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201.
Glutaraldehyde cross-linked gelatin was graft copolymerized with acrylic acid, acrylamide, vinyl acetate, methyl acrylate, and methyl methacrylate either individually or in combination. The enzymatic and fungal degradation of these graft copolymers with trypsin, pepsin, and mixed cultures ofAspergillus niger, Penicillium ochrochloron, Penicillium funiculosum, andTrichoderma viride was studied for short and extended periods. The weight loss suffered by the samples, the weight of biomass formed, the nitrogen content, and the pH of the culture medium were determined. With the help of these data, the extent of utilization of graft copolymers by fungi as a sole source of carbon was estimated. The samples with less than 100% grafting and with a ratio of polymethyl methacrylate content (L) to polyacrylic acid (H) content (L/H values) lower than 1.0 were readily and extensively degraded.IICT Communication No. 3375. 相似文献
202.
自然资源的非传统性开发是一个新的概念,包括非传统资源的开发和传统资源的非传统利用途径的开发两方面的内容。自然资源的非传统性开发的重大意义是:不断扩大自然资源开发的范围,向自然资源开发利用的广度和深度进军,促进地区经济建设的发展,充分发挥我国或一个省特有、珍稀自然资源的优势,增强竞争地位和能力;丰富自然科学的理论和技术,增加科学积累,促进国际学术交流。本文还着重讨论了自然资源非传统性开发的准备工作,非传统资源开发的实例和传统资源的非传统利用技术途径。 相似文献
203.
This paper proposes to test the ethical acceptability of four styles of agricultural resource management: (1) contemporary industrial integrated systems agriculture, (2) modern industrial input dependent agriculture, (3) continuous traditional agriculture and (4) non-continuous (or swidden) traditional agriculture. The test of ethical acceptability is whether or not these styles of agricultural resource management embrace or are even compatible with that pattern of practical reasoning and interaction among ethical agents which we have independent theoretic grounds for preferring. The preferred sorts of practical reasoning and interaction are those which we find operating in ethical theories which are strongly committed to letting the discretion of ethical agents construct what is right for them to do. Thus the discussion distinguishes several different strengths of constructivist ethics relating them to the work of John Rawls, Immanuel Kant and Onora O'Neill. Then it argues for the theoretic preferability of one particular strength of constructivist ethic. The paper winds up by arguing that only traditional continuous agriculture embodies the preferred sort of practical reasoning and interaction among ethical agents. Further, I argue that this is the only style of agriculture which can embody such reasoning and patterns of interaction. Thus, as we consider the role of agriculture in our plans of international development, we have one reason to try to favor traditional continuous agriculture. To do otherwise would ignore the ethical superiority of the practical reasoning and patterns of interaction of traditional agriculturalists. 相似文献
204.
Muhammad Akram Kahlown Joel R. Hamilton 《Journal of the American Water Resources Association》1994,30(1):125-134
ABSTRACT: The karez is a traditional irrigation water source, consisting of hand-dug horizontal wells, that is still used in parts of South Asia, the Middle East, and North Africa. This paper describes the construction, management, and current problems of karez irrigation systems based on investigations conducted in Baluchistan Province, Pakistan. While karezes have served irrigation needs well in the past, they are now threatened by high costs of labor for construction and maintenance, and by the encroachment of tubewells which lower the water tables on which the karez systems depend. Possible methods for improving karez performance and needs for research are discussed. 相似文献
205.
Asterios Tsioumanis Konstadinos Mattas Elsa Tsioumani 《Journal of Agricultural and Environmental Ethics》2003,16(6):605-616
Unauthorized appropriation of geneticresources has been described by the term``biopiracy.' Technological breakthroughsincluding biotechnological applications canincrease considerably the instrumental value ofbiodiversity as new products or products withnew properties can be made. Nevertheless, itappears that, in most cases, the properties inquestion were already known to the indigenouspeople and used for centuries. The analysisdiscusses both from an economic and an ethicalperspective whether it is just that traditionalknowledge is rewarded. As the conflictintensifies over questions of ownership andcontrol of biological materials, IntellectualProperty Rights are at the center ofcontroversies. The current global systemgoverning biotechnology has largely been shapedby Western expectations and valuations andconsequently has drawn severe criticism. Thecritics doubt both the stability andsustainability of the current patent system andargue for restructuring through benefit-sharingsystems in order to address some of theexisting inequalities. With the help of a casestudy (US patent no. 5,751 on ayahuasca) thetheoretical notion of biopiracy is applied toreal problems. 相似文献
206.
Vikram S. Negi Ravi Pathak K. Chandra Sekar R.S. Rawal I.D. Bhatt S.K. Nandi 《Journal of Environmental Planning and Management》2018,61(10):1722-1743
Ethnobotanical knowledge plays a significant role in plant diversity conservation and the curing of various ailments in remote rural areas of the Indian Himalayan Region (IHR). A total of 53 plant species from 27 families have been documented from the Byans valley and are used traditionally for the treatment of various diseases. Valley inhabitants have maintained a symbiotic relationship between natural resources and their cultural belief system by developing sacred forests/groves which conserve the region's plant diversity pool. Information on sacred natural sites and traditional beliefs was documented in order to understand the environmental and conservationist implications of these rules and practices. The study provides comprehensive information about eroding traditional knowledge and biodiversity conservation practices. This study could be a pilot to strengthen the conservation practices and sustainable utilization of frequently used bioresources by understanding the traditional knowledge system and conservation ethics of tribal communities in the Himalayan region. 相似文献
207.
Though still relatively new, the development of marine spatial planning has been based on the on the premise that as a rational planning process, it can be applied following universal principles and steps informed by land-based inspired theoretical underpinnings. However, within this process, differences between marine and terrestrial environments are being overlooked, potentially affecting the way in which the marine environment is understood and valued, and the development of a culture of practice for, and specific to, marine spatial planning. By framing planning as a cultural construct, this paper aims to explore the extent to which land-based rationales are affecting the development of a marine spatial planning culture of practice, with its own ethos and shared values. A culturalised planning model adapted from [Knieling, J. and Othengrafen, F. (2015). Planning culture—a concept to explain the evolution of planning policies and processes in Europe? European Planning Studies, 23(11), 2133–2147] is used as a framework. Whilst acknowledging the importance of the contributions from land-based planning and the ecological sciences, the findings suggest that those unconscious beliefs and perceptions affecting society’s understanding of the marine environment should contribute to informing shared values for marine spatial planning practice. 相似文献
208.
209.
Despite a highly visible presence, policy-maker knowledge of the drivers and participants in the informal economy of wild-harvested medicinal plants in Cape Town remains limited. To illuminate the workings of this local cultural business activity, the researchers adopted value chain analysis (VCA) for dissecting harvesting, trading and consumer demand in the trade. The study included qualitative, open-ended interviews with 58 traditional healers and a quantitative consumer study of 235 township households. Cape Town's traditional healers are numerous and potentially more uniquely culturally diverse than elsewhere, serving various community health needs. Healer groups enhance their healing reputation by utilising wild-sourced medicines – much of which is harvested locally. Their services remain culturally important and utilised by at least 50% of all consumer respondents. The VCA revealed a universal healer and consumer requirement for wild medicine stocks which has considerable implications for policy-making, protected area management and traditional medicine-oriented conservation projects. 相似文献
210.
BI Xiao-yi WANG Peng JIANG Hong XU Huan-yan SHI Shu-jie HUANG Jun-li 《环境科学学报(英文版)》2007,19(12):1510-1515
The catalyst of CuOx/Al2O3 was prepared by the dipping-sedimentation method using γ-Al2O3 as a carrier. CuO and Cu2O were loaded on the surface of γ-Al2O3, characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). In the presence of CuOx/Al2O3, the microwave-induced chlorine dioxide (ClO2) catalytic oxidation process was conducted for the treatment of synthetic wastewater containing 100 mg/L phenol. The relationships between removal percentage and initial ClO2 concentration, catalyst dosage, microwave power, contact time, initial phenol concentration and pH were investigated and the results showed that microwave-induced ClO2-CuOx/Al2O3 process could effectively degrade contaminants in a short reaction time with a low oxidant dosage, extensive pH range. Under a given condition (ClO2 concentration 80 mg/L, microwave power 50 W, contact time 5 min, catalyst dosage 50 g/L, pH 9), phenol removal percentage approached 92.24%, corresponding to 79.13% of CODCr removal. The removal of phenol by microwave-induced ClO2-CuOx/Al2O3 catalytic oxidation process was a complicated non-homogeneous solid/water reaction, which fitted pseudo-first-order by kinetics. Compared with traditional ClO2 oxidation, ClO2 catalytic oxidation and microwave-induced ClO2 oxidation, microwave-induced ClO2 catalytic oxidation system could significantly enhance the degradation efficiency. It provides an effective technology for the removal of phenol wastewater. 相似文献