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气源及活性剂对曝气滴灌带水气单双向传输均匀性的影响

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农业工程学报 2018年第19期34卷 88-94页

作者：雷宏军刘欢 Bhattarai Surya Balsys ron 潘红卫华北水利水电大学水利学院郑州450046 澳大利亚中央昆士兰大学医学与应用科学学院罗克汉普顿4702 澳大利亚中央昆士兰大学工程与技术学院罗克汉普顿4702

曝气滴灌过程中水、氧、气传输均匀性是评价曝气灌溉质量的重要指标。活性剂的添加和传输方式的优选对曝气滴灌传输过程中微气泡的存在和溶解氧的保持有重要意义。为提高水气耦合物在滴灌过程中传输的距离和均匀性,该文采用Mazzei 1078... 详细信息

曝气滴灌过程中水、氧、气传输均匀性是评价曝气灌溉质量的重要指标。活性剂的添加和传输方式的优选对曝气滴灌传输过程中微气泡的存在和溶解氧的保持有重要意义。为提高水气耦合物在滴灌过程中传输的距离和均匀性,该文采用Mazzei 1078文丘里空气射流器进行曝气增氧,以空气和氧气为供试气源,研究活性剂BS1000浓度(0、1、2和4 mg/L)和传输方式(单向和双向)对曝气滴灌下水、氧、气传输特性的影响。结果表明:曝气导致单向传输下流量均匀性略有下降,但可显著提高灌溉水中溶解氧和掺气比例;随着活性剂浓度的增加,掺气比例显著增加(P<0.05);活性剂的添加促进了氧气曝气下溶解氧的增加;溶氧均匀性和流量均匀性随着活性剂浓度的增加无显著性变化,但单向传输下4 mg/L BS1000的出气均匀性较未添加活性剂显著降低;双向传输的流量均匀性、溶氧均匀性和出气均匀性分别在95%、96%和67%以上,较单向传输分别平均提高14.00%、4.05%和30.64%(P<0.05),是曝气滴灌长程管道传输推荐的布置方式。研究结果为曝气滴灌过程中灌溉技术参数优化和管道的科学布置提供理论依据。

关键词：溶解氧传输灌溉曝气滴灌微气泡掺气比例均匀性

NaCl及生物降解活性剂对曝气灌溉水氧传输特性的影响

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农业工程学报 2017年第5期33卷 96-101页

作者：雷宏军刘欢张振华 Bhattarai Surya Balsys ron 华北水利水电大学水利学院郑州450045 鲁东大学地理与规划学院烟台264025 澳大利亚中央昆士兰大学医学与应用科学学院澳大利亚中央昆士兰大学工程与技术学院

曝气灌溉可有效调节植物根区环境、改善土壤通气性。微咸水中NaCl的存在及活性剂添加对提高曝气灌溉的氧传质效率,实现节能高效的灌溉有重要作用。为研究NaCl介质及生物降解活性剂对纯氧曝气灌溉水氧传输特性的影响,该文采用变压分离制... 详细信息

曝气灌溉可有效调节植物根区环境、改善土壤通气性。微咸水中NaCl的存在及活性剂添加对提高曝气灌溉的氧传质效率,实现节能高效的灌溉有重要作用。为研究NaCl介质及生物降解活性剂对纯氧曝气灌溉水氧传输特性的影响,该文采用变压分离制氧技术-氧气扩散系统-空气注射技术耦合系统,分析NaCl介质(未添加和添加)及生物降解活性剂BS1000(醇烷氧基化物质量浓度0、1、2、4 mg/L)2个因素对氧总传质系数、溶氧饱和度、流量均匀系数和溶氧均匀系数的影响。结果表明:BS1000的添加促进氧传质过程的发生,提高了曝气水中的溶氧饱和度;随着BS1000浓度增加,氧总传质系数逐渐增加,而溶氧饱和度呈现下降的趋势;BS1000质量浓度在2 mg/L及以上时,NaCl介质对氧总传质系数的增幅显著;NaCl介质对曝气水中的溶氧饱和度起到抑制作用。各组合条件下,曝气滴灌中流量均匀系数均在95%以上,溶氧均匀系数均在97%以上。添加活性剂BS1000可使氧总传质系数平均提高18.85%以上(P<0.05)。无论添加NaCl与否,添加1 mg/L BS1000的溶氧饱和度均最大,故1 mg/L BS1000是适宜的活性剂添加浓度。

关键词：咸水溶解氧灌溉纯氧曝气 BS1000 氧总传质系数饱和度均匀性

Attention deficit hyperactivity disorder and gastrointestinal morbidity in a large cohort of young adults

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World Journal of Gastroenterology 2020年第42期26卷 6626-6637页

作者： Sivan Kedem Shlomit Yust-Katz Dan Carter Zohar Levi ron Kedem Adi Dickstein Salah Daher Lior H Katz Medical Corps Israeli Defense ForcesRamat-Gan 52621Israel Medical School Hebrew University-Hadassah Medical CenterJerusalem 91120Israel Sackler Faculty of Medicine Tel-Aviv UniversityTel-Aviv 77096Israel Neuro-Oncology Unit Davidoff Cancer CenterRabin Medical CenterPetach Tikva 49100Israel Department of Gastroenterology Sheba Medical CenterRamat-Gan 52361Israel Department of Gastroenterology Beilinson HospitalRabin Medical CenterPetach Tikva 49100Israel Department of Gastroenterology and Hepatology Hebrew University-Hadassah Medical CenterJerusalem 91120Israel

BACKGROUND Although the association of attention deficit hyperactivity disorder(ADHD)with psychiatric disorders is well known,its association with somatic diseases is *** few studies have investigated the gastrointestinal(GI)morbidity in adult patients with *** To measure gastrointestinal comorbidity and its burden on healthcare in young adults with *** The cohort included subjects aged 17-35 years recruited to the Israel Defense Forces in 2007-2013,33380 with ADHD and 355652 without(controls).The groups were compared for functional and inflammatory conditions of the gastrointestinal tract and clinic and specialist visits for gastrointestinal symptoms/disease during service(to 2016).Findings were analyzed by generalized linear models adjusted for background *** Compared to controls,the ADHD group had more diagnoses of functional gastrointestinal disorders(referred to as FGID),namely,dyspepsia[odds ratio(OR):1.48,95%confidence interval(CI):1.40-1.57,Pronic constipation(OR:1.64,95%CI:1.48-1.81,P<0.001),and irritable bowel syndrome(OR:1.67,95%CI:1.56-1.80,P<0.001)but not of organic disorders(inflammatory bowel disease,celiac disease).They had more frequent primary care visits for gastrointestinal symptoms[rate ratio(RR):1.25,95%CI:1.24-1.26,P<0.001]and referrals to gastrointestinal specialists(RR:1.96,95%CI:1.88-2.03,P<0.001)and more episodes of recurrent gastrointestinal symptoms(RR:1.29,95%CI:1.21-1.38,P<0.001).Methylphenidate use increased the risk of dyspepsia(OR:1.49,95%CI:1.28-1.73,P<0.001)and constipation(OR:1.42,95%CI:1.09-1.84,P=0.009).CONCLUSION ADHD in young adults is associated with an excess of FGID and increased use of related health *** is needed to determine if an integrative approach treating both conditions will benefit these patients and cut costs.

关键词： Functional gastrointestinal disorders Irritable bowel syndrome Dyspepsia Constipation Adolescents

Moose at their bioclimatic edge alter their behavior based on weather, landscape, and predators

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Current Zoology 2018年第4期64卷 419-432页

作者： Mark A. DITMER ron A. MOEN Steve K. WINDELS James D. FORESTER Thomas E, NESS Tara R. HARRIS Conservation Department Minnesota Zoo 13000 Zoo Boulevard Apple Valley MN 55124 USA Department of Fisheries Wildlife and Conservation Biology University of Minnesota 2003 Upper Buford Circle Ste 135 St Paul MN 55108 USA Natural Resources Research Institute and Department of Biology University of Minnesota Duluth 5013 Miller Trunk Highway Duluth MN 55811 USA Voyageurs National Park 360 Hwy 11 E International Falls MN 56649 USA

Populations inhabiting the bioclimatic edges of a species＇ geographic range face an increasing amount of stress from alterations to their environment associated with climate change. Moose Alces alces are large-bodied ungulates that are sensitive to heat stress and have exhibited population declines and range contractions along their southern geographic extent. Using a hidden Markov model to analyze movement and accelerometer data, we assigned behaviors （rest, forage, or travel） to all locations of global positioning system-collared moose （n = 13, moose-years = 19） living near the southern edge of the species＇ range in and around Voyageurs National Park, MN, USA. We assessed how moose behavior changed relative to weather, landscape, and the presence of predators. Moose sig- nificantly reduced travel and increased resting behaviors at ambient temperatures as low as 15~C and 24~C during the spring and summer, respectively. In general, moose behavior changed season- ally in association with distance to lakes and ponds. Moose used wetlands for travel throughout the year, rested in conifer forests, and foraged in shrublands. The influence of wolves Canis lupus varied among individual moose and season, but the largest influence was a reduction in travel during spring when near a wolf home range core, primarily by pregnant females. Our analysis goes beyond habitat selection to capture how moose alter their activities based on their environment. Our findings, along with climate change forecasts, suggest that moose in this area will be required to further alter their activity patterns and space use in order to find sufficient forage and avoid heat stress.

关键词： Alces alces climate change heat stress moose temperature wolves

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Shaping the Future

ChinAfrica 2013年第7期5卷 34-35页

作者： Hannah Edinger ron Sandrey Research&Strategy at Frontier Advisory the Trade Law Center of Southern Africa

SINCE the turn of the century, China has become Africa＇s largest trading partner. While Sino- African relations are often touted as ＂win-win＂ by Chinese and African leaders, trade relations have been criticized for being unbalanced as Africa＇s natural resources are traded for Chinese-manufactured consumer goods. This relatively unequal trade structure has led many to suggest that China＇s manufactured exports are cutting into opportunities for African industrialization.

关键词： US Shaping the Future

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压缩级别知难而上!

中外管理 2005年第10期 45-46页

作者： ron Nicol 波士顿咨询公司

让组织变得更灵活起来，是很多CEO的大难题，问题究竟出在哪儿？往往人们回避做的事，不是认为这事不该做，而是不知道如何把事做正确。

关键词：组织机构决策机制人力资源管理级别压缩企业管理

Investigation on relations between grain crushing amount and void ratio change of granular materials in one-dimensional compression and creep tests

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Journal of Rock Mechanics and Geotechnical Engineering 2011年第S1期3卷 415-420页

作者： ron.C.K.Wong Department of Civil Engineering University of Calgary

Grain crushing plays an important role in one-dimensional (1D) compression and creep behaviors of granular materials under high stress. It is clear that the macro-properties of granular materials are closely related to the micro-fracture properties of grains in 1D compression and creep tests. In this paper, a series of 1D compression and creep tests were performed on Ottawa sand to investigate the deformation and grain crushing properties of granular materials, and it shows that the void ratio is correlated to the grain crushing amount (the quantity of crushed grains) for granular materials subjected to grain crushing. The test results, combining with the existing test data related to grain crushing of granular materials, were used to verify the relation. Moreover, the implications of these relations on the yield of granular material, and the equivalent effect of stress and time in changing soil fabric are presented.

关键词： granular material grain crushing geometrical aspect one-dimensional (1D) compression and creep yield soil fabric

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DESIGN

明日风尚 2010年第4期 72-73页

作者： ron Lam Carrie Tsang

01向传统致敬以都柏林为根据地,由爱尔兰设计师Gearoid Muldowney于2008年创立的独立设计工作室Superfolk,旗下每一项设计都是向当地传统的民间创作工艺致敬。利用爱尔兰本土盛产的天然物料:羊毛、木材及皮革,糅合坊间的手工艺技术,并... 详细信息

01向传统致敬以都柏林为根据地,由爱尔兰设计师Gearoid Muldowney于2008年创立的独立设计工作室Superfolk,旗下每一项设计都是向当地传统的民间创作工艺致敬。利用爱尔兰本土盛产的天然物料:羊毛、木材及皮革,糅合坊间的手工艺技术,并从寻常生活中取材。Supetfolk最近就推出一系列洋溢爱尔兰民族特色的家具,包括由胡桃木制成的长餐桌,可自由组合的凳子,全人手制作的墙纸,及以制作柳木家品和篮子而闻名都柏林的工匠Joe Hogan交叉合作的藤制灯罩,重新演绎出实用、创意又富传统生活智慧的家具设计。***.

关键词：家具设计爱尔兰民族设计工作室民间创作生活智慧 DESIGN 胡桃木柳木陶瓷作品陶瓷餐具

Hotel Tech Trends to Watch

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中国会展 2018年第8期 67-69页

作者： ron Donoho Fu Xiao 不详

Whether its chatbot concierges or self-check-in kiosks,hotels are getting *** recognition *** and augmented ***'s a seemingly unending stream of cool tech tools flowing out of research-and-development centers and into all corners of the meeting and haspiality ***'s influencing hotel and event check-in processes,adding bells and whistles to guest rooms,and innovating meeting *** borrow from Thomas Dolby,they're blinding us with *** delving into the latest tech trends,it's worthwhile to hear the consensus view from meeting planners,hoteliers,and futurists who focus on the hospitality industry:Technology will enhance but never replace the way hotels cater toguests.

关键词： self-check-in kiosks Thomas Dolby meeting planners