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Information sharing in procurement occurs in rich and varied industry contexts in which managerial decisions are made and organizational strategy is formulated. We explore how information sharing ought to work in procurement contexts that involve investments in inter-organizational information systems (IOS) and collaborative planning, forecasting and replenishment (CPFR) practices. How and under what circumstances does a firm that plays the role of a supply chain buyer decide to share information on key variables, such as point-of-sale consumer demand data with its supplier, up the supply chain? This is a key issue that crosses the boundary between supply chain management and information systems (IS) management. The answers that we provide are based on our use of a game-theoretic signaling model of buyer and supplier strategy in the presence of uncertainties about final consumer demand. We also explore the connection between operational costs that are associated with the firm’s information sharing and information withholding strategies. Our results provide normative guidance to supply chain buyers about how to interpret different demand uncertainty scenarios to improve their decisions and generate high value. From the IS management perspective, we show the impacts on the firm of different information sharing approaches that are made possible by present day technologies. 相似文献
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Mahmood Razzaghi Masoud Kasiri-Asgarani Hamid Reza Bakhsheshi-Rad Hamid Ghayour 《矿物冶金与材料学报》2021,28(1):168-178
A type of polymer/ceramic coating was introduced on a magnesium-based nanocomposite, and the nanocomposite was evaluated for implant applications. The microstructure, corrosion, and bioactivity of the coated and uncoated samples were assessed. Mechanical alloying followed by sintering was applied to fabricate the Mg–3Zn–0.5Ag–15NiTi nanocomposite substrate. Moreover, different contents of poly(lactic-co-glycolic acid) (PLGA) coatings were studied, and 10wt% of PLGA content was selected. The scanning electron microscopy (SEM) images of the bulk nanocomposite showed an acceptable homogenous dispersion of the NiTi nanoparticles (NPs) in the Mg-based matrix. In the in vitro bioactivity evaluation, following the immersion of the uncoated and coated samples in a simulated body fluid (SBF) solution, the Ca/P atomic ratio demonstrated that the apatite formation amount on the coated sample was greater than that on the uncoated nanocomposite. Furthermore, assessing the corrosion resistance indicated that the coatings on the Mg-based substrate led to a corrosion current density (icorr) that was considerably lower than that of the substrate. Such a condition revealed that the coating would provide an obstacle for the corrosion. Based on this study, the PLGA/hardystonite (HT) composite-coated Mg–3Zn–0.5Ag–15NiTi nanocomposite may be suitably applied as an orthopedic implant biomaterial. 相似文献
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本文记述了伊朗北部GoLestan省的食虫虻种类(双翅目:食虫虻科),总计调查鉴定了食虫虻科的10亚科( ApocLeinae,AsiLinae,Dasypogoninae,BrachyrhopaLinae,Laphriinae,Laphystiinae,Leptogastrinae,Brachyrho-paLinae,Stenopogoninae和Stichopogoninae)17属21种。 相似文献
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Immunogenicity of formaldehyde and binary ethylenimine inactivated infectious bursal disease virus in broiler chicks 下载免费PDF全文
Mudasser Habib Iftikhar Hussain Hamid Irshad Zong-zhao Yang Jiang-bing Shuai Ning Chen 《浙江大学学报(自然科学英文版)》2006,7(8):660-664
Infectious bursal disease virus (IBDV) was inactivated by two different chemicals—formaldehyde and binary ethylenimine (BEI). Formaldehyde was used at 0.1% and 0.2%, while BEI was used at concentrations of 0.001 and 0.002 mol/L. These four vaccines were tested for their efficiency in generating humoral immune response in different groups of broiler chicks. Both BEI-inactivated vaccines gave relatively higher antibody titers and were almost twice as efficient as formaldehyde-inactivated ones. 相似文献
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Effects of heat treatment on the intermetallic compounds and mechanical properties of the stainless steel 321-aluminum 1230 explosive-welding interface 下载免费PDF全文
Mohammadreza Khanzadeh Gharah Shiran Gholamreza Khalaj Hesam Pouraliakbar Mohamma dreza Jandaghi Hamid Bakhtiari Masoud Shirazi 《矿物冶金与材料学报》2017,24(11):1267-1277
The effects of heat treatment on the microstructure and mechanical properties of intermetallic compounds in the interface of stainless steel 321 explosively bonded to aluminum 1230 were investigated in this study. Experimental investigations were performed by optical microscopy, scanning electron microscopy, and microhardness and shear tensile strength testing. Prior to heat treatment, increasing the stand-off distance between samples from 1 to 2.5 mm caused their interface to become wavy and the thickness of intermetallic layers to increase from 3.5 to 102.3 μm. The microhardness increased from HV 766 in the sample prepared at a stand-off distance of 1 mm to HV 927 in the sample prepared at a stand-off distance of 2.5 mm; in addition, the sample strength increased from 103.2 to 214.5 MPa. Heat treatment at 450℃ for 6 h increased the thickness of intermetallic compound layers to 4.4 and 118.5 μm in the samples prepared at stand-off distances of 1 and 2.5 mm, respectively. These results indicated that increasing the duration and temperature of heat treatment decreased the microhardness and strength of the interface of explosively welded stainless steel 321-Al 1230 and increased the thickness of the intermetallic region. 相似文献
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Polyaniline was synthesized chemically in an acidic medium in the presence of Ammonium Peroxydisulphate (APS) as an oxidizing agent. PANI(Polyaniline) nanocomposites were prepared in the presence of various amount of carbon nanotube and zinc oxide (from 1 to 5 wt%) by solution casting method. The free-standing film of polyaniline and its nanocomposites were obtained by vaporization of solvent content. The composition, morphology and structure of the polymer and the nanocomposites were characterized by Fourier transform infrared spectroscopy FT-IR spectra, scanning electron microscopy (SEM) image and XRD pattern. In addition, thermal stability was studied by TGA analysis, electrical conductivity was measured by four-point probe technique and mechanical properties were studied by tensile strength test. The characteristic FTIR peaks of PANI were found to shift to lower wave number in nanocomposites due to the formation of H-bonding. XRD results revealed that the crystallinity of PANI was more noticeable after addition of nano-ZnO, while the intensity of the peaks increased by the addition of ZnO nanoparticles. Furthermore, TGA results showed that the decomposition of the nanocomposite was less than that of pure polyaniline which confirms the successful fabrication of products. Young''s modulus and strength at break point were increased in the case of the nanocomposite, in addition, the electrical conductivity of the PANI/ZnO nanocomposite film was found to be smaller than that of the PANI film while CNTs increase the conductivity of polyaniline. 相似文献
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Hamid Ashrafi Rahmatollah Emadi Mohammad Hosein Enayati 《矿物冶金与材料学报》2014,21(7):711-719
The aim of this study was to produce bulk nanocrystalline Al/Al12(Fe,V)3Si alloys by mechanical alloying (MA) and subsequent hot pressing (HP) of elemental powders. A nanostructured Al-based solid solution was formed by MA of elemental powders for 60 h. After HP of the as-milled powders at 550℃ for 20 min, the Al12(Fe,V)3Si phase was precipitated in a nanocrystalline Al matrix. Scanning electron microscopy (SEM) images of the bulk samples represented a homogeneous and uniform microstructure that was superior to those previously obtained by rapid solidification-powder metallurgy (RS-PM). Nanostructured Al-8.5Fe-1.3V-1.7Si and Al-11.6Fe-1.3V-2.3Si alloys ex-hibited high HV hardness values of~205 and~254, respectively, which are significantly higher than those reported for the RS-PM counter-parts. 相似文献
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Stevanin G Santorelli FM Azzedine H Coutinho P Chomilier J Denora PS Martin E Ouvrard-Hernandez AM Tessa A Bouslam N Lossos A Charles P Loureiro JL Elleuch N Confavreux C Cruz VT Ruberg M Leguern E Grid D Tazir M Fontaine B Filla A Bertini E Durr A Brice A 《Nature genetics》2007,39(3):366-372
Autosomal recessive hereditary spastic paraplegia (ARHSP) with thin corpus callosum (TCC) is a common and clinically distinct form of familial spastic paraplegia that is linked to the SPG11 locus on chromosome 15 in most affected families. We analyzed 12 ARHSP-TCC families, refined the SPG11 candidate interval and identified ten mutations in a previously unidentified gene expressed ubiquitously in the nervous system but most prominently in the cerebellum, cerebral cortex, hippocampus and pineal gland. The mutations were either nonsense or insertions and deletions leading to a frameshift, suggesting a loss-of-function mechanism. The identification of the function of the gene will provide insight into the mechanisms leading to the degeneration of the corticospinal tract and other brain structures in this frequent form of ARHSP. 相似文献