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mAP沉淀法目标产物最优形成条件及分析方法

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环境科学 2009年第4期30卷 1120-1125页

作者：郝晓地兰荔王崇臣 van loosdrecht m C m 北京建筑工程学院可持续环境生物技术研发中心北京100044 荷兰代尔夫特理工大学Kluyver生物技术实验室荷兰Delft 2628 BC

为了确定鸟粪石（mAP：mgNH4PO4.6H2O）形成的最优条件,引入化学剖析法,利用酸溶液将鸟粪石沉淀法中所得沉淀物溶解后进行相应的元素分析;提出一种根据沉淀物中的NH4^＋-N含量间接计算确定鸟粪石含量（即纯度）的分析方法.根据这种计算... 详细信息

为了确定鸟粪石（mAP：mgNH4PO4.6H2O）形成的最优条件,引入化学剖析法,利用酸溶液将鸟粪石沉淀法中所得沉淀物溶解后进行相应的元素分析;提出一种根据沉淀物中的NH4^＋-N含量间接计算确定鸟粪石含量（即纯度）的分析方法.根据这种计算分析方法,分别得出了不同pH条件下以自来水（主要为地下水）和超纯水作为溶剂所合成的鸟粪石纯度,并对pH和Ca^2＋在鸟粪石形成过程中的影响进行了评估.结果表明,该计算分析方法能够有效实现对mAP沉淀法目标产物的定量分析,弥补了国内外目前普遍依靠XRD技术定性判断所得沉淀物中鸟粪石是否存在的缺陷.以超纯水作为溶剂时,使鸟粪石纯度〉90%的最佳pH范围在7.5-9.0,而以自来水为溶剂时,获得相同鸟粪石纯度最佳pH范围则是7.0-7.5.实际污水中常常含有相当数量的Ca^2＋,实施碱性条件（pH〉8.0）的mAP沉淀势必大幅降低鸟粪石的纯度.因此,对实际污水回收磷而言,mAP沉淀法的最优pH条件应控制在中性范围（〈8.0）以内.

关键词：鸟粪石 pH Ca2+ XRD 酸性溶解法元素分析

模拟评价亚硝化-厌氧氨氧化生物膜工艺中氧的消耗

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环境科学学报 2006年第5期26卷 798-802页

作者：郝晓地曹秀芹仇富国曹亚莉 m.C.m.van loosdrecht 北京建筑工程学院可持续环境生物技术研发中心北京100044 荷兰代尔夫特理工大学Kluyver生物技术实验室

前期模拟研究显示,溶解氧是控制亚硝化-厌氧氨氧化生物膜工艺的关键因子.因此,作为一个设计参数,曝气量在工程上便显得尤为重要.生物膜工艺曝气量取决于发生在生物膜内各种反应(硝化、常规反硝化及厌氧氨氧化)的耗氧与氧补偿以及生物膜... 详细信息

前期模拟研究显示,溶解氧是控制亚硝化-厌氧氨氧化生物膜工艺的关键因子.因此,作为一个设计参数,曝气量在工程上便显得尤为重要.生物膜工艺曝气量取决于发生在生物膜内各种反应(硝化、常规反硝化及厌氧氨氧化)的耗氧与氧补偿以及生物膜的厚度等.由于在生物膜内存在着基质扩散梯度,所以,通过试验方法确定净耗氧量十分困难,甚至难以实现.正因如此,数学模拟技术被用来评价这一在工艺设计和运行管理中具有实际意义的问题.模拟试验结果显示,不同的工艺及生物膜参数会导致不同的耗氧曲线.这些信息有助于亚硝化-厌氧氨氧化生物膜工艺的设计及运行.

关键词：厌氧氨氧化生物膜 COD氧化反硝化硝化耗氧量

Influence of curing conditions on the shrinkage behavior of three-dimensional printed concrete formwork

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1225-1236页

作者： m.BEKAERT K.van TITTELBOOm G.de SCHUTTER magnel-vandepitte Laboratory for structural Engineering and Building materials Department of Structural Engineering and Building MaterialsFaculty of Engineering and ArchitectureGhent UniversityGhent 60 B-9052Belgium

The use of three-dimensional(3D)printed concrete as formwork is becoming more widely applied within the ***,the technology is still not optimized and there are many reports of preliminary cracking during the curing of cast *** is believed to result from differential shrinkage between the printed and cast *** cracks(in the printed concrete or at the interface between the infill and printed concrete)form a preferential path for aggressive substances and can reduce the durability of the combined concrete *** ensure the desired service life of the structure,it is important that the differential shrinkage between cast and printed concrete is *** study investigated the effect of curing conditions on the differential shrinkage behavior of 3D and cast *** influence of prewetting of the dry-cured 3D printed formwork was also *** the experimental program,a vibrated and self-compacting concrete were used as cast *** 3D printed formwork was produced and combined with cast concrete to simulate a concrete *** formwork was cured for 1,7,or 28 d exposed to the air(relative humidity:60%or 95%)or submerged in *** length change of the combined elements was observed over 56 d after concrete casting and throughout the thickness of the *** show that increasing the curing period in dry conditions of the printed concrete leads to an expansion of the formwork on the first day after *** expansion leads to a non-uniform strain evolution throughout the curing period of the combined *** concrete formwork stored in wet conditions does not expand after the casting process but tends to show a decreasing linear deformation within the whole elements.

关键词： 3D concrete printing formwork shrinkage curing

Excess dietary Lys reduces feed intake, stimulates jejunal CCK secretion and alters essential and non‑essential blood AA profile in pigs

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1336-1346页

作者： maximiliano muller Elout van Liefferinge Alan Tilbrook Robert van Barneveld Eugeni Roura Centre for Nutrition and Food Sciences Queensland Alliance for Agriculture and Food InnovationThe University of QueenslandBrisbaneQueensland 4072Australia Laboratory of Animal Nutrition and Animal Product Quality(LANUPRO) Department of Animal Sciences and Aquatic EcologyGhent University339000 GhentFlandersBelgium Centre for Animal Science Queensland Alliance for Agriculture and Food Innovation and the School of Veterinary ScienceThe University of QueenslandBrisbaneQueensland 4072Australia SunPork Group BrisbaneQueensland 4009Australia

Background Commercial diets are frequently formulated to meet or exceed nutrient levels including those of lim-iting essential amino acids(AA)covering potential individual variations within the ***,the provision of dietary excess of AA,such as Lys,may lead to reduced appetite and growth in *** mechanisms modulat-ing these responses have not been extensively *** study evaluated the effect of Lys dietary excesses on performance and satiety biomarkers in post weaning *** Twenty-four pigs aged 21 d and weighing 6.81±0.12kg(mean±SEm)were individually housed and offered 1 of 4 dietary treatments for 3weeks:a diet containing a standardized ileal digestible Lys reaching 100%(T0),120%(T1),150%(T2)or 200%(T3)of the NRC(2012)*** the end of the experiment,blood samples from the cephalic vein of the T0 and T3 groups were obtained for AA *** addition,primary intestinal cultures from T0 pigs were used,following their humane killing,to evaluate the effect of Lys on gut hormone secretion and AA sensors gene expression under ex vivo *** Feed intake was linearly reduced(Pmetabotropic glutamate receptor 1 and the solute carrier family 7 member 2(Pmal jejunum tissues incubated with Lys at 20mmol/L when compared to the control(Lys 0mmol/L).Plasma Lys and Glu(Pmpared to T0 *** contrast,plasma levels of His,Val,Thr,Leu(Pm that excess dietary Lys inhibits hunger in ***,the results provide evidence of pre-and post-absorptive mechanisms modulating these *** dietary excesses should be nar-rowed,when possible,to avoid negative effects of

关键词： Amino acid Blood Cholecystokinin Feed intake Lysine Pig Satiety

Consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTECH 2024年第2期5卷 239-246页

作者： J.m.Lukasiewicz C.C.m.van de Wiel L.A.P.Lotz m.J.m.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically modified Organisms Directive(2001/18/EC)in the European *** the proposal of the European Commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques Consumer transparency Plant products

Changes in children’s cardiorespiratory fitness and body mass index over the course of the COVID‑19 pandemic:a 34‑month longitudinal study of 331 primary school children

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World Journal of Pediatrics 2024年第2期20卷 185-188页

作者： Gerald Jarnig Reinhold Kerbl mireille N.m.van Poppel Institute of Human movement Science Sport and HealthUniversity of GrazMozartgasse 148010 GrazAustria Department of Pediatrics and Adolescent medicine LKH Hochsteiermark8700 LeobenAustria

In late 2019,heavy restrictions were enforced on public activities worldwide to diminish the spread of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus[1].These restrictions,which included school closures and strictly limited sports and leisure opportunities,particularly impacted children and adolescents[2].Lifestyle changes in children and adolescents led to reduced physical activity levels[2,3],increased sedentary behavior[3,4],changes in eating habits,and changes in sleep habits[3].

关键词： respiratory acute children

Epidemiology of insertional and midportion Achilles tendinopathy in runners:A prospective cohort study

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Journal of Sport and Health Science 2024年第2期13卷 256-263页

作者： Wenbo Chen Kyra L.A.Cloosterman Sita m.A.Bierma-Zeinstra marienke van middelkoop Robert-Jan de Vos Department of Orthopaedic Surgery and Sports medicine Erasmus MC University Medical CenterRotterdam 3015GDthe Netherlands Department of General Practice Erasmus MC University Medical CenterRotterdam 3015GDthe Netherlands Department of Sports medicine Huashan HospitalFudan UniversityShanghai 200040China

Background:Achilles tendinopathy(AT)is a common problem among *** is only limited evidence for risk factors for AT,and most studies have not defined the AT *** study has compared the incidence and risk factors between insertional AT and midportion AT,though they are considered *** study aimed to assess incidence and risk factors of AT based on data from a large prospective *** secondary aim was to explore differences in risk factors between insertional and midportion ***:Participants were recruited from among registered runners at registration for running *** were completed at baseline,1 month before the event,1 week before the event,and 1 month after the *** concerning demographics,training load,registered events,and running-related injuries were collected at *** follow-up questionnaires collected information about new injuries.A pain map was used to diagnose midportion and insertional *** primary outcome was the incidence of *** logistic regression analysis was applied to identify risk factors for the ***:We included 3379 participants with a mean follow-up of 20.4 *** incidence of AT was 4.2%.The proportion of insertional AT was 27.7%and of midportion AT was 63.8%;the remaining proportion was a combined type of insertional and midportion *** had a significantly higher incidence(5%,95%confidence interval(95%CI):4.1%-6.0%)than women(2.8%,95%CI:2.0%-3.8%).AT in the past12 months was the most predominant risk factor for new-onset AT(odds ratio(OR)=6.47,95%CI:4.27-9.81).This was similar for both subcategories of AT(insertional:OR=5.45,95%CI:2.51-11.81;midportion:OR=6.96,95%CI:4.24-11.40).Participants registering for an event with a distance of 10/10.55 km were less likely to develop a new-onset AT(OR=0.59,95%CI:0.36-0.97)or midportion AT(OR=0.47,95%CI:0.23-0.93).Higher age had a significant negative association with insertional AT(OR=0.97,95%CI:0.9

关键词： Achilles tendon injury Incidence Risk factor Running-related injury

Deciding on life-saving treatment after a violent suicide attempt:an ethical case report

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General Psychiatry 2024年第2期37卷 289-291页

作者： Robert Wichers Hanna m Heller Sisco van Veen Department of Child and Adolescent Psychiatry&Psychosocial Care Amsterdam University Medical CenterLocation AMCAmsterdamThe Netherlands Amsterdam Public Health Mental Health programAmsterdamThe Netherlands Department of Hospital Psychiatry Amsterdam University Medical CenterLocation VUmcAmsterdamThe Netherlands Research Department 113 Suicide PreventionAmsterdamThe Netherlands Department of Psychiatry&Department of Ethics Law and HumanitiesAmsterdam University Medical CenterAmsterdamThe Netherlands GGZ inGeest mental Health Care AmsterdamThe Netherlands

To the editor:In the USA alone,there were 1.7 million suicide attempts in 2021.1 Although the majority of suicide attempts are not fatal,immediate medical attention is often necessary,especially when violent methods are used.2 These methods include jumping from heights,using a firearm,crashing a motor vehicle,and lying down or jumping in front of a moving object.

关键词： treatment editor alone

Velocity equation for grenades while impacting on dry sand media

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Defence Technology（防务技术） 2024年第5期35卷 168-173页

作者： martin macko Xuan Son Bui Kongsathit Phanthavong Duc Hung Pham van Gion Do van minh Do Jiri Skala University of Defence BrnoCzech Republic Le Quy Don Technical University Ha NoiViet Nam

This paper deals with the collision of sphere shape grenades with sand *** central issue of the article is the establishing of an empirical velocity equation of the grenade while impacting on sand that is used to solve motion equations of the mechanical mechanism inside the impact grenade *** paper focuses on impact velocities that are lower than 5 m s^(-1).An experiment was conducted to study the velocity of the grenade while impacting on dry sand.A high-speed camera video was used to capture the grenade *** grenade velocity in the impact process was generated from these video *** types of fitting curves are used to regress the velocity equation of the grenade while interacting with the sand media and the best-fitting model is *** result shows the regression curve has a high correlation with the experiment data for grenade velocities below 5 m s^(-1).The received regression equation is useful for analyzing the working ability of the inertial mechanism inside the impact grenade or analyzing and choosing the appropriate parameters of each part in the inertial mechanism to meet the required characteristics of the mechanism.

关键词： Dynamic response Impact velocity Impact grenade Low-velocity impact