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Crystalline compounds for remediation of rare-earth fission products:A review

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Journal of Rare Earths 2022年第3期40卷 365-380,I0001页

作者： Saehwa Chong brian J.Riley Zayne J.Nelson Pacific Northwest National Laboratory RichlandWA99352USA

Rare earth(RE)-containing crystals have been investigated as media for the immobilization of RE fission products from nuclear waste *** reprocessing of spent nuclear fuel,fission products including REs,alkalis,and alkaline earths released from the *** viable option to immobilize the RE fission products is to incorporate them into chemically durable crystalline phases in specific waste *** study summarizes the crystal structures and synthesis methods of six RE-containing compounds that have applications in remediation of RE fission *** compounds include oxyapatite(AE_(2)RE_(8)(SiO_(4))_(6)O_(2)),oxychloride(REOCl),borosilicate(RE_(3)BSi_(2)O_(10)),pyrochlore(RE_(2)M_(2)O_(7)),monazite(REPO_(4)),and perovskite(REMO_(3))where AE denotes alkaline earth metals and M denotes transition *** review provides an overview of literature on the usage of these six compounds for immobilizing RE fission products and summarizes different synthesis methods for producing these *** of structural parameters with different REs in each compound are also discussed.

关键词： Rare-earth compounds Nuclear waste forms Crystal structures Synthesis of rare-earth compounds

Numerical Research on Effect of Sudden Cross-Section Expansion on Detonation Initiation

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Journal of Thermal Science 2022年第5期31卷 1575-1590页

作者： JIA Xiongbin ZHAO Ningbo MAXWELL brian CHEN Xiang ZHENG Hongtao College of Power and Energy Engineering Harbin Engineering UniversityHarbin150001China Department of Mechanical and Aerospace Engineering Case Western Reserve UniversityCleveland44106USA

Numerical simulation has been performed to investigate the DDT(Deflagration-to-Detonation Transition)mechanism by solving fully compressible reactive flow for hydrogen/air mixtures in tube with sudden cross-section *** results reveal the acceleration action of abrupt cross-section on DDT,which is validated by comparing the run up distance and time with corresponding long annular tube and single *** discussion of flow field variations finds that the DDT process in cross-section abrupt tube can be divided into three stages(flame acceleration,transition to detonation,and detonation propagation stages respectively)according to different flame ***,it is found that formation of vortex could accelerate DDT by promoting turbulent mixing of hot products and cold *** comparative analysis on DDT characteristics of cross-section abrupt tube with different annular gap lengths shows that different mechanisms dominate in the single tube *** conclusions in present study support the cross-section abrupt tube as a means to enhance DDT and provide an alternative potential in practical pre-detonation initiator and pulse detonation engine applications.

关键词： deflagration to detonation transition numerical simulation cross-section abrupt tube turbulent mixing flame acceleration

ODS & Modal Testing Using a Transmissibility Chain

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Sound & Vibration 2018年第2期52卷 2-7页

作者： brian Schwarz Patrick McHargue Mark Richardson Vibrant Technology Inc. Centennial CO United States

In this paper, we show how Operating Deflection Shapes (ODS’s) andmode shapes can be obtained experimentally from measurements thatare made using only two sensors and two short wires to connect them to amulti-channel acquisition system. This new test procedure is depicted inFigure 1. Not only is the equipment required to do a test much more costeffective, but this method can be used to test any sized test article, especiallylarge ones.

关键词： Fourier spectrum (DFT) Auto power spectrum (APS) Crosspower spectrum (XPS) Frequency Response Function (FRF) OperatingDeflection Shape (ODS) Experimental Mode Shape (EMA Mode) OperationalMode Shape (OMA Mode) Modal Assurance Criterion (MAC) ShapeDifference Indicator (SDI)

CRISPR ribonucleoprotein-mediated genetic engineering in plants

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Plant Communications 2021年第2期2卷 38-50页

作者： Yingxiao Zhang brian Iaffaldano Yiping Qi Department of Plant Science and Landscape Architecture University of MarylandCollege ParkMD 20742USA Institute for Bioscience and Biotechnology Research University of MarylandRockvilleMD 20850USA

CRISPR-derived biotechnologies have revolutionized the genetic engineering field and have been widely applied in basic plant research and crop *** used Agrobacterium-or particle bombardment-mediated transformation approaches for the delivery of plasmid-encoded CRISPR reagents can result in the integration of exogenous recombinant DNA and potential off-target *** efficiency is also highly dependent on the design of the expression cassette and its genomic insertion *** engineering using CRISPR ribonucleoproteins(RNPs)has become an attractive approach with many advantages:DNA/transgene-free editing,minimal off-target effects,and reduced toxicity due to the rapid degradation of RNPs and the ability to titrate their dosage while maintaining high editing *** RNP-mediated genetic engineering has been demonstrated in many plant species,its editing efficiency remains modest,and its application in many species is limited by difficulties in plant regeneration and *** this review,we summarize current developments and challenges in RNPmediated genetic engineering of plants and provide future research directions to broaden the use of this technology.

关键词： CRISPR RNP genetic engineering genome editing transgene free

WATER CONSERVATION: OBSERVATIONS FROM A HIGHER EDUCATION FACILITY MANAG EMENT P ERSP ECTIVE

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Journal of Green Building 2016年第3期11卷 162-182页

作者： Anthony Cupido Laura Steinberg brian Baetz Mohawk College HamiltonON.CanadaL8N 3T2 Department of Civil Engineering Syracuse UniversitySyracuseNY13244 Department of Civil Engineering McMaster UniversityHamiltonON.CanadaL8S 4L7.

Sustainable or green building practices have been adopted by most higher educa-tion institutions for their new campus buildings,major renovations and daily *** paper provides a synthesis of opinions and existing practices related to water conservation in institutional green buildings of member institutions of APPA(formerly the Association of Physical Plant Administrators).A specific focus regard-ing waterless urinals and their operation was attempted.A web-based survey and follow-up one-to-one interviews were utilized to extract information and data from these industry *** survey evaluated the institution’s use of policy related to sustainable building practices and focused on their approaches to water *** preferences are provided and barriers to some water conser-vation practices and approaches have been *** challenges are evident,particularly as they relate to waterless *** is clear that higher educa-tion institutions are engaging in water conservation practices across Canada and the United *** work contributes to a foundation for future research and analysis related to best-management practices for water conservation in the higher education sector.

关键词： water conservation higher education LEED® rainwater harvesting waterless urinals policy

Osteogenesis of Adipose-Derived Stem Cells

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Bone Research 2013年第2期1卷 133-145页

作者： brian E. Grottkau Yunfeng Lin Department of Orthopaedic Surgery MassGeneral Hospital for Children and the Pediatric Orthopaedic Laboratory for Tissue Engineering and Regenerative MedicineHarvard Medical SchoolBostonMassachusettsUSA

Current treatment options for skeletal repair, including immobilization, rigid fixation, alloplastic materials and bone grafts, have significant limitations. Bone tissue engineering offers a promising method for the repair of bone deficieny caused by fractures, bone loss and tumors. The use of adipose derived stem cells （ASCs） has received attention because of the self-renewal ability, high proliferative capacity and potential of osteogenic differentiation in vitro and in vivo studies of bone regeneration. Although cell therapies using ASCs are widely promising in various clinical fields, no large human clinical trials exist for bone tissue engineering. The aim of this review is to introduce how they are harvested, examine the characterization of ASCs, to review the mechanisms of osteogenic differentiation, to analyze the effect of mechanical and chemical stimuli on ASC osteodifferentiation, to summarize the current knowledge about usage of ASC in vivo studies and clinical trials, and finally to conclude with a general summary of the field and comments on its future direction.

关键词： adipose derived stem cells osteogenesis bone tissue engineering osteogenic differentiation

Fast Fourier Transform:A Niche,but Critical Strategy in Optimizing Impression Evidence

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Journal of Forensic Science and Medicine 2018年第4期4卷 192-196页

作者： brian Dalrymple Department of Forensic Science Laurentian UniversitySudburyCanada

The evolution from film to digital as the recording medium for forensic imaging has extended the reach of forensic photographers,both in original capture and postphotography *** of fingermarks and footwear impressions are routinely obstructed by substrates displaying intrusive color and *** backgrounds are frequently sufficiently intrusive as to prevent the analysis and comparison of the images to known *** techniques such as Fast Fourier Transform(FFT)in postphotography processing can optimize the signal-to-noise ratio to a greater degree than was ever possible when film was the recording ***,unwanted backgrounds can be removed or diminished in Photoshop with techniques such as background subtraction and channel *** strategies,however,are dependent on either physical removal of the evidence impression to obtain a second image of the obstructive pattern or on differences in color between the impression and the offending *** is unique in its ability to optimize the image signal to noise ratio by suppressing the obstructive background,in that it is not reliant on color,and is not applied in the spatial domain.

关键词： Fast Fourier Transform image pro premier postphotography digital optimization

Strategies to improve fiber utilization in swine

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Journal of Animal Science and Biotechnology 2013年第2期4卷 112-123页

作者： brian J Kerr Gerald C Shurson USDA-ARS-National Laboratory for Agriculture and the Environment University of Minnesota

Application of feed processing methods and use of exogenous feed additives in an effort to improve nutrient digestibility of plant-based feed ingredients for swine has been studied for decades. The following review will discuss several of these topics, including： fiber characterization, impact of dietary fiber on gastrointestinal physiology, energy, and nutrient digestibility, mechanical processing of feed on fiber and energy digestibility, and the use of exogenous enzymes in diets fed to growing pigs. Taken together, the diversity and concentration of chemical characteristics that exists among plant-based feed ingredients, as well as interactions among constituents within feed ingredients and diets, suggests that improvements in nutrient digestibility and pig performance from mechanical processing or adding exogenous enzymes to diets fed to swine depends on a better understanding of these characteristics, but also relating enzyme activity to targeted substrates. It may be that an enzyme must not only match a target substrate（s）, but there may also need to be a ＇cocktail＇ of enzymes to effectively breakdown the complex matrixes of fibrous carbohydrates, such that the negative impact of these compounds on nutrient digestibility or voluntary feed intake are alleviated. With the inverse relationship between fiber content and energy digestibility being well described for several feed ingredients, it is only logical that development of processing techniques or enzymes that degrade fiber, and thereby improve energy digestibility or voluntary feed intake, will be both metabolically and economically beneficial to pork production.

关键词： Energy Enzymes Fiber Growing-finishing pigs Nutrient digestibility Processing

Field scanner design for MUSTANG of the Green Bank Telescope

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Science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 2091-2096页

作者： CHENG JingQuan LI Yang LI XinNan MASON brian National Radio Astronomy Observatory Charlottesville 22903 USA Nanjing Institute of Astronomical Optics and Technology Nanjing 210042 China

MUSTANG (Multiplex SQUID TES Array at Ninety GHz) is a bolometer camera for the Green Bank Telescope (GBT) working at a frequency of 90 *** detector has a field of view of 40 *** cancel out random emission change from atmosphere and other sources,requires a fast scanning reflecting system with a few arcminute *** this paper,the aberrations of an off-axis system are *** condition for an optimized system is *** an optimized system,as additional image transfer mirrors are introduced,new aberrations of the off-axis system may be reintroduced,resulting in a limited field of *** this paper,different scanning mirror arrangements for the GBT system are analyzed through the ray tracing *** include using the subreflector as the scanning mirror,chopping a flat mirror and transferring image with an ellipse mirror,and chopping a flat mirror and transferring image with a pair of face-to-face paraboloid *** system analysis shows that chopping a flat mirror and using a well aligned pair of paraboloids can generate the required field of view for the MUSTANG detector system,while other systems all suffer from larger off-axis aberrations added by the system *** spot diagrams of the well aligned pair of paraboloids produced are only about one Airy disk size within a scanning angle of about 3 arcmin.

关键词： antenna optics off-axis linear astigmatism coma reflector scanner