美白防晒我与阳光玩游戏

夏日的阳光直接、浓烈,让人无处可躲,怕晒黑的姐妹们四处搜集新鲜出炉的防晒信息,为接下来一整夏的防晒做充分地准备.然而,要真正做到防晒,首先要了解紫外线是如何伤害皮肤的.     

夏天防晒要会吃

夏天防晒，人们往往会想到各种各样的护肤品，防晒霜。防晒不仅要做表面文章，内在的补养也很重要。这里介绍4种具有防晒功效的食物，不妨试着多吃一些。     

夏日防晒美白完全手册

A:防晒化妆品种类有几种 越来越多的人们开始使用防晒制品，以防止紫外线辐射对人体的伤害。业内人士提示，消费者不仅要考虑紫外线的急性严重日晒红斑和晒伤，而且要考虑较弱、慢性、反复和积累性日晒及其他污染等对皮肤的损害。多数研究证实，将uvA和uvB防晒剂复配后的防晒产品可明显提高对紫外线     

夏日防晒ABC

近期随着气温的不断攀升,人们也开始采取各种方式来抵御阳光的侵害。如何正确使用各种防晒产品以避免不必要的伤害,下面就让我们一起探究一番:A.遮阳伞有的市民认为伞面的颜色越深防晒效果越好,这种观念是错误的,防不防晒主要看面料。地摊上也有很多色胶面料的遮阳伞,比较劣质的遮阳伞摸起来手感粗糙,用久了在伞的折痕处会掉色,打开     

防晒、防冻护肤霜

目前,市售的护肤霜剂只具有防晒或防冻的功效,远远不能满足高寒山区紫外线辐射强度大,寒冷时间长的气候要求。在此,我们经反复试验研制,现提供一种既防晒(特别是紫外线辐射灼伤),又防冻伤的     

东莞“可园”热环境设计特色

东莞“可园”在防晒、通风等设计方面有其特独手法，从而在盛夏创造了良好的热环境。     

沙棘油中的紫外线吸收成分及防晒霜

对沙棘种子油,果渣油、果汁油中吸收中波段,长波段紫外线的活性成分作了介绍和比较,并就其相应的防晒机理,护肤作用及防晒霜的实例论述。     

QuEChERS柱-高效液相色谱/三重四极杆质谱联用法测定防晒喷雾中胡莫柳酯的不确定度评定

使用高效液相色谱/三重四极杆质谱联用法对防晒喷雾中胡莫柳酯进行不确定度评定,分析测量过程中不确定度的来源,并对各个不确定度进行合成。结果表明：曲线拟合引入的不确定度分量是标准不确定度的主要来源,防晒喷雾中胡莫柳酯的含量为4.94 mg/kg时,扩展不确定度为0.698 mg/kg。     

辣木油对小鼠抗紫外线损伤的保护作用

研究辣木油对小鼠抗紫外线损伤的保护作用,为开发防晒护肤品提供实验依据。采用中波(UVB 290~320 nm)和长波(UVA 320~400 nm)紫外线照射小鼠背部皮肤及双耳,造成小鼠皮肤及双耳灼伤水肿模型,以皮指数、耳指数、表皮厚度及皮肤组织病理学等指标评价辣木油对该模型的保护作用。结果显示辣木油组小鼠的耳指数、皮指数、表皮厚度均低于模型组且有显著性差异,能明显抑制紫外线射伤所致小鼠皮肤表皮角质化与浸润,抑制真皮层组织病理改变,提示了辣木油具有抗紫外线损伤的功能即防晒功能。     

五味子的整形

正五味子枝蔓柔软不能直立,需依附支持物缠绕向上生长。因此,它的整形工作包括设置支持物和修剪两项任务。(1)设置支持物。五味子在定植的当年生长量大小存在较大差异,在苗木质量差、管理不良的条件下,株高一般只能达到50～60cm,但经平茬修剪,第二年平均生长高度可达150cm以上,第三年可布满架面。所以一般可在第二年春季(5月上、中旬)设置支持物。支持物可采用架杆和防晒聚乙烯绳,架杆常选用竹竿,竹竿长,上头直径;防晒聚乙烯绳采     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

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.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.