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1.
走进建材城,各式各样的龙头让人眼花缭乱,款式有手按的、提拉的、旋转的、脚踏的、混水的、自动感应的很多种,适用地点还各不相同,价格也参差不齐,要想从中选购一款合适自己的产品还真不容易,所以请看以下选购龙头的小指南,希望能给你一些帮助。  相似文献   

2.
白皙美丽的肌肤是所有女性梦寐已求的,只有保养好内层肌肤,表面的肌肤才能健康美丽。健康的内层肌肤对美化表面肌肤至关重要。随着冬季的来临,由于温度和湿度的变化,皮肤新陈代谢的速度减慢,使皮肤保留水份的能力降低,因此皮肤变得很干。而新陈代谢减慢,又会导致受伤的皮肤细  相似文献   

3.
爱的那朵云     
一、遗失的手套段小苏:初春的午后,我将满满两抽屉的手套整理出来,洗净,晾晒,那一排排粉红、浅蓝、鹅黄、草绿、雪白的手套吸引了对面楼里那个扎着好多辫子的小女孩,她趴在阳台上,用兴奋的语调问我:姐姐,你的那些漂亮手套为什么只有一只呢,它们的另一半呢?它们的另一半被我落在了夏宇的口袋里。以前,每次让他把手套还给我的时候,  相似文献   

4.
《绿色中国(A版)》2010,(9):56-61
总政歌舞团著名青年歌唱演员、国家一级演员蔡国庆获奖感言:这样的时刻在我心中是充满真情和温暖的,因为我始终坚信绿色的中国才是一个更加和谐美丽的中国。我愿意作军中的一棵小白杨,我希望用我的爱心和歌声守护祖国每一片绿色的森林和我们心中绿色的家园。  相似文献   

5.
十月赞歌     
总是在初秋的时候,就充满了对十月的憧憬;总是在金秋的季节,就充满了对十月的渴望。穿过季节的群山,我们以热烈的心跳去拥抱十月旭日的第一缕曙光。越过岁月的河流,我们的心境犹如十月天空第一片柔美耀眼的云裳。  相似文献   

6.
08香水风尚     
香水,这种神奇的化妆品,能带给女人自信和欣喜,它可以愉悦你的心情、平衡你的情绪、表达你的心意、体现你的气质、协调你与周围环境的关系。难怪有人说,一个真正懂得美的女人一定是一个选择和使用香水的高手。的确,香水是造就一个女人整体美的必备单品。本季,各大香水品牌又纷纷推出新品,给爱美的女人更多选择的机会。雅诗兰黛Sensuous系列  相似文献   

7.
云平 《云南林业》2011,(1):21-21
绵延的绿海,茂密的树林,潺潺的溪水,是刚刚离开这个世界的杨善洲留下的最直观的宝贵财富。同时,他还留给我们更多的宝藏。这些宝藏中最重要的,是他为党和人民的事业奋斗终生的精神。从领导的位子上退下来后,  相似文献   

8.
五月槐花香     
喜欢五月的味道,因为五月的阳光下流光溢彩着各色的神奇,空气中也都逸动着各色花蕊的甜香气息。喜欢五月的满眼新绿,因为生物都舒展开自身的躯体,展现出了生命的蓬勃生机,并把生命的活力化为最为眩目灿烂的美丽。五月里,无论是多么柔弱的生命,都会毫不掩饰自身的美质,都会涂抹装点着春光明丽的斑斓和尽情渲染着绿色的柔情欣喜。  相似文献   

9.
人与自然的和谐相处,是生态文明中的重中之重。建设生态文明不是一代人的事情,而是要人类世代相传。那么,在我们的下一代人心目中是如何看待人和自然的关系呢?我们在这里选发了三篇小学生的文章,让读者从中去感受稚嫩心灵对自然界的认识,这是人与自然和谐相处的根基,也是人类未来的希望所在。  相似文献   

10.
小巷的记忆     
在记忆里,家乡的小巷充满着平凡的快乐,给我的童年留下滚烫的记忆。家乡的小巷很窄,小巷两边挤满住户,屋檐相接,错落有致,挤出了中间一条弯弯曲曲的小路,延伸着我的记忆。家乡的小巷很长,铺一路的碎石或石板,那里有我童年时代的嬉笑,有我少年时代的初恋,有我离别时的留恋。  相似文献   

11.
Abstract

Three popular terms-leadership, sustainable and development-are examined. The paper argues that these three terms must be separated rather than combined if they are to aid our understanding and management of human and natural resources to meet challenges of an increasing human population with rising expectations for ever rising material gains. The contrasting theories and practices of Chairman Mao and Taoism ‘test’ these ideas and suggest the sideboards of alternatives in applying the three concepts to social ecological challenges of the 21st century. A modern theory of diffusion of innovation suggests how leaders might establish a ‘sustainability science’ whose findings could encourage the acceptance by humanity of a covenant of constraint on material consumption in conjunction with an ark of technical opportunity for more effective and efficient systems of material management.  相似文献   

12.
家具行业的发展为行业标准化提供了现实条件,家具企业标准化体系的建立是家具行业标准化工作的基础。家具企业标准化体系包括家具产品标准化、家具生产工艺技术标准化和家具企业管理标准化三个重要组成部分。笔者论述了家具食业标准化体系建设工作的原则、目的、具体内容和方法。  相似文献   

13.
A major problem for small farmers in the semi-arid tropics is the chronic shortage of fodder for draft animals. Leucaena leucocephala has improved productivity in many places in India and in various cropping systems, usually as either a pure crop or in a hedgerow alley-cropping configuration. Mixed cropping with arboreal forms is seldom seen. For off-season fodder production, hedgerows have the disadvantage of being open to unmanaged browsing when unfenced (as is usual). Arboreal forms are generally far less vulnerable. In this paper, the components of production of sorghum and arboreal Leucaena are measured under different intensities of canopy lopping. The most productive management system of those examined was pollarding of the Leucaena at the time of under-sowing with sorghum. In a year with less than 50% of average seasonal rainfall, this system gave a yield of 4.6 tonnes/ha/yr fresh wt fodder and 3.8 tonnes/ha/yr dry wt. of fuel harvests, while increasing the standing crop of wood by 1.8 t/ha/yr and retaining a yield of sorghum grain equivalent to 46% of pure sorghum cropping; the LER of this system was 1.35. Cash values of the alternative management systems were estimated, including the discounted Net Present Value of the standing crop of timber. Maximum value was attained with unlopped pure crop Leucaena followed by pollarded Leucaena with sorghum; pure crop sorghum achieved a lower value. These results demonstrate both the high productivity of Leucaena/sorghum based systems, and the stability of production even in poor rainfall conditions. Pollarding transferred the high future value of Leucaena timber to the present value of sorghum grain and fuelwood.  相似文献   

14.
In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.  相似文献   

15.
瓜州绿洲植被退化原因及保护对策   总被引:1,自引:0,他引:1  
瓜洲县近年来人口数量增长和土地开发规模过大,成为水资源紧张、植被退化、生态环境质量下降的重要原因之一,对绿洲农业生产和人居环境影响很大,因此,严格控制人口数量的增长和土地开发规模,大力发展节水农业,保障生态供水,加强对现有植被的保护,维护生态平衡,是瓜洲县实现可持续发展必须认真考虑的问题。  相似文献   

16.
The olive psyllid, Euphyllura phillyreae Foerster is one of the most destructive pests on buds and flowers of olive tree (Olea europaea L.) in May when the olive growers cannot apply any insecticides against the pest. Temperature-dependent development of the psyllid was studied at constant temperatures ranged 16–26°C. A degree-day (DD) model was developed to predict the larval emergence using the weekly cumulative larval counts and daily mean temperatures. Linear regression analysis estimated a lower developmental threshold of 4.1 and 4.3°C and a thermal constant of 164.17 and 466.13 DD for development of egg and larva, respectively. The cumulative larval counts of E. phillyreae approximated by probit transformation were plotted against time, expressed as the sum of DD above 4.3°C, the starting date when the olive tree phenology was the period of flower cluster initiation. A linear model was used to describe the relationship of DDs and probit values of larval emergence patterns of E. phillyreae and predicted that 10, 50 and 95% emergence of the larvae required 235.81, 360.22 and 519.93 DD, respectively, with errors of 1–3 days compared to observed values. Based on biofix depends the development of olive tree phenology; the DD model can be used as a forecasting method for proper timing of insecticide applications against E. phillyreae larvae in olive groves.  相似文献   

17.
在当前碳达峰、碳中和的目标下,开发制备高附加值的半纤维素化学品具有广阔的应用前景,而且对人类社会可持续发展具有重要意义。但半纤维素由于其复杂和不均一的结构致使研究和利用受到限制,存在着易降解、收率低、纯化困难、成本高等问题。因此,如何提高木质纤维原料中半纤维素及其解聚产物的提取率成为研究的热点与重点。文章对近年来提取半纤维素及其解聚产物的研究进行了综述,简述了提取半纤维素的不同预处理方法,并分析了一定的降解方法得到半纤维素的解聚产物——木寡糖和木糖;在此基础上,为研究竹材半纤维素提取技术与工业应用提出了建议;最后,结合发展趋势,特别是针对竹材应用领域,指出了未来半纤维素及其解聚产物的发展方向。  相似文献   

18.
我国湿地概况与发展趋势   总被引:2,自引:0,他引:2  
湿地是内部过程长期为水所控制的水-陆过渡的复合生态系统。综述我国湿地资源的概况,指出我国湿地资源丰富、生物多样性较高,但存在较为严重的湿地退化现象。从湿地功能和效益开发、湿地保护区建设、湿地恢复与重建三方面总结了国内湿地研究的重点,并对未来湿地研究的发展趋势进行了展望。  相似文献   

19.
Arid lands in the Mediterranean Basin harbour populations of saltbushes over substantial areas. These have been grazed for centuries and often cleared. There are also some 100,000 hectares of artificially established saltbushes, both native and exotic; they include no more than half a dozen species, when large scale plantations are concerned. Another dozen of exotic species, introduced from Australia, Southern and Northern America, have successfully undergone field trials and could be used on a large scale in a near future. The present paper attempts to review the current state of knowledge on Atriplex spp. in the Mediterranean Basin as a means of Arid Land rehabilitation at a time where huge areas in the region have undergone processes of severe degradation or have been subjected to desertization, particularly over the past four decades. In spite of a number of constraints in their establishment, management and utilization, the plantation of Atriplex spp. appears as one of the best way, if not the best one, to rehabilitate desertized areas and restore them to production, under the present state of knowledge on arid land rehabilitation. They, in particular, are amenable to inclusion into new, man-made agro-sylvo-pastoral systems of production well adapted to arid lands and to the needs of their populations.  相似文献   

20.
广元是我国少有的油橄榄适生区之一,具有较大的油橄榄产业发展潜力。文章介绍了广元市油橄榄发展现状,分析了存在的问题,提出了相应的发展对策。  相似文献   

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