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121.
122.
The 'clean green image' of New Zealand is a well-known example of what has been called a 'place myth'. But more recently, emerging alongside this place myth is an image that the government is trying to co-create of New Zealand as an innovator in biotechnology. In nationwide focus groups, whilst a matter of pride, participants typically saw this clean green myth as a temporally distant utopia. However, when considered alongside the futures proposed by biotechnology, clean green New Zealand was mobilized into the present moment to defend a general reluctance to take up these practices. Alternately, some participants saw the possibility for co-evolution of the place myths, with biotechnology enabling the re-construction of a 'picture-perfect', clean green country. 相似文献
123.
The spatial and temporal patterns of pedogenesis on stabilized dunes at Shapotou, northwestern China, were studied on the time sequences of 0, 18, 35 and 43 years. The spatial pattern of soil formation was estimated by measuring the thickness of accumulated sand fractions on the stabilized dune surface and by analyzing the characteristics and properties of soil. The results showed that the environment of soil formation and circulation of soil material were influenced in the processes of shifting-sand fixation, and the mean soil particle size changed from >0.2 to <0.08 mm in 0–20 cm soil depth with the succession from cultivated plants to natural vegetation. The capacity of available soil water increased fivefold. Deep infiltration of water in soil no longer occurred due to the increase in soil water capacity and the change of redistribution of soil water in profiles. Soil microorganisms evolved from simple to complex. Interaction of these processes obviously brought about accumulation of soil fertility, evolution of soil profiles and development of the profiles towards aripsamments. The difference of micro-topography is closely related to redistribution of material and energy in soil formation. 相似文献
124.
校准平行光管的新方法及其原理 总被引:1,自引:0,他引:1
平行光管是光学实验及计量检测的重要设备。为获得平行光,平行光管的分划权必需严格位于物镜后焦面上。如何将分划权准确地调整至物镜后焦面?传统的诸多方法中,或因设备难求,或受环境制约而难尽人意。本文提出一种校准平行光管的新方法并论证其原理 相似文献
125.
FLUVIAL PROCESSES IN THE LOWER YELLOW RIVER AFTER LEVEE BREACHING AT TONGWAXIANG IN 1855 总被引:1,自引:0,他引:1
I. CHAncEL CHANGal m THE FLOODED AREA ArVER BREACHING AT TONGWAXIANG AND THEIR IMPACTSIn mid--June of 1855 a great flood occurred in the lower reaches of the Yellow River. The findmainly came down from the main stem of the river and itS tributary Qinhe River. In the meantimethe riparian area of the Yellow River had just been subjected to a heavy rain, and large amountS of water from mountains and hills were flowing into the river and lakes were also full. The Weis… 相似文献
126.
中国目前发现有43种自然疫源性疾病,其中鼠疫、人禽流感、疟疾、登革热等14种被列为国家法定传染病,对中国人民生命健康造成了很大的威胁。为了探讨中国自然疫源性疾病发病数量均衡/不均衡的区域分布规律,本文运用Shannon信息熵理论和空间自相关方法,基于2004-2015年14种自然疫源性疾病的发病数,对中国自然疫源性疾病进行了分析。研究结果表明:① 中国自然疫源性疾病发病数量均衡/不均衡的区域在空间上具有明显的西北-东南分异特征,并具有显著的空间自相关关系,高值聚集区和低值聚集区主要分布在以河北-云南连线上山脉分界线的两侧;② 自然因素是影响自然疫源性疾病发病均衡程度的主要因素,在温暖潮湿(即温度适宜、水分充足)的地区更容易发生多种疾病,疾病发病数量相近;在特定牲畜为主或特定蚊虫流行地区更容易发生单种疾病,疾病发病数量不均衡;③ 我国发病总数高的区域往往是因为单种疾病极其严重导致,而信息熵高的地区往往存在多种疾病发生,这两类地区在自然疫源性疾病防治上,需要根据地区特点采取不同措施。 相似文献
127.
The solubility of meat protein of croaker and jack mackerel was significantly affected by pH shifting. The protein yield of alkali-aided processing is higher than those of conventional and acid-aided processing. The addition of sarcoplasmic protein increases the breaking force and deformation value. The breaking force of recovered protein gel from alkali-aided processing is decreased by the addition of NaCI. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed that fish protein of alkali is similar to that at pH7.0. Alkali-aided processing for recovering fish protein is a valuable method for increasing the utilization of frozen and pelagic fishes and for making kamaboko products. 相似文献
128.
砂旋复花的防风固沙作用 总被引:4,自引:0,他引:4
砂旋复花是一种沙生先锋多年生草本植物,营养繁殖能力极强,能很好地适应恶劣的流沙环境。研究结果表明,砂旋复花群聚的防风固沙作用非常突出,作为一种优良固抄植物,值得在北方沙区大力推广。 相似文献
129.
Maize diversity is important to the livelihoods of millions of farmers in Mexico, the crop's centre of origin; to maize breeders seeking new genetic material; and to producers and consumers worldwide. Key social processes that determine maize diversity include historic and cultural emphases on maize as a primary crop; land-use practices encompassing heterogeneous agro-ecological conditions; farmers' seed-saving practices; farmer selection of useful traits; and farmer seed exchange and purchasing networks. We consider the impacts of recent agricultural and rural development policies on these processes. We focus on La Frailesca, a commercial and semi-subsistence maize-growing region in southern Mexico. Qualitative data were collected via focus group discussions, semi-structured interviews, and participant observation in four villages at intervals over a 2-year period. These techniques were complemented with semi-structured interviews with local and state policymakers. Observations suggest that policies promoting market liberalisation, agricultural modernisation, and rural education have contributed to significant changes in the social processes which have historically generated maize diversity. Increasing numbers of smallholder maize producers are diversifying into alternative livelihood options, including temporary or permanent migration, and cultural and economic emphases on maize production are changing. Changes in La Frailesca raise important questions about the fate of maize genetic diversity as the Mexican agricultural sector is further realigned with the global agricultural economy. 相似文献
130.
深源地震处理软件开发 总被引:1,自引:1,他引:0
为解决东北深震区的深震定位问题开发了相应软件,通过对东北地区以往深震处理的结果来看。效果较好。本文对该软件的开发和使用情况进行了介绍。 相似文献