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The benefits of corporate social responsibility (CSR) affect the entire supply chains a firm participates in. However, not every firm is in a position to force the implementation of CSR in its supply chains as some, especially small and medium-sized enterprises (SMEs), lack the necessary power. Chain directors can implement it acting as a principal, whereas the other chain members can act as agents.In the principal-agent framework, two main problems occur due to information asymmetry: adverse selection and moral hazard. This paper examines how a code of conduct (i.e. Social Accountability 8000) can help address the principal-agent problem, for SMEs, between chain directors and partners. The research method involves four case studies on CSR practices as implemented by Italian and Dutch SMEs within their supply chains.  相似文献   

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A chemical structure for humic substances   总被引:1,自引:0,他引:1  
Dedicated to Prof. Dr. H. D. Beckey on the occasion of his 70th birthday.  相似文献   

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用声级计对厦门大屿——鸡屿白鹭保护区的声环境进行了监测.结果表明:大屿岛保护区的噪声波动范围为42.9~64.6?dB,噪声等效声级(Leq)平均值为52.2?dB;鸡屿岛保护区的噪声波动范围为44.5~57.5?dB,噪声等效声级Leq平均值为50.9?dB,均略高于保护区评价噪声值50?dB的标准;噪声变化主要受轮...  相似文献   

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Animals rely on associative learning for a wide range of purposes, including danger avoidance. This has been demonstrated for several insects, including cockroaches, mosquitoes, drosophilid flies, paper wasps, stingless bees, bumblebees and honeybees, but less is known for parasitic wasps. We tested the ability of Psyttalia concolor (Hymenoptera: Braconidae) females to associate different dosages of two innately attractive host-induced plant volatiles (HIPVs), ethyl octanoate and decanal, with danger (electric shocks). We conducted an associative treatment involving odours and shocks and two non-associative controls involving shocks but not odours and odours but not shocks. In shock-only and odour-only trained wasps, females preferred on HIPV-treated than on blank discs. In associative-trained wasps, however, P. concolor’s innate positive chemotaxis for HIPVs was nullified (lowest HIPV dosage tested) or reversed (highest HIPV dosage tested). This is the first report of associative learning of olfactory cues for danger avoidance in parasitic wasps, showing that the effects of learning can override innate positive chemotaxes.  相似文献   

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Anencephaly in twin B was accompanied by elevated amniotic fluid alpha-fetoprotein (AFP) and a positive acetylcholinesterase (AChE) band on gel electrophoresis in both twin sacs, although twin A was normal. AChE results did not help distinguish the false positive AFP in this set of twins, implying that AChE may diffuse transamniotically as has been previously postulated for AFP. In light of the low concordance rate for neural tube defects in twins, patient counselling in this situation must include the information that AFP and AChE may be falsely elevated in normal twin when the other twin has a neural tube defect.  相似文献   

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本文认为模具结构设计是一个面向模具整体功能的装配设计过程.公式化描述了级进模结构特点,在分析并总结了现有“装配模型”的基础上,提出了一个支持级进模结构设计特点的“装配模型”.  相似文献   

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应用T-RFLP技术对珠江口中华白海豚主要栖息地的细菌菌群结构进行了分析,结果表明:在珠江口细菌多样性自西向东呈现"低-高-低"的态势,而且与其他海域相比具有较高的细菌多样性;MDS标序图与RELATE检验显示在该水域地理环境是影响细菌菌群结构和多样性的关键因素;通过BIOENV分析,表明温度、盐度和氧化还原电位组合起来对细菌菌群的影响较大;变形菌门和拟杆菌门的菌群是该水域的优势菌群,其中的某些机会致病菌可能会对中华白海豚种群的健康造成威胁。  相似文献   

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海洋性气候电子设备铝合金结构腐蚀防护研究   总被引:1,自引:4,他引:1  
通过对在海洋性气候环境条件下,电子设备铝合金结构腐蚀机理探讨研究以及腐蚀防护控制实践,选择确定电子设备铝合金材料、工艺和连接方法、表面防护系统及防腐蚀密封设计.将其纳入到电子设备的功能设计中,以避免单纯的工艺防护和事后补救措施,避免设计的随意性,从而使电子设备满足其寿命周期内各项功能.  相似文献   

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《资源调查与环境》2013,(4):257-260
本文利用卫星遥感影像数据进行线性构造解译,分析了福建大田—一都弧形构造及其对应的弧形影像特征,认为该弧形构造是在永安—晋江断裂带右行扭动作用下形成的;弧形构造及其特殊影像纹理特征具有表明断裂性质、判断不同方向断裂带发生先后次序的作用;弧形影像与其他断裂构造形成的线性影像叠合特征对指导找矿有重要意义。  相似文献   

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