废干电池制取锰锌铁氧体过程中锰的测定

利用废干电池制取锰锌铁氧体过程中需要准确测定锰含量。以硝酸银作催化剂，采用硫酸亚铁铵滴定法测定锰含量，并对氧化剂用量、硝酸银用量、铁锌的影响等进行了试验。结果表明，该法操作简单、快速准确，锰回收率为98．7％-102．8％。     

Explaining the Role of Perceived Risk,Knowledge, Price,and Cost in Dry Fish Consumption Within the Theory of Planned Behavior

ABSTRACT

The general purpose of this study is to explore the influence of perceived risk, knowledge, price, and cost of dry fish consumption in Bangladesh using the general framework from the theory of planned behavior (TPB). The field experiments were performed in Bangladesh with a convenience sample of 558 respondents. Multiple regression analysis was used to investigate the relationship among perceived risk, knowledge, price, and cost and TPB constructs. The findings showed that attitude, norms, and procedural knowledge emerge as the key determinants of intention, whereas intention, attitude, norms, and perceived risk have effects on the dry fish consumption frequency. Perceived behavioral control, price, and cost had no significant effect on intention and consumption behavior. The proposed TPB and the extended model both fit the data well and proved the expectations of this study in a promising way. The study found that people are more concerned about potential long-term risk to their family and others. Therefore, management attention should focus on reducing risks which consumers may face through producing safe and hazard-free dry fish.     

Is farming enough in mountain areas? Farm diversification in the Pyrenees

The continuity of farming in mountain areas in Europe is at severe risk and its future faces manifold uncertainties. Mountain farms are immersed in a long-term process of reorganization. Farm diversification plays a prominent role in this process of adjustment and reallocation. However, little work has been done explicitly on the role farm diversification plays in the current structural changes occurring. In order to fill this void, the nature of farm diversification has been examined in the Pyrenees, where four different typologies of farms have been identified: absence of diversification, agricultural diversification, farmland diversification and finally farm labour diversification. These typologies reflect a gradation along which the farm diversification practices are applied to more aspects of the farm household. Throughout this gradation farming is increasingly marginalised. Finally, it is argued that the endorsement of policy measures stimulating farm diversification in mountain regions should be cautiously considered, since there is high risk of encouraging further agricultural abandonment.     

A study of the relationships between the time charter and spot freight rates

A time charter contract is a shipping contract that allows for freight rate risk avoidance and hedging. Defining the relationship between time charter and spot freight rates will illuminate the fluctuation mechanism of the spot freight market. In this article, three types of dry bulk ships – Capsize, Panamax and Supramax – are chosen to investigate the relationship between time charter and spot freight rates and to analyse the price discovery function of time charter contracts. A vector error correction model is developed, and an impulse response function is used to analyse the influence of time charter rates on spot freight rates. Empirical studies indicate that there are two-way lead–lag relationships between the time charter and spot freight rates and that a time charter contract has a price discovery function. Smaller ship sizes and longer durations lead to a stronger price discovery function.     

氰化尾矿干堆技术应用实践

以浙江省遂昌金矿有限公司氰化尾矿干堆技术应用为对象,对氰化尾矿干堆过程中出现的一系列问题进行了深入分析,并采取有效措施,实现了氰化尾矿干堆存放,从根本上解决了含氰废水外排问题,取得了不可估量的社会效益;实践证明,在南方多雨环境下,氰化尾矿干堆存放是可行的。     

From coping to adaptation to economic and institutional change – Trajectories of change in land-use management and social organization in a Biosphere Reserve community,Mexico

Smallholder farming communities are increasingly affected by local impacts of international market dynamics, and (inter)governmental economic and nature conservation policies to which they respond through coping or adaptation. Although the attributes that underpin the capacity to adapt are widely agreed upon in literature, empirical evidence on how rural communities can develop adaptations are still scarce. Here, we provide such evidence based on a comprehensive driver-response reconstruction of a community in the buffer-zone of a Biosphere Reserve in Chiapas, Mexico. We found that coping (between 1990 and 2000) was gradually replaced by adaptations (1995–2010) based on: (i) diversification of land-use, (ii) improved social organization, (iii) improved communal decision-making, and (iv) more sustainable forms of land management. The diversification of local farming systems through inclusion of organic forest-based palm and coffee cultivation and the establishment of associated organizations, formed the basis of these changes. These adaptations were mainly supported by improved social, institutional and political capital. Communal forest resources, long-term support of an NGO and a highly motivated population, were essential circumstances that allowed these trajectories to develop. However, current unequal land and power distribution could undermine and debilitate adaptive capacity. Communities and supportive organizations need to be aware and capable to adjust continuously to prevent today's adaptation strategies from becoming tomorrow's coping responses.     

Smart farming and short food supply chains: Are they compatible?

The challenge of sustainability and the need to secure the production of high-quality, affordable and healthy food, have led to the emergence of alternative food production/distribution schemes that, based on technological or organizational innovation, can increase food production without burdening the environment. Both smart farming and short food supply chains (SFSCs) are considered as promising solutions towards this target. From a theoretical standpoint, the introduction of smart farming technologies into SFSCs could increase the value-generating capacity of short food supply schemes. However, a pivotal question is whether such technologies are compatible with SFSCs. In this study, following a mixed research design, we analyze Greek farmers’ and consumers’ perceptions of the compatibility between smart technologies and SFSCs, and we examine the extent to which compatibility perception affects willingness to engage in “smart SFSCs.” Quantitative results revealed that perceived (in)compatibility is central in predicting this willingness for both farmers and consumers. The qualitative strand of the study uncovered the existence of two different types of compatibility. Actual compatibility refers to the consistency of smart technologies with the technological advancement of farms and the real everyday needs of farmers. Symbolic compatibility relates to the meanings attributed to both SFSCs and smart technologies by farmers and consumers. In sum, the results indicated that smart technologies are viewed as tools that can lead to a conventionalization of SFSCs, thus altering their optimally distinct nature. Policies targeted at the promotion of smart farming should go beyond traditional views of smart technologies as tools that increase farm efficiency, by paying more attention to their compatibility with different “agricultures” and to the ways they can transform farming systems.     

振动压实试验方法在无机结合料配合比设计中的应用

无机结合料稳定材料振动压实试验方法适用于粗集料含量较大的稳定材料。本文结合连霍高速路面加宽工程介绍了水泥稳定基层配合比的振动压实试验设计方法及特点。     

Strategies for integrating farmers into modern vegetable supply chains in Vietnam: farmer attitudes and willingness to accept

In Vietnam, the development of so‐called ‘modern’ vegetable supply chains is receiving considerable interest amongst researchers and governments. This interest partly stems from the view that enhancements in food safety can be achieved if farmers are willing to adopt supply chains that are often associated with ‘western’ forms of retailing. Our study investigates farmers’ willingness to change to two ‘modern’ alternatives – a supply model based on cooperatives and another based on investors facilitating the change. Using discrete choice data drawn from 412 farmers, mixed logit models in willingness to pay space are developed that reveal the relative importance of different drivers of change. The paper offers insights that can inform governments about the incentives required to bring about change. In addition, the paper illustrates the novel application of a choice experiment to enumerating the perceived costs of changes in vegetable supply chains.     

Assessing the socio-economic dimensions of the rise of organic farming in the European Union

Organic farming is considered one of the most important rural development tools in the European Union, often connected to the socio-economic objectives of small-farm support and employment generation. Using an EU-27 regional panel data-set from 2000 to 2010, I show that the share of a region’s agricultural area under organic methods is positively associated with average farm size. Furthermore, I show that the share of organic farming in a region is not associated with higher application of agricultural labor per hectare. Both results question the connection between organic farming and the aforementioned objectives, and point to the conventionalization of European organic farming.