510 research outputs found
Correction: Predicting the average charring rate of mass timber using data-driven methods for structural calculations
No full textThe original version of this article unfortunately contained an error in co-author’s name.
The given name and surname of the second author was swapped and published incorrectly. The author name would have been Yaxin Mo instead of Mo Yaxin.
Now, the author name is presented correctly with this correction article.
The original article has been corrected
Ji yu dan kong wei zhong xin de shi wen ya li chuan gan
No full textM.Phil.The nitrogen-vacancy center (NV center) in diamond is by far one of the most popular systems for sensing purposes. This can be attributed to its ease of optical detection at room temperature and its stability in nanostructures. In this work, we use the optically-detected magnetic resonance (ODMR) spectrum of the NV centers to sense hydrostatic pressures, quasi-hydrostatic pressures and beyond. By observing the shift of the two peaks of the ODMR spectrum, we show that the current NV centers retain most of their sensitivity at varying temperatures and pressures. On the other hand, the nanodiamond as an interesting material for pressure gradients detection enables us to experimentally establish a NV-based pressure mapping method, which would become a powerful technique for high pressure physics.High pressure physics needs to determine pressure and its distribution. Ruby is the most widely used sensor so far. Using the optical transitions of Ruby to measure pressure has typical drawbacks - the measurement is extremely sensitive to temperature and the size of the sensors is quite big. However, the metrology applications of NV in nanodiamond have stable performance at fluctuating temperatures. In addition, the NV center allows manual temperature correction. Compared to other pressure measurement techniques that are typically only sensitive to one point or part of the pressurized area, our results have spurred powerful new techniques to measure pressure and enable the implementation of spatial pressure mapping which could help improve sensing accuracy. Furthermore, we experimentally provide new perspective on the employment of the NV center, enabling it to be pressure sensor, and capable of analyzing the center's metrology applications under high pressure conditions.We can also use NV center to sense wavefunctions by examining its ¹³C hyperfine interactions under high and low pressures. According to the nature of the hyperfine interaction, it strongly depends on the relative positions of the nuclear and electron orbitals, so we have opportunity to monitor the effect of mechanical stress on the NV center. This is an extremely exciting attempt to measure the electronic spin density of NV center due to deformation of the diamond lattice.金剛石中的氮空位發光中心(NV 中心) 是迄今為止最常用的量子傳感系統之壹，原因是它在室溫下易於進行光學檢測並且具有穩定的納米結構。在這項工作中，我們通過NV 中心的光學探測磁共振(ODMR) 譜圖來感測靜水壓力，準靜水壓力以及更高壓力。通過觀察ODMR 譜圖中兩個共振峰的移動，我們發現NV 中心在不同的溫度和壓力下都可保持其大部分靈敏度。同時，作為壓力梯度檢測的有趣材料，納米金剛石使我們能夠通過實驗建立基於NV 的壓力測繪方法，這將成為高壓物理的強大技術。進行高壓物理的研究基本都需要對系統壓力的大小及分布進行判定。目前，在壓力檢測方面，紅寶石占據著主導地位。使用紅寶石的光學躍遷來測量壓力具有典型的缺點--測量結果極易受到溫度的影響，並且紅寶石作為傳感器其顆粒的尺寸也非常大。相比之下，納米金剛石中的NV 中心在波動的溫度下表現出穩定的性能，並且允許我們進行溫度校正。現有的壓力檢測手段通常僅對受壓範圍內的某壹點或某壹部分敏感，我們的測量可實現空間壓力測繪。這無疑激發了測量壓力的強大新技術，該技術有助於提高傳感精度。總體來看，我們在實驗上為NV 中心的使用提供了新的視角--使其成為壓力傳感器，並能夠分析中心在高壓條件下的計量應用。在這裏，我們還嘗試通過不同壓力下NV 中心與¹³C 的超精細相互作用來測量波函數。由於超精細相互作用強烈依賴核和電子軌道的相對位置，我們因此有機會監測機械應力對NV 中心的影響。利用金剛石晶格的變形來探測NV 的電子自旋密度，絕對是令人興奮的嘗試。Jiang, Yaxin = 基於氮空位中心的室溫壓力傳感 / 姜雅馨.Thesis M.Phil. Chinese University of Hong Kong 2019.Includes bibliographical references (leaves 90-106).Abstracts also in Chinese.Title from PDF title page (viewed on 06, January, 2021).Jiang, Yaxin = Ji yu dan kong wei zhong xin de shi wen ya li chuan gan / Jiang Yaxin
Sleep patterns and their association with depression and behavior problems among Chinese adolescents in different grades
No full text
We aimed to examine sleep patterns and their association with depression and behavior problems among Chinese adolescents in different grades. A cross-sectional study was conducted in 10 cities of mainland China. A total of 8,998 Chinese adolescents (49.3% males) aged 9-20 years completed a self-administered questionnaire that included questions on sleep patterns, depressive symptoms, behavior problems, and demographic characteristics. The percentage of adolescents who slept less than 7 hr on weekdays increased with grade, while the percentage of adolescents who slept less than 7 hr on weekends remained the same. The gap in sleep length between weekdays and weekends increased from 0.6 hr in grade 5 to 2.3 hr in Grade 12. The regression analysis showed that poor sleep habits were linked to greater emotional and behavioral problems. The associations of sleep length with those problems differed by symptom and grade. Sleeping less related to depression in all grades. More behavior problems were observed in primary school students who had less sleep and in senior high school students who had more sleep than their peers. The preference for going to bed late stably related to both adolescent depression and behavior problems in all grades, although it posed a greater risk for students in higher grades.</p
Root multiple ion uptake kinetics data for maize NAM founders, statistical code, and RhizoFlux hardware plans
No full textThis repository contains tabular data, R statistical code, protocols, and hardware plans associated with the following preprint:
A multiple ion-uptake phenotyping platform reveals shared mechanisms that affect nutrient uptake by maize roots
Marcus Griffiths, Sonali Roy, Haichao Guo, Anand Seethepalli, David Huhman, Yaxin Ge, Robert E. Sharp, Felix B. Fritschi, Larry M. York
bioRxiv 2020.06.15.153601; doi: https://doi.org/10.1101/2020.06.15.153601
Equipment designs.zip - Contains the hardware plans, parts lists, and experimental protocol
ImageJ_macro.zip - Contains scripts to use within ImageJ to segment images to calculate leaf area
manuscript supplementary.zip - Contains the actual supplemental figures and tables for the manuscript as well as RNAseq data
R code & raw data.zip - Contains a single .R text file containing all the R code to generate all the figures and and supplemental figures from the include raw data files
E-mail mdgriffiths or lmyork at noble.org with any questions.
Version 1 was used for the preprint.
Version 2 was used for the final manuscript
The effect of organic matter accumulation on phosphorus release in sediment of Chinese shallow lakes
No full textThe effects of organic matter in sediment on phosphorus release were studied by field investigations in eight Chinese shallow freshwater lakes with different trophic status and a laboratory experiment. The sediment organic matter content paralleled the trophic status, ranging from 6.1 to 173.0 g kg(-1) (dry weight), with the mean value of 63.1 g kg(-1) (dry weight). It was positively proportional to Soluble reactive phosphorus concentration in the interstitial water in a form of exponential function, but inversely related to the sediment Fe/P ratio. The sediment alkaline phosphatase activity was significantly related not only to the organic matter content (r = 0.829, P < 0.01, n = 120), but also to the soluble reactive phosphorus concentration in interstitial water (r = 0.454, P < 0.01, n = 42). In the laboratory experiment, the addition of organic matter (dry materials of an aquatic macrophyte) into the sediment significantly enhanced alkaline phosphatase activity and soluble reactive phosphorus release. However, in the treatment with organic matter added and aeration, this release was generally prevented in spite of an increase in APA. Hence, sediment organic matter can effectively accelerate phosphorus release by enzymatic hydrolysis and anaerobic desorption. The latter mechanism seems to be more important.The effects of organic matter in sediment on phosphorus release were studied by field investigations in eight Chinese shallow freshwater lakes with different trophic status and a laboratory experiment. The sediment organic matter content paralleled the trophic status, ranging from 6.1 to 173.0 g kg(-1) (dry weight), with the mean value of 63.1 g kg(-1) (dry weight). It was positively proportional to Soluble reactive phosphorus concentration in the interstitial water in a form of exponential function, but inversely related to the sediment Fe/P ratio. The sediment alkaline phosphatase activity was significantly related not only to the organic matter content (r = 0.829, P < 0.01, n = 120), but also to the soluble reactive phosphorus concentration in interstitial water (r = 0.454, P < 0.01, n = 42). In the laboratory experiment, the addition of organic matter (dry materials of an aquatic macrophyte) into the sediment significantly enhanced alkaline phosphatase activity and soluble reactive phosphorus release. However, in the treatment with organic matter added and aeration, this release was generally prevented in spite of an increase in APA. Hence, sediment organic matter can effectively accelerate phosphorus release by enzymatic hydrolysis and anaerobic desorption. The latter mechanism seems to be more important
Moving through the city. Redefine the relationship with the river through sustainable cruise tourism
No full textLAUREA MAGISTRALEI fiumi sono le risorse strategiche più importanti delle città contemporanee, e oggi sono diventati gli spazi più dinamici delle città, non solo con molteplici funzioni ecologiche, ma anche per uno sviluppo socio-economico sostenibile. Tuttavia, le aree di molo post-industriali occupano sempre la posizione vantaggiosa e su larga scala della città europea. Sotto la tendenza sempre più stretta dell'uso del suolo urbano, come riqualificare queste aree bianche urbane pone ulteriori sfide.
Il progetto si concentra su come utilizzare il processo di costruzione di una nuova industria del turismo per promuovere la trasformazione dell'area terminale post-industriale e rispondere a funzioni pubbliche complesse. Il Belgio ha una delle vie d'acqua interne più dense del mondo, ma la maggior parte delle vie d'acqua sono costruite con l'industria. Aalst è solo una di queste città, ma con i cambiamenti sociali, il declino della domanda di trasporto via acqua di Aalst ha portato ad aree portuali industriali abbandonate e vacanti, lasciando un vuoto nel centro della città. Anche se queste aree vuote possono essere riqualificate, la connessione materiale una volta stabilita tra le città sembra essere rotta. Come possiamo preservare la connessione tra queste memorie del sito e la città, tenendo conto delle inevitabili esigenze dello sviluppo urbano?
Lo scopo del progetto è quello di ricreare il flusso tra le città attraverso il turismo, creando così un nuovo spazio sul lungomare definito sia dai turisti in arrivo che dai residenti locali, e utilizzando il turismo sostenibile delle crociere fluviali per fornire un beneficio economico continuo. La crociera fluviale è una delle industrie in più rapida crescita nel turismo e l'Europa ha il secondo più grande mercato di crociere nel mondo. Sfruttando la sovrapposizione tra le esigenze di sviluppo urbano e quelle del turismo, l'edilizia urbana diventerà un progetto "cittadino" con benefici economici diretti, e le aree urbane un tempo abbandonate avranno anche l'opportunità di trasformare la loro identità. Come possiamo realizzare la trasformazione dell'identità dell'area portuale post-industriale?
La chiave per la trasformazione dell'identità regionale di DE KAAIEN sta nell'importanza del fiume urbano. Svolgere funzioni ecologiche, da canali di drenaggio urbano a spazi di adattamento urbano per il cambiamento climatico. Inoltre, diventa uno spazio pubblico veramente attivo, da inaccessibile area di scarico industriale a spazio pubblico culturale collegato alla città.Rivers are the most important strategic resources of contemporary cities, and today they have become the most dynamic spaces in cities, not only with multiple ecological functions, but also for sustainable socio-economic development. However, the post-industrial wharf areas always occupy the advantageous position and large-scale of the European city. Under the increasingly tight urban land use trend, how to redevelop these urban blank areas poses further challenges.
The project focuses on how to use the process of building a new tourism industry to promote the transformation of the post-industrial terminal area and respond to complex public functions. Belgium has one of the densest inland waterways in the world, but most waterways are built with industry. Aalst is just one of these cities, but with social changes, Aalst's declining demand for water transportation has resulted in abandoned and vacant industrial dock areas, leaving a void in the middle of the city. Although these blank areas can be redeveloped, the material connection once established between cities seems to be broken. How can we preserve the connection between these site memories and the city, taking into account the inevitable demands of urban development?
The aim of the project is to recreate the flow between cities through tourism, thereby creating a new waterfront space defined by both inbound tourists and local residents, and using sustainable river cruise tourism to provide an ongoing economic benefit. River cruising is one of the fastest-growing industries in tourism and Europe has the second largest cruising market in the world. By taking advantage of the overlap between urban development needs and tourism needs, urban construction will become a "citizen" project with direct economic benefits, and the once abandoned urban areas will also have the opportunity to transform their identity. How can we achieve the identity transformation of the post-industrial dock area?
The key to the transformation of the regional identity of DE KAAIEN lies in the importance of the urban river. Play ecological functions, from urban drainage canals to urban adaptation spaces for climate change. In addition, become a truly active public space, from inaccessible industrial waste areas to cultural public spaces connected to the city
Recommended from our members
University Belongingness Among Professional Doctoral Alumni in the US Transnational Education in China: A Mixed Methods Case Study
No full textThis mixed-methods case study investigates university belongingness among professional doctoral alumni within a US transnational education program in China. Guided by socialization theories, the study employed explanatory sequential design, beginning with an online survey and followed by in-depth interviews. The study addresses two main questions (RQ): RQ1: What are the key factors shaping the sense of belonging in transnational education programs? RQ2: How does the transnational nature of educational programs shape students’ sense of belonging toward the US and Chinese partner universities? The findings indicated that the academic reputation of partner universities, curriculum design, peer relationships, career background, and professional development were the primary influential factors of professional doctoral alumni's sense of belonging. Secondary influential factors included institutional culture, academic support, location and geopolitics, instructional methods, program requirements and structure, faculty-student interaction, staff-student relationships, educational background, interpersonal connections, and networking and collaboration in professional community, which interacted with primary factors to significantly affect alumni satisfaction and their sense of belonging toward both partner universities. The transnational setting itself enabled alumni to navigate multiple cultural and educational landscapes, thereby shaping a dual sense of belonging. This study addresses a gap in the literature on university belongingness among professional doctoral students and alumni in US transnational education in China. It contributes to the theoretical framework of socialization in contexts of transnational and professional community contexts, offering insights for administrators to enhance practice and policy, thereby improving the sense of belonging among transnational alumni. These insights are instrumental in guiding the design of structured student and alumni services that enhance the educational experience with both partner universities
Flux decline and concentration polarization during ceramic nanofiltration for polyethylene glycols, silica, and phosphate retention
No full textFor all pressure driven membranes, one of the main problems which hinders the membrane practical application is the permeate flux reduction due to the solute accumulation on the membrane surface. The most popular explanation for the flux decline supported by Bhattachajee &Bhattacharya (1993), contains two mechanisms: concentration polarization(CP) and fouling. The influence of CP is noteworthy in ceramic nanofiltration system. On the one hand, CP can influence the performance of membrane separation by decreasing the retention of the molecules. On the other hand, CP could have a desirable effect which can be used for membrane surface modification. In the past three or four decades, several different models have been used to verify the existence of CP or cake-enhanced CP(CECP) effect and try to quantify it. However, all these methods or models have their own limitations. Therefore, it is essential to build a new model or adjust the constants in the empirical model according to the practical situation. The flux decline behaviour of a ceramic nanofiltration membrane in the presence of polyethylene glycols (PEGs) and silica was investigated to examine the control factor in flux decline and calculate the CP factor in the filtration. The control factor in flux decline for PEGs is CP, while for silica, both CP and fouling are important. Based on the reversibility of CP and fouling, the Gel-polarization model together with the corresponded filtration method generated the modified Gel-polarization model which is suitable for calculating the fouling resistance and the osmotic pressure on the membrane. Sherwood formula is appropriate for calculating CP factor with calibrated constants. The flux decline behaviour, as well as the CECP model developed in this work, was used to investigate the possible CP&CECP during ceramic nanofiltration for phosphate retention. CECP model based on Sherwood relation can be used to investigate the influence of the fouling layer on CP with measured permeate flux, fouling mass, and an assumed/measured porosity of the fouling layer. Based on the CECP model analysis, lower crossflow velocity and cake layer porosity, larger permeate flux and fouling mass can produce a higher CECP factor. The change of permeability in phosphate retention can be used to calculate CP factors, however, the adsorption and electroviscous effect had influence on the accuracy of the results. CECP factor is not able to be measured by the change of permeability since the unstable fouling layer can influence the discovery of permeability decrease. The presence of calcium has a serious negative impact on phosphate retention probably due to the lower electrostatic repulsion of phosphate
- …
