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1.
研究检测酸乳塑杯封口盖膜揭开力的测试方法,利用专门的力值检测设备完全模拟人机操作对酸乳塑杯盖膜揭开力进行量化,主要表征为初始揭开力和持续揭开力.并以聚丙烯(polypropylene,PP)和聚苯乙烯(polystyrene,PS)2种塑杯,铝箔复合膜、镀铝复合膜、压花铝片3种封口盖膜组合的市售酸乳包装为实验对象,通过该测试方法进行塑杯包装封口盖膜揭开力测试,最终得到不同包装形式相应的盖膜揭开力力值范围.结果表明:塑杯封口盖膜的初始揭开力明显大于持续揭开力,PS、PP塑杯封口盖膜初始揭开力值为10~25 N;以压花铝片为封口材料时,塑杯封口盖膜的持续揭开力大于10N,以铝塑复合膜为封口材料时,塑杯封口膜的持续揭开力仅为4~8N;同种封口盖膜,PS塑杯的盖膜揭开力大于PP塑杯.而同种塑杯,镀铝封口膜的初始揭开力高于压花铝片和铝箔封口膜,压花铝片的持续揭开力高于镀铝封口膜和铝箔封口膜,差距悬殊.且以压花铝片为封杯材料时,盖膜初始揭开力与持续揭开力的差值会明显小,封杯强度相对稳定.  相似文献   

2.
所谓塑棚养鸡就是利用塑料大棚来饲养肉鸡.此种养鸡方式由于鸡舍投资省,建造时间短,见效快,所以近年来各地塑棚养鸡发展较快.但由于塑棚内特殊的环境条件,使鸡易患多种病症,在一定程度上制约着塑棚养鸡生产的发展和推广.为了在农村进一步搞好这项技术的推广应用,现将塑料棚养鸡几种常见易患病的防制措施介绍如下.  相似文献   

3.
营双高速K345+250-K346+100段为软流塑-软塑状态黄土状粉土与盐渍土结合的工程案例,两种病害同时出现,将可能引起高速公路路基性质的复杂化,特别是在有充沛含盐水源供给条件下,盐渍土软基对公路路基的病害更为严重,本项目在参考类似工程处置措施基础上,充分考虑本项目硫酸盐渍软土地下水位高、呈流塑塑状态、土颗粒粒径小、级配不良且具中软塑状态、土颗粒粒径小、级配不良且具中腐蚀性等特点,提出常用处理措施。  相似文献   

4.
塑膜暖棚养猪,简称塑棚养猪。即在冬天,将塑膜覆盖在猪圈的门、窗和运动场上空,在春夏秋季再换遮纱网的封闭式养猪法,称之为塑棚养猪。1塑棚养猪的重要性1995年,江苏省沐阳县生猪饲养量154-9万头,出栏856万头,出栏率只有139%。多年来,我县肥猪出栏率一直徘徊在110%~139%之间。究其根本原因,主要是广大群众传统的养猪办法没有改变。而塑棚养猪,可以做到夏降温,冬保暖,使猪一年四季正常生长,出栏率高。1994年,我县高墟、悦来、马厂、苏圩等乡镇重点推广塑棚快速养猪法,到1994年底,全县已有10个乡镇,1300户采用塑棚养猪…  相似文献   

5.
一、推荐组合方案Ⅰ—适宜中小型企业近距离配送的包装方案从评分表看出PP、PS塑杯与八连杯的评分最高,市场上这两种包装主要用于酸奶及活性乳饮料包装,而极少用于包装鲜牛奶,主要是由于很多塑杯生产厂由于设备条件限制无法保证塑杯的卫生标准,而影响保质期。近来有些厂家采用灌装前对包材进行简单杀菌处理,同时在鲜奶中加入细菌抑制剂的办法,可使鲜奶保质期达到7天,而近来国内几家主要的塑杯生产厂如上海格莱纳、湖南万容等到均已引进世界先进的自动化塑杯生产线,使其塑杯的卫生品质与外观质量均已得到大大提高,为杯装鲜奶创造…  相似文献   

6.
“在炕头上搞塑编加工,既不累又不耽误家里活,一个冬天下来,可增加收入2000多元”,山东省蒙阴县常路镇大常路村农家妇女王艳边编筐边笑着说。自去冬以来,这个镇积极引导农家妇女利用冬闲有利时机,搞起了简单易学,原料成本低的塑编技术制作工艺,  相似文献   

7.
经过20多年的努力,大丰重引入麋鹿历经完全人工饲养、半人工散养及放归自然的风土再驯化和行为再塑过程,已初步建立了野生种群.野外观察为建立麇鹿种群奠定了坚实基础,这不仅是麋鹿重引入成功的基础性工作,而且是重中之重的工作.切实开展好麋鹿野外观察工作,必须明确观察目的,了解观察方法,熟悉观察内容,注意观察事项,这不仅能提升保护区专业技术人员能力,而且可以为进一步做好科学研究、实施麋鹿种群的有效管理提供可靠依据.  相似文献   

8.
春蚕塑料大棚育   总被引:1,自引:0,他引:1  
1980年春期,我们在平阳县联华大队进行了稚蚕室外塑棚,大蚕地坑育的试验。实践结果,18张春蚕种平均张产94斤。平均每张蚕种加温木炭不到4斤,即加温成本不到4角。比去年张产提高24斤,加温木炭从20斤降到4斤。兹将塑棚构造情况简述如下: 塑棚的构造采用拱形软体结构,用毛竹、塑料薄膜、草帘等材料。棚顶高2.6米,边高1.8米,宽3.1米,长6米。棚内两边搭蚕架,中间作业道。棚外四周开排水沟,占地约28平方米。  相似文献   

9.
美国马里兰大学的畜牧学家通过研究断奶前仔猪采食行为的发育,明确了何时及如何开始补料。R.A.Barczewski和T.G.Hartsock从研究中发现,促使仔猪提早采食补料,可增加补料的总摄入量。试验母猪从妊娠109天起饲于镀塑金属地面的抬高的分娩栏中,每天早晨8时喂一次含14%粗蛋白的强化玉米-大豆饼粉饲粮1.8千克。分娩后喂给同种饲粮,但保证饲槽中始终装有饲料以供随意采食。  相似文献   

10.
<正> 近几年来,我们将塑膜农业引向了村镇庭院经济,重点对冬季庭院塑棚养鸡方面进行了试验、推广,摸索了一些经验,现介绍如下。 冬季塑棚养鸡设备简单,投资很少,技术简易,受益快,是农民寇院经济致富的项目,也是村镇广大养鸡户全年能否取得高效益的关键性一着。鸡棚可大可小,小的可养10来只、几十只,大则可上千只。  相似文献   

11.
由于气温的变化,原来属于夏季繁殖鸟的国家一级保护鸟类黑鹳(Ciconia nigra),在北京市出现了越冬群体.为了解黑鹳的越冬生态特点,从2004年1月到2009年3月,在北京十渡水生动物自然保护区,对其种群数量、生境选择、取食规律和集群行为进行了实地调查.结果显示,黑鹳选择该保护区的拒马河作为其越冬地,种群数量从2004-2005年冬季的28只下降到2007-2008年的17只,但随后恢复到了23只.越冬群体于11月中旬形成,次年3月中旬分散,但群体形成受到温度变化的影响.黑鹳对取食生境具有依赖性,主要食物为鱼类(>92.4%).成年和亚成年黑鹳的食物构成没有差异(Mann-Whitney Utest,U=1.00,p=0.44).在越冬初期,取食活动主要发生在早晨和中午,越冬中期则集中于下午,而在越冬后期,分为清晨和傍晚两个取食阶段.按照每日取食6 h计算,成年黑鹳的每日进食量约538 g,亚成年个体约449 g,与人工饲养条件下黑鹳的饲喂量相近.在越冬后期,观察到取食过程中群体内部存在争斗行为.对越冬黑鹳的干扰主要来自旅游活动对取食生境的改变、人为筑坝提高水位、在滩涂开辟新的旅游场地减少了适于黑鹳取食的空间.  相似文献   

12.
以内蒙古民族大学草业科学2002级、2003级学生为教学改革对象,对牧草育种学课程的教学大纲、考核评分体系进行修订,并采用模糊数学隶属函数法对草业科学专业4个年级的课程论文、毕业论文、实践教学成绩及考研录取率进行综合评价,以此反映牧草育种学课程改革的效果.结果显示:4个年级组的隶属函数总平均值排序为:2002级(0.844 6)>2003级(0.519 1)>2001级(0.410 5)>2000级(0.047 10).说明改革后(2002级、2003级)学生专业素质与水平有一定提高.  相似文献   

13.
A growing number of studies have looked at how climate change alters the effects of habitat fragmentation and degradation on both single and multiple species; some raise concern that biodiversity loss and its effects will be exacerbated. The published literature on spatial dynamics (such as dispersal and metapopulation dynamics), habitat fragmentation and climate change requires synthesis and a conceptual framework to simplify thinking. We propose a framework that integrates how climate change affects spatial population dynamics and the effects of habitat fragmentation in terms of: (i) habitat quality, quantity and distribution; (ii) habitat connectivity; and (iii) the dynamics of habitat itself. We use the framework to categorize existing autecological studies and investigate how each is affected by anthropogenic climate change. It is clear that a changing climate produces changes in the geographic distribution of climatic conditions, and the amount and quality of habitat. The most thorough published studies show how such changes impact metapopulation persistence, source–sink dynamics, changes in species' geographic range and community composition. Climate‐related changes in movement behavior and quantity, quality and distribution of habitat have also produced empirical changes in habitat connectivity for some species. An underexplored area is how habitat dynamics that are driven by climatic processes will affect species that live in dynamic habitats. We end our discussion by suggesting ways to improve current attempts to integrate climate change, spatial population dynamics and habitat fragmentation effects, and suggest distinct areas of study that might provide opportunities for more fully integrative work  相似文献   

14.
Many grazing-management challenges stem from poor livestock distribution resulting in overuse of some areas and low utilization of others. Managing livestock-distribution patterns requires knowledge of pasture characteristics and animal behavior patterns. Behavioral patterns result from recognizable processes that include inherited attributes, individual and social learning systems, cue-consequence specificity, predispositions toward novel stimuli, and spatial memory. Through these behavioral mechanisms, animals form and revise preferences and aversions for specific locations in their foraging landscape. To accomplish habitat selection, domestic herbivores use sight and sound cues to seek and return to high-quality foraging locations. Nested within habitat selection are learned diet preferences and aversions by which ungulate herbivores associate taste with positive or negative postingestive feedback. The deliberate and careful modification of animal attributes and habitat characteristics could yield options for adaptive rangeland management. In this article, we describe the basic principles that underlie how animals make decisions about where to forage and how long to stay in a particular habitat. We also suggest management practices designed to modify animal behavior and alter habitat-use patterns.  相似文献   

15.
Habitats are characterized by different local environmental conditions that influence both behavior and morphology of species, which can result in habitat-dependent phenotypic differences among animals living in heterogeneous environments. We studied 3 alpine populations of Eurasian red squirrels (Sciurus vulgaris), 1 living in a marginal high-elevation habitat at the edge of the species’ altitudinal distribution, and 2 occurring in higher-quality habitats. Here, we investigated whether squirrels living in the marginal area differed in 2 morphological parameters (body size and body mass) and/or in the expression of 4 personality traits estimated with an open field test and a mirror image stimulation test (activity, exploration, activity-exploration, and social tendency). Furthermore, we tested whether within-individual variance of the traits (behavioral plasticity) was higher in the edge habitat. Male squirrels in the edge habitat were smaller and weighed less than in the other study areas, while among females, size–habitat relationships were less marked. These sex-specific patterns were explained by a strong association between body mass and reproductive success in female squirrels. Squirrels in the marginal habitat were more active, explorative, and had a more social personality than in the other habitats. However, in contrast to our predictions, behavioral plasticity was smaller in the marginal habitat, but only for the trait exploration. Our results suggest that animals choose the habitat that best fits their personality, and that habitat-related differences in selective pressures may shape animals’ morphology.  相似文献   

16.
Rodent pests severely damage agricultural crops. Outbreak risk models of rodent pests often do not include sufficient information regarding geographic variation. Habitat plays an important role in rodent–pest outbreak risk, and more information about the relationship between habitat and crop protection is urgently needed. The goal of the present study was to provide an outbreak risk map for the Dongting Lake region and to understand the relationship between rodent–pest outbreak variation and habitat distribution. The main rodent pests in the Dongting Lake region are Yangtze voles (Microtus fortis). These pests cause massive damage in outbreak years, most notably in 2007. Habitat evaluation and ecological details were obtained by analyzing the correlation between habitat suitability and outbreak risk, as indicated by population density and historical events. For the source‐sink population, 96.18% of Yangtze vole disaster regions were covered by a 10‐km buffer zone of suitable habitat in 2007. Historical outbreak frequency and peak population density were significantly correlated with the proportion of land covered by suitable habitat (r = 0.68, P = 0.04 and r = 0.76, P = 0.03, respectively). The Yangtze vole population tends to migrate approximately 10 km in outbreak years. Here, we propose a practical method for habitat evaluation that can be used to create integrated pest management plans for rodent pests when combined with basic information on the biology, ecology and behavior of the target species.  相似文献   

17.
桑天牛长尾啮小蜂对桑枝挥发物的触角电位和嗅觉反应   总被引:2,自引:0,他引:2  
桑天牛长尾啮小蜂(Aprostocetus fukutai)是蛀干害虫桑天牛(Apriona germari)的重要卵寄生蜂之一,桑天牛危害的桑枝挥发物在该寄生蜂寄主生境定向搜寻过程中起着至关重要的作用。采用触角电位(EAG)仪测定了桑天牛长尾啮小蜂对8种桑枝挥发物的电生理反应,发现该寄生蜂对这8种桑枝挥发物都能产生电生理反应,且随着化合物浓度的增加电生理反应增强。利用Y型嗅觉测定仪测定了桑天牛长尾啮小蜂对不同浓度挥发物的趋性行为,结果显示0.01%月桂烯、0.01%里那醇和1%Z-乙酸-3-己烯酯对该寄生蜂均具有显著的引诱作用。研究结果对揭示桑天牛长尾啮小蜂寄主定向的化学本质具有重要意义。  相似文献   

18.
The cao vit gibbon is a critically endangered species. Only approximately 110 individuals remain in degraded karst forest along the China‐Vietnam border. Karst forest is unusual gibbon habitat. Currently, the canopy height of cao vit gibbon habitat is approximately 10 m. Research on the locomotor behavior of gibbons living in this particular forest type might provide important insight into locomotor stability and variability of gibbons. We used 5 min scan samples to record the locomotion mode, support use and canopy strata of gibbons in 3 groups for 2096 h between January 2008 and December 2009. Although cao vit gibbon habitat has a lower canopy in comparison to that of other forests inhabited by gibbons, cao vit gibbons displayed a similar overall locomotor pattern to other gibbon species (Symphalangus syndactylus, Hylobates lar and Hylobates agilis) in which brachiation dominate their locomotor behavior. Cao vit gibbons spent most of their time travelling on inclined branches (2–10 cm) in the middle stratum through the forest canopy. Adult females appear to more often employ safer modes of locomotion (bridging more often and brachiation less), while adult males choose riskier modes (leaping more and climbing less). As gibbons increased in body weight, as they grew from infant to adult, they tended to use larger supports. This research documented that locomotor behavior in Hylobatidae is strongly determined by anatomical characters, but cao vit gibbons also show the ability to use various supports, enabling them to survive in karst forest.  相似文献   

19.
将高原鼠兔的日常行为划分为采食、警戒、嬉戏和洞内滞留4个类型,选取植被高度、盖度和地上生物量3个代表性指标反映草地植被性状的变化,探讨了植被性状与高原鼠兔(Ochotona curzoniae)行为模式的对应关系。结果表明,植被高度、盖度和生物量的增加可导致高原鼠兔洞内滞留和警戒时间增加,采食和嬉戏时间减少;高原鼠兔的某些行为对植被性状各主要指标变化应对反映有一个由量变到质变的临界点或临界范围,在此临界点或临界范围之前和之后,高原鼠兔对植被环境的感受会发生质的改变;采食时间与洞内滞留时间的比值(G/H)越小,表明植被环境的胁迫压力越大,反之则越小;植被高度对高原鼠兔生境的影响力大于盖度和生物量。  相似文献   

20.
星鸦(Nucifraga caryocatactes)对红松种子进行分散贮藏、重取、建立和更新临时贮点,这一过程的研究对丰富贮食行为理论很有意义。2017年10—11月,采用红外相机监测和样方调查的方法,分析凉水国家级自然保护区星鸦对集中堆放红松球果的贮食行为、临时贮点管理以及影响贮点生境选择的主要因素。结果表明:贮藏地星鸦的重取行为比例最高,为(55.42±1.34)%,移动行为占(25.74±6.24)%,贮藏行为占(11.08±2.69)%,且有争斗行为。星鸦贮点大小为(2.39±0.09)粒,密度为(1.82±0.11)个/m^2,贮藏深度为(1.55±0.03)cm。不同生境类型(F=7.471,P<0.05)及基质类型(F=3.205,P<0.05)的贮点密度具有显著差异。贮点数量、贮点更新率最高的是距离食物源最近的人工针叶林样地。贮食距离短、频繁更新贮点、冬季之前全部重取等行为特征,是星鸦对短暂爆发性集中食物源的适应。  相似文献   

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