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Photonics Research 2019年第6期7卷 I0026-I0033页

作者： ANDREW M.ARMSTRONG BRIANNA A.KLEIN ANDREW A.ALLERMAN ALBERT G.BACA mary h.crawford JACOB PODKAMINER CARLOS R.PEREZ MIChAEL P.SIEGAL ERICA A.DOUGLAS VINCENT M.ABATE FRANCOIS LEONARD Sandia National Laboratories Albuquerque New Mexico 87185 USA Current address: 3M Corporate Research Labs St. Paul Minnesota 55144 USA Sandia National Laboratories Livermore California 94550 USA

AlGaN-channel high electron mobility transistors(hEMTs) were operated as visible-and solar-blind photodetectors by using GaN nanodots as an optically active floating gate. The effect of the floating gate was large enough to switch an hEMT from the off-state in the dark to an on-state under illumination. This opto-electronic response achieved responsivity >10^8 A∕W at room temperature while allowing hEMTs to be electrically biased in the offstate for low dark current and low DC power dissipation. The influence of GaN nanodot distance from the hEMT channel on the dynamic range of the photodetector was investigated, along with the responsivity and temporal response of the floating gate hEMT as a function of optical intensity. The absorption threshold was shown to be controlled by the AlN mole fraction of the hEMT channel layer, thus enabling the same device design to be tuned for either visible-or solar-blind detection.

关键词： photodetectors high electron mobility transistors

USING EARLY-STAGE ASSESSMENT TO REDUCE ThE FINANCIAL RISKS AND PERCEIVED BARRIERS OF SUSTAINABLE BUILDINGS

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Journal of Green Building 2010年第2期5卷 114-128页

作者： Renuka Ranaweera Robert h.crawford Faculty of Architecture Building and PlanningThe University of MelbourneVictoria3010Australia

For sustainable buildings to become mainstream they must demonstrate not only improved environmental performance but also financial performance,benefiting both end users and *** perceived financial constraints and risks are often major barriers to sustainable *** paper discusses the application of a new tool that formalizes the traditionally intuitive-based early-stage decision making processes and assesses the potential for creating a financially feasible best-practice sustainable building across a range of environmental,social and economic parameters,using the limited data available at the outset of a *** considers the total cost of ownership,demonstrating the link between the recurrent and capital costs.A detailed feasibility assessment of those areas where greatest potential for improving environmental and financial performance exists can then be carried out,saving a considerable amount of time,money and effort otherwise spent on looking at all possible strategies for achieving a sustainable *** approach also identifies areas where incorporating environmental strategies might be financially risky,reassuring investors and developers by reducing investment *** reducing some of these risks and perceived barriers to sustainable building development,it is hoped that clients and investors will be further encouraged to adopt a more sustainable approach to their building projects.

关键词： sustainable buildings environmental performance financial performance life cycle approach early stage assessment

Determination of Physical, Mechanical and Fire Retardancy Properties of Innovative Particleboard Made from Corn Stalk (Zea mays L.) Particles

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Journal of Renewable Materials 2024年第10期12卷 1729-1756页

作者： Lilik Astari Benoit Belleville Kenji Umemura Alex Filkov Barbara Ozarska Robert h.crawford School of Agriculture Food and Ecosystem SciencesThe University of MelbourneMelbourne3121Australia Research Center for Biomass and Bioproducts National Research and Innovation AgencyBogor16911Indonesia Research Institute of Sustainable humanosphere Kyoto UniversityKyoto611-0011Japan School of Agriculture Food and Ecosystem SciencesThe University of MelbourneCreswick3363Australia Faculty of Architecture Building and PlanningThe University of MelbourneMelbourne3010Australia

The demand for particleboard is increasing along with economic and population ***,two major barriers to the manufacture of particleboard are a shortage of raw materials(woodchips)and the emission of formaldehyde from conventional *** by-products such as corn stalks contain an abundance of renewable lignocellulosic *** study evaluates the effect of citric acid as a natural adhesive and fire retardant addition on the physical,mechanical,and fire retardancy properties of particleboards fabricated from corn stalks.A cost-effective and inorganic salt,calcium carbonate,was tested to enhance the fire *** dihydrogen phosphate was also considered as a comparative *** with the addition of calcium carbonate was pretreated with sodium *** particleboards were pressed for 10 min at 200℃.Japanese Industrial Standard JIS A 5908:2022 was used as the benchmark for the physical and mechanical *** retardancy was dynamically tested by simulating a Bushfire Attack Level of 19 kW/m^(2).The particleboard with 25 wt%citric acid had superior mechanical properties and complied with the JIS A 5908 standard for Type 13 base *** with the addition of calcium carbonate(5%and 10%)showed significantly delayed pyrolysis time.

关键词： Particleboard corn stalk fire retardancy citric acid mechanical properties

Mating system and genetic diversity of a rare desert legume Ammopiptanthus nanus (Leguminosae)

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Journal of Systematics and Evolution 2009年第1期47卷 57-66页

作者： Daniel J crawford Department of Ecology and Evolutionary Biology and the Natural History Museum and Biodiversity Research CenterThe University of Kansas

Ammopiptanthus nanus is an endangered evergreen shrub endemic to the deserts of central Asia and plays an important role in delaying further desertification. We examined allozyme variation and AFLP diversity in A. nanus populations and investigated the mating system of this species using progeny arrays assayed for poly-morphic allozyme loci. Mating system analysis in the Keyi’eryongke’er population showed low levels of out-crossing, and strong inbreeding depression. Low levels of genetic variation were detected at both population (allozyme, Pp=14.0%, A=1.14, he=0.031; AFLP, Pp=14.5%, Shannon’s information index I=0.063) and species (allozyme, Pp=21.1%, A=1.21, he=0.040; AFLP, Pp=20.9%, I=0.083) levels; while moderate genetic differentiation existed among populations, as indicated by allozymes (GST=0.081) and AFLP (GST=0.151-0.193). Founder effect, bottlenecks in evolutionary history, the mixed mating system and co-ancestry may have influenced the level of genetic diversity in A. nanus. Markers of both types provide new insights for conservation management, indicating that the Biao’ertuokuoyi and Keyi’eryongke’er populations should be given priority for in situ conservation and regarded as seed sources for ex situ conservation.

关键词： AFLP allozyme Ammopiptanthus conservation endangered plant genetic structure outcrossing rate

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慢性稳定型心绞痛最佳医疗方案

药学情报通讯 1991年第3期9卷 24-27,44页

作者： Michael h.crawford 周静美国得州大学健康科学中心心脏病学

心绞痛的发作是由于心肌的供氧量和耗氧量之间平衡失调所致。慢性稳定型心绞痛通常起因于冠状血管粥样硬化损伤,导致心肌缺血。然而由于血管过度扩张或痉挛可急剧限制冠脉血流量,同时也可引起心绞痛。这种混合型心绞痛已经得到许多的关... 详细信息

心绞痛的发作是由于心肌的供氧量和耗氧量之间平衡失调所致。慢性稳定型心绞痛通常起因于冠状血管粥样硬化损伤,导致心肌缺血。然而由于血管过度扩张或痉挛可急剧限制冠脉血流量,同时也可引起心绞痛。这种混合型心绞痛已经得到许多的关注,但是在慢性稳定型心绞痛的病人中,心绞痛的发作可能只占约20％。

关键词：心绞痛慢性

Clonal Characterization of Bone Marrow Derived Stem Cells and Their Application for Bone Regeneration

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International Journal of Oral Science 2010年第3期2卷 127-135页

作者： Shobha Mareddy Ross crawford Institute of health and Biomedical Innovation Queensland University of Technology

Tissue engineering allows the design of functionally active cells within supportive bio-scaffolds to promote the development of new tissues such as cartilage and bone for the restoration of pathologically altered tissues. however, all bone tissue engineering applications are limited by a shortage of stem cells. The adult bone marrow stroma contains a subset of nonhematopoietic cells referred to as bone marrow mesenchymal stem cells （BMSCs）. BMSCs are of interest because they are easily isolated from a small aspirate of bone marrow and readily generate singlecell-derived colonies. These cells have the capacity to undergo extensive replication in an undifferentiated state ex vivo. In addition, BMSCs have the potential to develop either in vitro or in vivo into distinct mesenchymal tissues,including bone, cartilage, fat, tendon, muscle, and marrow stroma. Thus, BMSCs are an attractive cell source for tissue engineering approaches. however, BMSCs are not homogeneous and the quantity of stem cells decreases in the bone marrow in aged population. A sequential loss of lineage differentiation potential has been found in the mixed culture of bone marrow stromal cells due to a heterogenous popu- lation. Therefore, a number of studies have proposed that homogenous bone marrow stem cells can be generated from clonal culture of bone marrow cells and that BMSC clones have the greatest potential for the application of bone regeneration in vivo.

关键词： bone morrow stem cell meserichymal clonalculture regenerative medicine differentiation

Simulation of Fragment Impact on Multi-Layer Targets Using Contact Method

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Transactions of Tianjin University 2006年第B9期12卷 152-157页

作者： crawford John E Karagozian & Case 2550 N.Hollywood WaySuite 500BurbankCA 91505USA

Cased explosives generate highly energetic fragments as their casing breaks up. Due to the complexity of casing fragment related behavior such as embedment, perforation and ricochet, it may be insufficient to use equivalent triangular pressure loading in fragment impact simulations. This simplified method may over- or under-predict the target response. Recently, a procedure using contact techniques has been proposed to overcome such difficulties. It has been shown that the new method has the inherent capability in modeling the multi-piece and multi-hit fragment impact problems in a more realistic way. To investigate the applicability of the proposed method to simulations involving multi-layer penetration, the selected problems of fragment impact on multi-layer targets are described in this paper. It is demonstrated that this method is capable of predicting the complicated multi-layer structural response caused by fragment impact and penetration. Modeling procedures and some technical issues are also discussed.

关键词： contact finite element fragment impact multi-layer penetration simulation

Development of Light Weight Structures to Provide Blast-Resistant Designs

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Transactions of Tianjin University 2006年第B9期12卷 16-21页

作者： crawford John E Karagozian & Case 2550 N.hollywood Way #500BurbankCA 91505USA

In the past, blast-resistant designs for structures were often constructed with massive type structural systems, which relied more on brute strength than on finesse to achieve the required blast resistance. however, structures composed of COLD-FORMED steel components, such as sheet metal and metal studs, have shown great promise in providing blast resistance with the added benefits of low cost and ease of construction. Some examples of using such structures to provide containment for package handling facilities (PhF) are described in the paper for situations where blast containment is needed, such as a potential package bomb being discovered during the package vetting process. Results from tests and analytic data are used to illustrate aspects of design peculiar to such types of applications. Designs for specific capacities of PhF are described.

关键词： blast containment package handling facility hardened design light weight structures COLD-FORMED steel structures

多普勒超声心动图对主动脉瓣返流定量方法的研究

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中国超声医学杂志 1991年第1期 43-45页

作者：简文豪,高雪英,高代薇,Kent L.Richards,Michael S.Lujan,Michael h.crawford 北京部队总医院北京部队总医院北京部队总医院美国德州大学医疗中心及VA医院美国德州大学医疗中心及VA医院美国德州大学医疗中心及VA医院

彩色多普勒(CDFI)、常规多普勒、CDFI与常规多普勒联合应用,总计35项指标测定返流分数(RF),与x线左室造影及心导管指示剂稀释法对51例患者检查结果对照表明,CDFI的定量最准确,10/14项指标的r值达0.802～0.976,P<0.005。

关键词：主动脉瓣返流心尖血流连续波多普勒 CDFI 定量方法

Double aortic arch and nasogastric tubes: A fatal combination

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World Journal of Gastroenterology 2008年第16期14卷 2590-2592页

作者： Julia Massaad Kelly crawford Emory University School of Medicine Division of Digestive Diseases

Double aortic arch is a common form of complete vascular ring that encircles both the trachea and the esophagus, and presents with various respiratory and esophageal symptoms, usually in the pediatric population. We present a case of double aortic arch in an adult patient that manifested as massive upper gastrointestinal bleeding after prolonged nasogastric intubation.

关键词： Nasogastric tubes Aortoesophageal fistula Gastrointestinal bleeding Double aortic arch Vasculardngs