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dryland agriculture and rangeland restoration priorities in Afghanistan

journal of Arid Land 2015年第3期7卷 391-402页

作者： Michael j jACOBS Catherine A SCHLOEdER Philip d TANIMOTO Texas Agri Life Research Department of Ecosystem Science & Management2138TAMUCollege StationTX 77843-2138USA Oikos Services LLCFortineMT 59918USA Conservation Imaging Inc.AuburndaleMassachusetts 02466USA

Afghanistan is threatened by rangeland degradation.A quantitative visual analysis of Google Earth Imagery was used to systematically locate,characterize and quantify the current extent of rangelands in Afghanistan degraded as a consequence of dryland *** data were used in conjunction with dryland agriculture locations to establish a climate envelope comprised by temperature and mean annual precipitation to create a geographical mask known to contain dryland *** this mask we created a grid of 100 km2 cells that we analyzed individually to access dryland agriculture *** limits to sustainable dryland agriculture and areas of high restoration priority were also assessed as was the distribution of rain-fed agriculture with respect to the location of traditional migration routes for extensive livestock *** extents of agriculture in Afghanistan,at both upper and lower elevations,correlated most closely with mean annual temperature（MAT） at the upper elevation limits,and with mean annual precipitation（MAP） at the lower elevation *** total,dryland agriculture comprised 38,980 km2 of former native *** was highest in the northwestern,northern and northeastern provinces of Herat,Badghis,Faryab,jawzjan,Sar-e-Pul,Samangan,Balkh,Baghlan,Kunduz,Takhar and Badakhshan,with the highest percentage of conversion occurring in *** MAP value of 〈400 mm is perceived by farmers as the current climatic limit to sustainable dryland agriculture across the northern regions of the *** this MAP value,approximately 27,677 km2 of converted rangeland met the need for restoration *** projections indicate that Afghanistan will become warmer and drier in the coming *** consequence of this trend is that the MAP threshold of 〈400 mm to sustainable dryland agriculture will become obsolete in the coming *** of currently converted rangelands is needed to restore critical grazing area

关键词： degradation climatic trends extensive livestock production dryland agriculture rangeland restoration

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THERMOdYNAMICS OF CERIUM CARBIdE Fe_4Ce_4C_7 IN STEEL

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Acta Metallurgica Sinica(English Letters) 1998年第2期11卷 150-156页

作者： j.Z.Zhang d.Z.Li Guizhou Univ of Technology Guiyang China

The thermodynamics and the properties of the cerium carbide Fe4 Ce4 C7 in steel have been studied by means of metallography, electron microprobe, X-ray diffraction technique and electrolytic separation. The main results obtained can be summarized as follows: The cerium carbide CeC2 can be precipitated in cast steel and distributed along the grain boundaries. Heat treating the steel as austenite, the CeC2 transformed into ternary compound Fe4Ce4 C7, its thermodynamics of formation in steel being expressed as: ac exp(6400/T-6. 28), where 1015Kd ac 0.126. Fe4Ce4C7 in steel is primitive tetragonal, anisotmpic in polarized light, opaque in dark field and a little greyer than iron matrix in bright field. Its Vickers hardness is about 420kg/mm2 (annealed) and 750kg/mm2 (quenched). This phase in steel is stable in basic and organic solutions and can be seperated from the matrix by electrolysis. Moreover, the LaC2 in steel can not be transformed into Fe-La-C ternary compound in present investigation.

关键词： cerium carbide electrolytic separation thermodynamics

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Synchronous improvement of mechanical properties and stress corrosion resistance by stress-aging coupled with natural aging pre-treatment in an Al-Zn-Mg alloy with high recrystallization fraction

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journal of Materials Science & Technology 2022年第26期121卷 40-51页

作者： d.Zhang H.C.jiang Z.j.Cui d.S.Yan Y.Y.Song L.j.Rong CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shandong Key Laboratory of Advanced Aluminum Materials and Technology Binzhou 256606China

Enhancing the strength of Al-Zn-Mg alloys is critical to the weight-lightening of structural components in the application of high-speed trains and aerospace industries,while high stress corrosion cracking(SCC)susceptibility of Al-Zn-Mg alloys(especially the alloy with high recrystallization fraction)with high strength makes it *** this study,the influence of tensile stress-aging coupled with natural aging pre-treatment on the mechanical properties and SCC resistance of Al-Zn-Mg alloy with high recrystallization fraction has been *** results show that tensile stress-aging at 160℃can inhibit the dissolution of clusters/Guinier-Preston(GP)zones formed during long-term natural aging pre-treatment,which increases the number density of matrix precipitates(MPts),narrow the width of precipitate free zone(PFZ),and dramatically improve the mechanical properties of the experimental Al-Zn-Mg ***,the precipitation of the high density of MPts within the matrix will assume a large number of solute atoms during artificial aging,which will reduce the supplement of solute atoms to grain *** a result,the volume of anodic active grain boundary precipitates(GBPs)and the content of free solute atoms at grain boundaries are reduced,which reduces the possibility of initial nucleation and propagation of SCC *** coupled treatment method proposed in this study proves efficient in resolving the contradiction between the strength and SCC resistance in Al-Zn-Mg alloy.

关键词： Al-Zn-Mg alloy Natural aging Stress-aging Precipitates Stress corrosion cracking

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In search of effective therapies to overcome resistance to Temozolomide in brain tumours

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Cancer drug Resistance 2019年第4期2卷 1018-1031页

作者： Kaouthar Bouzinab Helen Summers jihong Zhang Malcolm F.G.Stevens Christopher j.moody Lyudmila Turyanska Neil R.Thomas Pavel Gershkovich Marianne B.Ashford Emily Vitterso Lisa C.d.Storer Richard Grundy Tracey d.Bradshaw School of Pharmacy University of NottinghamNottingham NG72RDUK School of Chemistry University of NottinghamNottingham NG72RDUK School of Physics and Astronomy University of NottinghamNottingham NG72RDUK Advanced drug delivery Pharmaceutical SciencesR&DAstraZenecaMacclesfield SK104TFUK School of Medicine Queen’s Medical CentreUniversity of NottinghamNottingham NG72UHUK.

Glioblastoma multiforme is the most common and lethal brain *** current standard of care includes Temozolomide(TMZ)***,inherent and acquired resistance to TMZ thwart successful *** direct repair protein methylguanine dNA methyltransferase(MGMT)removes the cytotoxic O6-methylguanine(O6-MeG)lesion delivered by TMZ and so its expression by tumours confers *** mismatch repair(MMR)is essential to process O6-MeG adducts and MMR-deficiency leads to tolerance of lesions,resistance to TMZ and further dNA *** this article,two strategies to overcome TMZ resistance are discussed:(1)synthesis of imidazotetrazine analogues-designed to retain activity in the presence of MGMT or loss of MMR;(2)preparation of imidazotetrazine-nanoparticles to deliver TMZ preferably to the brain and tumour *** promising results encourage belief in a future where better prognoses exist for patients diagnosed with this devastating disease.

关键词： Brain cancer temozolomide-resistance analogues drug delivery apoferritin

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Predictive approach of heterogeneous catalysis

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National Science Review 2018年第5期5卷 633-635页

作者： jean-Marie Basset jérémie d.A.Pelletier King Abdullah University of Science and Technology

‘Predictive catalysis’ or ‘catalysis by design’ has recently advanced heterogeneous catalysis by using the conceptual tool of surface fragments [1] such as ‘surface organometallic fragments’(SOMF)or ‘surface coordination fragments’(SCF) to achieve and understand a presumed catalytic cycle (see Fig. 1).One or several fragments of the molecule

关键词： SCF CR CO EXAFS

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Impaired lysosomes in the retinal pigment epithelium play a central role in the degeneration of the neuroretina

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Neural Regeneration Research 2023年第12期18卷 2697-2698页

作者： Rebecca d.Miller j.Arjuna Ratnayaka Clinical and Experimental Sciences Faculty of MedicineUniversity of SouthamptonSouthamptonUK

Lysosomes are highly dynamic, single membranebound compartments that are critical for maintaining cellular homeostasis. These organelles, which appear to vary between 200 nm–1 μm in diameter, originate from the maturation of endocytic vesicles and via the enrichment of newly synthesized lysosomal proteins in the trans-Golgi network.

关键词： critical dynamic degeneration

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3d Flow Past Transonic Turbine Cascade SE 1050-Experiment and Numerical Simulations

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journal of Thermal Science 2013年第4期22卷 311-319页

作者： d.imurda j.Fürst M.Luxa Institute of Thermomechanics AS CR v.v.i.Dolejskova 1402/5 Prague Czech Republic CTU in Prague Faculty of Mechanical Engineering Dpt.of Technical MathematicsKarlovo Náměstí 13 Prague Czech Republic

This paper is concerned with experimental and numerical research on 3d flow past prismatic turbine cascade SE1050 （known in QNET network as open test case SE1050）. The primary goal was to assess the influence of the inlet velocity profile on the flow structures in the interblade channel and on the flow field parameters at the cascade exit and to compare these findings to results of numerical simulations. Investigations of 3d flow past the cascade with non-uniform inlet velocity profile were carried out both experimentally and numerically at subsonic （M2 = 0.8） and at transonic （M2 = 1.2） regime at design angle of incidence. Experimental data was obtained using a traversing device with a five-hole conical probe. Numerically, the 3d flow was simulated by open source code OpenFOAM and in-house code. Analyses of experimental data and CFd simulations have revealed the development of distinctive vortex structures resulting from non-uniform inlet velocity profile. Origin of these structures results in increased loss of kinetic energy and spanwise shift of kinetic energy loss coefficient distribution. differences found between the subsonic and the transonic case confirm earlier findings available in the literature. Results of CFd and experiments agree reasonably well.

关键词： blade cascade vortex structures transonic flow CFd

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A Factor decomposing Model of Water Use Efficiency at Sector Level and Its Application in Beijing

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journal of Systems Science & Complexity 2016年第2期29卷 405-427页

作者： LIU Xiuli HEWINGS j d Geoffrey CHEN Xikang WANG Shouyang Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China. Regional Economics Applications Laboratory University of Illinois607 S.Mathews#318UrbanaIL61801USA

The paper explores the contribution of different factors affecting water use efficiency(WUE) of each sector and explores ways to improve WUE.A new Multi-Sector and Multi-Factors Logarithmic Mean divisia Index(MLMdI) decomposition method was developed that enabled the identification of WUE by sector into 11 factors in terms of their order of *** application to Beijing at the 19 sector level was made for the period between 2002–*** water conservation effects of six measures proposed during the 12th-Five-Year-Plan of Beijing were *** was found that,to decrease the transferred out and export of agriculture products and increasing water prices would be the top two most effective measures to promote water *** the adjustment of direct water use structure would contribute in less significant way,the adjustment of industrial structure would have a negative effect.

关键词： Beijing factor decomposition method water use efficiency.

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Long-term corrosion evolution associated with the structural heterogeneities of an Fe-based amorphous coating in H_(3)BO_(3)solution at various temperatures

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journal of Materials Science & Technology 2023年第9期140卷 233-248页

作者： d.B.Wang j.Wu j.P.Cui Q.Wang T.R.Li W.Emori S.d.Zhang j.Q.Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchCASShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Key Laboratory of Biorheological Science and Technology Ministry of EducationCollege of BioengineeringChongqing UniversityChongqing400044China School of Materials Science and Engineering Sichuan University of Science and EngineeringZigong 643000SichuanChina

Understanding the long-term corrosion behavior of neutron absorber materials in H_(3)BO_(3)solution is crucial for the materials applications in spent fuel *** this paper,long-term corrosion evolution for 180 d in relation to the structural heterogeneities of an Fe-based amorphous coating(AMC)in H_(3)BO_(3)solution at various temperatures was systematically *** indicate that the coating corrosion could be divided into three distinct ***,the corrosion resistance increased owing to the thickening and composition evolution of the passive ***,the corrosion rate was kept almost constant in the second stage,which connected with the steady state of the passive ***,the corrosion resistance of coating reduced gradually owing to the initiation and penetration of local-ized ***,it was revealed that the localized corrosion was initiated at the relatively Cr-depleted amorphous matrix in the deep pores of the *** could be attributed to the synergy of Cr-depletion and occlusive effect in the deep pores during long-term *** the elevation of temperature,the localized corrosion was enhanced due to the accumulation of the H+in the pores to swiftly reach the critical conditions for passive film *** work provides insights into the long-term corrosion mechanism of Fe-based AMCs in H_(3)BO_(3)solution and offers meaningful contributions to the design of new corrosion resistant neutron absorbing coatings for spent fuel storage applications.

关键词： AMC Boric acid EIS Long-term corrosion Temperature

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Creation and annihilation phenomena of electron and positron pairs in an oscillating field

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Chinese Physics B 2021年第7期30卷 151-156页

作者： M jiang d d Su N S Lin Y j Li School of Science China University of Mining and TechnologyBeijing 100083China State Key Laboratory for Geomechanics and deep Underground Engineering China University of Mining and TechnologyBeijing 100083China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

The combination of an oscillating and a static field is used to study the creation and annihilation phenomena during the pair creation *** time evolution,spatial density and momentum distribution of the created particles for a fermionic system are presented,which demonstrate that with the increasing static field intensity,the number of the created particles experiences a distinguishable decrease in every period of the oscillating field,which is caused by the annihilation phenomena between the created electrons and positrons.

关键词： pair creation computational quantum field theory strong laser field

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