料掺量相同时,随地沟油掺量增加,冷再生混合料力学性能、低温性能、水稳定性逐渐提高,高温稳定性能降低,疲劳寿命呈先延长后缩短的趋势;地沟油掺量相同时,随铣刨料掺量增加,混合料的力学性能、低温性能、水稳定性降低,高温稳定性能提高,疲劳寿命缩短。

地沟油制备水溶性咪唑啉缓蚀剂及其缓蚀性能研究

以地沟油、二乙烯三胺为原料制备咪唑啉缓蚀剂,当地沟油与二乙烯三胺摩尔比为1:1.2,环化温度为140℃,时间为3 h,酰胺化温度为150~160℃,时间为2 h,季铵化温度为140℃,反应时间为3~4 h,可合成水溶性咪唑啉缓蚀剂。通过静态挂片失重法和电化学极化法对其缓蚀效果进行评价,结果表明,在1mol/L的盐酸介质中,当缓蚀剂添加量浓度为100 mg/L时,缓蚀性能最好。存放1 d的缓蚀剂缓蚀效率可高达99.02%。存放6个月后的缓蚀剂缓蚀效率下降为95.76%,仍能很好地满足工业要求。电化学极化曲线可以看出此法制备的咪唑啉缓蚀剂为阴极型缓蚀剂。