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Use of Geochemical and Geophysical Techniques to Characterize and Prospect for Geothermal Resources and Hydrothermal Ore Deposits

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Journal of Earth Science 2015年第1期26卷 73-77页

作者： robert E.Criss Department of Earth and Planetary Sciences Washington UniversitySt.Louis 63130USA

Fluid-rock interactions alter the geochemical, isotopic, petrographic and physical character of host rocks, producing a permanent record of hydrothermal activity. Maps of altered rock properties show regular variations that disclose master geologic controls and delineate likely sites for geothermal and mineral resources. In many cases, geochemical and stable isotope data re- veal the origins of thermal fluids, and they can also provide estimates of reservoir temperatures and identify zones of fluid recharge.

关键词： geothermal system hydrothermal system geophysical prospecting geochemicalprospecting Mt. Lassen oxygen isotope.

Lygus hesperus （Heteroptera： Miridae） tolerates high concentrations of dietary nickel

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Insect Science 2007年第3期14卷 201-205页

作者： robert S. BOYD Department of Biological Sciences Auburn University Alabama USA

Nickel hyperaccumulator plants contain unusually elevated levels of Ni （〉 1 000 μg Ni/g）. Some insect herbivores, including Lygus hesperus （Western tarnished plant bug）, have been observed feeding on the California Ni hyperaccumulator Streptanthus polygaloides. This bug may be able to utilize S. polygaloides as a host either through its feeding behavior or by physiological tolerance of Ni. This experiment determined the Ni tolerance of L hesperus by offering insects artificial diet amended with 0, 0.4, 1, 2, 4.5, 10, 20 and 40 mmol Ni/L and recording survival. Survival varied due to Ni concentration, with diets containing 10 mmol Ni/L and greater resulting in significantly lower survival compared to the control （0 mmol Ni/L） treatment. Insects tolerated diet containing as much as 4.5 mmol Ni/L, a relatively elevated Ni concentration. I conclude that L hesperus can feed on S. polygaloides because it is Ni-tolerant, probably due to physiological mechanisms that provide it with resistance to plant chemical defenses including elemental defenses such as hyperaccumulated Ni.

关键词： elemental defense heavy metals herbivore defense hyperaccumulation metal tolerance nickel

Development of a symptom expectation questionnaire for minor head injury

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第6期12卷 499-502页

作者： robert FERRARI Deon LOUW Department of Medicine University of AlbertaEdmonton

Background and objective:Expectations and beliefs are important predictors of outcome following minor head *** this paper,the primary purpose is to develop a simple symptom expectation questionnaire for minor head injury for use in future research ***:An existing database of 179 injury-naive subjects who completed a 56-item checklist of expected symptoms for minor head injury was analyzed to determine which items could correctly identify an a priori case definition of an expecter (a subject who expected at least one of these symptoms would remain chronic following minor head injury).A total of six of the 56 items were found to be discriminatory,and these were tested in additional subject groups against the original ***:From the original database of 179 subjects completing a 56-item symptom expectation checklist,135 expected that at least one of the 56 symptoms would be chronic following minor head *** 135 expecters,however,all chose at least one of six items:headache,anxious or worried,depressed,difficulty concentrating,dizziness,and neck *** these six items,in two new groups of subjects,all those who endorsed one of the 56 symptoms as likely to be chronic following minor head injury (expecters) could also be identified on the 6-item ***:A shortened (6-item) symptom expectation checklist of commonly reported symptoms following minor head injury (headache,anxious or worried,depressed,difficulty concentrating,dizziness,and neck pain) correctly identifies subjects who expect that at least one symptom will be chronic following minor head injury (i.e.,an expecter).

关键词： Minor head iniurv Expectation Outcomes

Influence of MBBR carrier geometrical properties and biofilm thickness restraint on biofilm properties,effluent particle size distribution,settling velocity distribution,and settling behaviour

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Journal of Environmental Sciences 2022年第12期34卷 138-149页

作者： Raheleh Arabgol Peter A.Vanrolleghem robert Delatolla Department of Civil Engineering University of Ottawa161 Louis PasteurK1N 6N5 ONCanada ModelEAU Département de génie civil et de génie des eauxUniversitéLaval1065 av.de la MédecineQuébecCanada

The relatively poor settling characteristics of particles produced in moving bed biofilm reactor(MBBR)outline the importance of developing a fundamental understanding of the characterization and settleability of MBBR-produced *** influence of carrier geometric properties and different levels of biofilm thickness on biofilm characteristics,solids production,particle size distribution(PSD),and particle settling velocity distribution(PSVD)is evaluated in this *** analytical Vi CAs method is applied to the MBBR effluent to assess the distribution of particle settling *** method is combined with microscopy imaging to relate particle size distribution to settling *** conventionally loaded MBBR systems are studied at a similar loading rate of 6.0 g/(m^(2)·day)and with different carrier *** AnoxK^(TM)K5 carrier,a commonly used carrier,is compared to so-called thickness-restraint carriers,AnoxK^(TM)Z-carriers that are newly designed carriers to limit the biofilm ***,two levels of biofilm thickness,200μm and 400μm,are studied using AnoxK^(TM)Z-200 and Z-400 *** analysis confirms that K5 carriers demonstrated a significantly different biofilm mass,thickness,and density,in addition to distinct trends in PSD and PSVD in comparison with ***,in comparison of thickness-restraint carriers,Z-200 carrier results did not vary significantly compared to the Z-400 *** K5 carriers showed the lowest production of suspended solids(0.7±0.3 gTSS/day),thickest biofilm(281.1±8.7μm)and lowest biofilm density(65.0±1.5 kg/m^(3)).The K5 effluent solids also showed enhanced settling behaviour,consisting of larger particles with faster settling velocities.

关键词： MBBR Particle size distribution(PSD) Particle settling velocity distribution(PSVD) Settling behaviour ViCAs z-carriers

Tectonic Implications of Paleomagnetic Results From Upper Silurian Series Along the Hexi Corridor, Gansu, China

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Science China Chemistry 1993年第6期36卷 720-728页

作者：孟自芳 robert S. Coe Lanzhou Institute of Geology Academia Sinica Lanzhou 730000 PRC University of California at Santa Cruz USA

Characteristic directions of remanent magnetization of 38 samples from Upper Silurian Series (Hanxia Formation) along the Hexi Corridor passed fold test at a 99% confidence level. The corresponding paleopole is located at 45.1°N, 5.5°E (A_(95)= 4.7°, κ=25.1), close to the Late Permian pole for this area (41.4°N, 358.6°E; A_(95)= 4.3°, κ=26.6). However, there appears an obvious difference between paleolatitudes for these two stages (6°±). Based on paleomagnetic data, it can be deduced that the Hexi Corridor had probably been the western extension of the North China Block by the time of Late Silurian and kept being tectonically mobile compared with the principal parts of the North China Block. In addition, paleomagnetic data reveal that the Hexi Corridor experienced a southward displacement of about 600 km during the Late Paleozoic Era.

关键词： Hexi Corridor Upper Silurian Series southward displacement.

Nanosheet Chips Poised to Rescue Moore’s Law

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Engineering 2021年第12期7卷 1655-1656页

作者： robert Pollie 机构不详

The semiconductor industry reached a major milestone recently when IBM Research,the research and development division of International Business Machines Corporation(IBM),demonstrated what it billed as“the world’s first 2 nm chip”in May 2021(Fig.1)[1].The test chip uses a breakthrough technology called stacked nanosheets to achieve new levels of transistor density(transistors per square millimeter),paving the way for faster,more energyefficient semiconductors.

关键词： Rescue breakthrough faster

Subdifferentials of Distance Functions,Approximations and Enlargements

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Acta Mathematica Sinica,English Series 2007年第3期23卷 507-520页

作者： Jean-Paul PENOT robert RATSIMAHALO Department of Mathematics Faculty of Sciencesav.de l'Université BP 115564013 PA U CédexFrance Business Unit:Bank and Financials SODIFRANCE104 rue Castagnary75015 ParisFrance

In this work, we study some subdifferentials of the distance function to a nonempty nonconvex closed subset of a general Banach space. We relate them to the normal cone of the enlargements of the set which can be cons... 详细信息

关键词： Distance function Normal cone Regularization Subdifferential

Toward Ecological Economy

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Chinese Journal of Population,Resources and Environment 2007年第4期5卷 20-25页

作者： robert Costanza Gund Institute of Ecological Economics Rubenstein School of Environment and Natural Resources University of Vermont

Stories about the economy typically focus on Gross Domestic Product (GDP), jobs, stock prices, interest rates, retail sales, consumer confidence, housing starts, taxes, and assorted other indicators. We hear such thin... 详细信息

关键词：生态经济学 GDP GPI 循环经济环境保护

Machine Learning Produces Superhuman Chip Designs

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Engineering 2022年第3期8卷 7-9页

作者： robert Pollie Senior Technology Writer

First it was chess,then it was *** artificial intelligence(AI)is challenging human supremacy in a far more complex-and commercially significant-undertaking:designing *** June 2021,researchers at Google Brain(Google’s deep learning division)reported that they had devised a machine learning system that can produce manufacturable chip floorplans in a small fraction of the time taken by human experts.

关键词： Google artificial designing