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Rare Metals 2006年第5期25卷 501-511页

作者： Alexander A.Kodentsov jorma K.Kivilahti frans j.j.van loo Laboratory of Materials and Interface Chemistry Eindhoven University of TechnologyP.O.Box 5135600 MBEindhovenThe Netherlands Laboratory of Electronics Production Technology Helsinki University of TechnologyFIN-02150 EspooFinland

When a moderately stable phase is precipitated out during an intemal reaction, the behaviour of the penetrating atoms within the diffusion zone can be interpreted based on thermodynamic considerations. Evidence for “up-hill” diffusion of the penetrating species through the matrix towards the precipitation front during the intemal nitridation of Ni-Cr alloys at 1125℃ and 6000 bar of N2-pressure was predicted. Such behaviour of nitrogen is opposite to the boundary conditions in Wagner＇s description of internal reactions. A volume change associated with the precipitation reaction resulted in a stress gradient between the alloys surface and the intemal nitridation front. Stress relief occurred mainly by transport of nickel to the gas/metal interface. Pipe diffusion-controlled creep is the dominant stress accommodation mechanism during nitriding of dilute Ni-Cr alloys at 700℃ under a flowing NH3 ＋ H2 gas mixture.

关键词： nitridation nickel alloys thermodynamics diffusion internal precipitation

Fe_(3)O_(4)对黄铜矿在酸性硫酸铁溶液中铜溶解氧化还原反应的影响

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Transactions of Nonferrous Metals Society of China 2024年第6期34卷 1965-1975页

作者： Kolela j NYEMBWE Elvis FOSSO-KANKEU frans WAANDERS Martin MKANDAWIRE Didier K NYEMBWE Bhekie B MAMBA Water Pollution Monitoring and Remediation Initiatives Research Group School of Chemical and Minerals EngineeringFaculty of EngineeringNorth-West UniversityPotchefstroomSouth Africa Department of Mining Engineering College of Science Engineering and TechnologyUniversity of South AfricaFlorida Science CampusJohannesburgSouth Africa Department of Metallurgy Faculty of Engineering and Built EnvironmentUniversity of JohannesburgDoornfonteinJohannesburgSouth Africa Department of Chemistry School of Science and TechnologyCape Breton UniversityCanada School of Mining Metallurgy and Chemical EngineeringFaculty of Engineering and the Built EnvironmentUniversity of JohannesburgJohannesburgSouth Africa Institute for Nanotechnology and Water Sustainability College of Science Engineering and TechnologyUniversity of South AfricaFlorida Science CampusJohannesburgSouth Africa

由于钝化层的形成,黄铜矿(CuFeS_(2))在氧化条件下浸出通常具有溶解速率缓慢的特点。为了将黄铜矿浸出过程中的钝化效应降至最低并提高铜的回收率,研究了CuFeS_(2)在不同pH值(1.0、1.5和1.8)和温度(25和50℃)条件下浸出时,向Fe_(2)(SO_(... 详细信息

由于钝化层的形成,黄铜矿(CuFeS_(2))在氧化条件下浸出通常具有溶解速率缓慢的特点。为了将黄铜矿浸出过程中的钝化效应降至最低并提高铜的回收率,研究了CuFeS_(2)在不同pH值(1.0、1.5和1.8)和温度(25和50℃)条件下浸出时,向Fe_(2)(SO_(4))_(3)−H_(2)SO_(4)浸出剂中添加磁铁矿(Fe_(3)O_(4))对铜溶解速率的影响。结果表明,溶液pH值、电位和温度在溶解过程中起着关键作用。在pH 1.8、50℃和400 mV的条件下,Fe_(3)O_(4)−CuFeS_(2)混合体系中铜的回收率达到最大值(70%),而未添加Fe_(3)O_(4)时,CuFeS_(2)中铜的回收率较低(48%)。添加Fe_(3)O_(4)有助于维持较高的氧化还原值。添加Fe_(3)O_(4)还使活化能从79.04 kj/mol降低到53.69 kj/mol。这表明,当Fe_(3)O_(4)存在时,由于形成了更易溶解的中间体斑铜矿(Cu_(5)FeS_(4))和辉铜矿(Cu_(2)S),CuFeS_(2)更易被氧化。两种溶解过程都受到矿物表面的化学控制。此外,对浸出残渣的矿物学分析表明,当无Fe_(3)O_(4)存在时,作为表面钝化物的黄钾铁矾浓度较高。因此,添加Fe_(3)O_(4)减少了钝化层的形成,提升了铜的回收率。

关键词：黄铜矿溶解磁铁矿电偶钝化

Qualifying the suitability of living donor livers for pediatric liver transplantation:are we doing the right thing?

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Hepatobiliary Surgery and Nutrition 2023年第3期12卷 462-464页

作者： Henkjan j.Verkade frans C.j.Cuperus Aad P.van den Berg Division of Pediatric Gastroenterology and Hepatology Department of PediatricsUniversity of GroningenBeatrix Children’s HospitalUniversity Medical Center GroningenGroningenThe Netherlands Department of Gastroenterology and Hepatology University of GroningenUniversity Medical Center GroningenGroningenThe Netherlands

Over the last decades,liver transplantation has become the standard care for many forms of end-stage liver disease,both in adults and in *** prognosis after pediatric liver transplantation(pLT)has steadily increased up to a patient survival at 5 years of 85%and an estimated graft half life of 31 years(1,2).In the early days of pLT,the transplanted organ originated from deceased *** 1990,adult-to-child living donor liver transplantation(LDLT)programs have developed,which rapidly gained popularity,particularly in Europe and Asia(2,3).A major stimulus for LDLT has been the limited availability of deceased *** indications for liver transplantation have expanded,particularly for adult patients,at a higher rate than the availability of donor ***,the quality of donor organs has steadily declined,resulting in a decreased utilization of livers from deceased donors for transplantation(4).The limited availability of qualified deceased donor livers has further stimulated LDLT:in Europe,for example,the percentage of living donor organs used for pLT increased from 7%before 2000 to 40%since 2010(1).

关键词： Steatosis graft survival pediatric liver transplantation(pLT) patient survival

Reducing potassium deficiency by using sodium fertilisation

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Stress Biology 2022年第1期2卷 151-160页

作者： Sarah j.Thorne frans j.M.Maathuis Department of Biology University of SheffieldSheffield S102TNUK Department of Biology University of YorkYork YO15DDUK

Potassium(K)is the most abundant cation in the vast majority of *** is required in large quantities which,in an agronomic context,typically necessitates application of K in the form of potash or other K ***,the price of K fertiliser has risen dramatically,a situation that is paralleled by increasing K deficiency of soils around the globe.A potential solution to this problem is to reduce crop K fertiliser dependency by replacing it with sodium(Na)fertiliser which carries a much smaller price *** this paper we discuss the physiological roles of K and Na and the implications of Na fertilisation for crop cultivation and soil *** using greenhouse growth assays we show distinct growth promotion after Na fertilisation in wheat,tomato,oilseed and *** results also show that up to 60%of tissue K can be substituted by Na without growth *** on these data,simple economic models suggest that(part)replacement of K fertiliser with Na fertiliser leads to considerable savings.

关键词： Deficiency Fertiliser Nutrient Potassium Salinity Sodium

Challenges and prospects for consumer acceptance of cultured meat

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journal of Integrative Agriculture 2015年第2期14卷 285-294页

作者： Wim Verbeke Pierre Sans Ellen j van loo Department of Agricultural Economics Ghent UniversityGent B-9000 Belgium INP-ENV Toulouse Toulouse 31076 France UR1303 ALISS INRA Ivry-sur-Seine 94205 France

Consumer acceptance of cultured meat is expected to depend on a wide diversity of determinants ranging from technologyrelated perceptions to product-specific expectations, and including wider contextual factors like media coverage, public involvement, and trust in science, policy and society. This paper discusses the case of cultured meat against this multitude of possible determinants shaping future consumer acceptance or rejection. The paper also presents insights from a primary exploratory study performed in April 2013 with consumers from Flanders（Belgium）（n=180）. The concept of cultured meat was only known（unaided） by 13% of the study participants. After receiving basic information about what cultured meat is, participants expressed favorable expectations about the concept. Only 9% rejected the idea of trying cultured meat, while two thirds hesitated and about quarter indicated to be willing to try it. The provision of additional information about the environmental benefits of cultured meat compared to traditional meat resulted in 43% of the participants indicating to be willing to try this novel food, while another 51% indicated to be ‘maybe＇ willing to do so. Price and sensory expectations emerged as major obstacles. Consumers eating mostly vegetarian meals were less convinced that cultured meat might be healthy, suggesting that vegetarians may not be the ideal primary target group for this novel meat substitute. Although exploratory rather than conclusive, the findings generally underscore doubts among consumers about trying this product when it would become available, and therefore also the challenge for cultured meat to mimic traditional meat in terms of sensory quality at an affordable price in order to become acceptable for future consumers.

关键词： acceptance artificial attitude consumer cultured in vitro meat synthetic

Cavity enhanced absorption spectroscopy for N_2O detection at 2.86 μm using a continuous tunable color center laser

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Chinese Optics Letters 2003年第6期1卷 361-363页

作者：李少成于清旭 Maarten van Herpen Sacco te Lintel Hekkert frans j.M.Harren Department of Physics Dalian University of Technology Dalian 116024 Life Science Trace Gas Exchange Facility Department of Molecular and Laser Physics University of Nijmegen 6525 ED Nijmegen The Netherlands

The cavity enhanced absorption technique is applied to N2O detection around 2.86 μm using a continuous-wave color center laser. A high-finesse triangular ring cavity is used in this technology. Transmission through the cavity is obtained by jittering the cavity-length with a piezo on one of the cavity mirrors. A minimum detectable absorption coefficient of 2 × 10-6 cm-1 is achieved with a mirror reflectivity of 99.24%, corresponding to a N2O detection limit of 600 parts per billion.

关键词： Continuous wave lasers Gas detectors Nitrogen oxides

Structural, compositional and mineralogical characterization of carbonatitic copper sulfide: Run of mine, concentrate and tailings

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International journal of Minerals,Metallurgy and Materials 2019年第2期26卷 143-151页

作者： Kolela j Nyembwe Elvis Fosso-Kankeu frans Waanders Kasongo D Nyembwe Water Pollution Monitoring and Remediation Initiatives Research Group School of Chemical and Minerals Engineering Faculty of Engineering North-West University School of Mining Metallurgy and Chemical Engineering Faculty of Engineering and the Built Environment University of Johannesburg

The aim of this study was to determine the structural, compositional, and mineralogical composition of carbonatitic copper sulfide concentrator plant streams. Three samples, each from a different stream(run of mine(ROM), concentrate, and tailings) of a copper concentrator were characterized using various techniques, including stereomicroscopy, X-ray fluorescence, X-ray diffraction, Fourier transform infrared(FTIR) spectroscopy, scanning electron microscopy(SEM) in conjunction with energy-dispersive X-ray spectroscopy(EDS), and optical microscopy. The results reveal that each stream possesses its own unique compositional features. Carbonate minerals associated with calcite and dolomite, followed by quartz, remain the major minerals in both the ROM and tails streams. In the ROM stream, chalcopyrite appears to occur as veins within the carbonatite-hosting ore body. Mineral phase mutation was discovered in the tails stream because magnetite formerly identified in the ROM as the primary iron oxide had evolved into hematite. This metamorphosis was likely promoted by the concentration process. The concentration process was effective, upgrading the chalcopyrite content from 2 wt% in the ROM stream to 58 wt% in the concentrate stream; it was accompanied by bornite(4 wt%), anilite(3 wt%), and digenite(2.5 wt%). In addition, the concentrate stream exhibited properties distinctive from those of the other streams. The FTIR analysis showed the existence of a sulfide group related to the chalcopyrite mineral. Free chalcopyrite grains were observed in the concentrate by SEM analysis, and their mineral presence was supported by the EDS analysis results. All characterization techniques corresponded well with each other regarding the structure, chemistry, and composition of the samples.

关键词： chalcopyrite mineral characterization phase mutation concentrate streams

High-quality-factor tantalum oxide nanomechanical resonators by laser oxidation of TaSe2

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Nano Research 2015年第9期8卷 2842-2849页

作者： Santiago j. CartamiI-Bueno Peter G. Steeneken frans D. Tichelaar Efren Navarro-Moratalla Warner j. Venstra Ronald van Leeuwen Eugenio Coronado Herre S.j. van der Zant Gary A. Steele Andres Castellanos-Gomez Kavli Institute of Nanoscience Delft University of Technology Lorentzweg 1 2628 CJ Delft The Netherlands Kavli Institute of Nanoscience Delft University of Technology National Centre for HREM Lorentzweg 1 2628 CJ Delft The Netherlands Instituto Ciencia Molecular (ICMol) Univ. Valencia C/Catedrdtico Jos@ Beltrdn 2 E-46980 Paterna Spain

Controlling the strain in two-dimensional （2D） materials is an interesting avenue to tailor the mechanical properties of nanoelectromechanical systems. Here, we demonstrate a technique to fabricate ultrathin tantalum oxide nanomechanical resonators with large stress by the laser oxidation of nano-drumhead resonators composed of tantalum diselenide （TaSe2）, a layered 2D material belonging to the metal dichalcogenides. Before the study of their mechanical properties with a laser interferometer, we verified the oxidation and crystallinity of the freely suspended tantalum oxide using high-resolution electron microscopy. We demonstrate that the stress of tantalum oxide resonators increases by 140 MPa （with respect to pristine TaSe2 resonators）, which causes an enhancement in the quality factor （14 times larger） and resonance frequency （9 times larger） of these resonators.

关键词： TaSe2,tantalum oxide,mechanical resonators,laser oxidation,optical interferometer,high quality factor

Evolutionary dynamics of leucine‐rich repeat receptor‐like kinases and related genes in plants:A phylogenomic approach

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journal of Integrative Plant Biology 2014年第7期56卷 648-662页

作者： Tao Shi Hongwen Huang Michael j.Sanderson frans E.Tax Department of Ecology and Evolutionary Biology University of Arizona School of Life Sciences Lanzhou University South China Botanical Garden the Chinese Academy of Sciences Department of Molecular and Cellular Biology University of Arizona School of Plant Sciences University of Arizona

Leucine-rich repeat （LRR） receptor-like kinases （RLKs）, evolutionarily related LRR receptor-like proteins （RLPs） and receptor-like cytoplasmic kinases （RLCKs） have important roles in plant signaling, and their gene subfamilies are large with a complicated history of gene duplication and loss. In three pairs of closely related lineages, including Arabidopsis thaliana and A. lyrata （Arabidopsis）, Lotus japonicus, and Medicago truncatula （Legumes）, Oryza sativa ssp. japonica, and O. sativa ssp. indica （Rice）, we find that LRR RLKs comprise the largest group of these LRR-related subfamilies, while the related RLCKs represent the smal est group. In addition, comparison of orthologs indicates a high frequency of reciprocal gene loss of the LRR RLK/LRR RLP/RLCK subfamilies. Furthermore, pairwise comparisons show that reciprocal gene loss is often associated with lineage-specific duplication（s） in the alternative lineage. Last, analysis of genes in A. thaliana involved in development revealed that most are highly conserved orthologs without species-specific duplication in the two Arabidopsis species and originated from older Arabidopsis-specific or rosid-specific duplications. We discuss＆amp;nbsp;potential pitfal s related to functional prediction for genes that have undergone frequent turnover （duplications, losses, and domain architecture changes）, and conclude that prediction based on phylogenetic relationships wil likely outperform that based on sequence similarity alone.

关键词： Domain architecture evolution gene duplication and loss leucine-rich repeat receptor-like kinases leucine-rich repeat receptor-like proteins receptor-like cytoplasmic kinases

Nuclear Cardiology, The Basics 2nd ed. 2008

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