牵住市场的“牛鼻子”加快发展市场农业

牵住市场的“牛鼻子”加快发展市场农业袁剑文牵住市场的“牛鼻子”，加快发展市场农业，就是全面分析研究市场特征，把握市场规律，摸透市场的“牛脾气”，正确引导调控市场经济，促进市场农业快速稳定地发展，它与“跟着市场走”、“围着市场转”有着本质的区别。第一工...     

小麦市场总体平稳

我国的小麦市场总体上仍是一个供求基本平衡、略有结余的市场。短期内随着托市收购的结束，收储企业小麦轮换补库的完成，制粉企业的小麦采购相对理智，市场的需求会有所减弱，小麦市场价格可能会平稳调整，但幅度不会很大。从中长期看，国内小麦市场在国家市场调控引导下，局部市场波动虽不可避免，但整体市场平衡运行的大局则不会改变。     

农业市场模式初探

农业市场发育壮大的快慢，事关全局，如果不把农民引向市场，就打不开农业市场，就打不开中国市场。也难以与国际市场并网接轨。本文是在调研的基础上，对现有的八种农业市场模式作了初步探索。     

制约农民进入市场的“三个因素”

农民发展商品经济创造了市场的繁荣，农民的生产、生活也日益依赖于市场。但仍然有一些制约因素阻碍农民进入市场，江西赣州南方工业学校财经科张风雨来稿认为，有下面三个制约因素：其一是市场不健全，功能不完善，地区封锁严重。突出表现在市场少、规模小。大多数地方的农产品市场只有集市贸易，零售市场。这类市场容量小，辐射范围狭窄，难以满足农产品的供求需要。同时一些地方市场封锁严重影响全国大市场的形成，限制了农产品大范围的流通，农民处于不利地位。其二是信息不灵，农业生产经营的波动性较大，市场信息是农业生产经营的指挥…     

转变观念 抓住机遇 主动迎接市场的挑战——买方市场条件下农业发展的对策选择

改革开放以来，我国经济经过高速增长的量变积累，已经出现了质的变化，从根本上摆脱了短缺经济状态，市场供求格局由过去的卖方市场变成了买方市场。农业生产者和组织者必须正确认识当前农产品市场新形势，转变市场经营观念，以市场为导向，及时调整农业生产思路，抓住市场机遇，主动迎接市场的挑战。     

棉价上涨空间不大

近期，随着阴雨天气的结束，南方地区籽棉收购市场活跃。由于籽棉资源逐步减少，市场上量价齐涨。相比南方市场的火热，北方市场略显温和，市场上籽棉收购价格略有小涨，但成交量一般；皮棉销售价格略有调整，成交量也有所减少。     

农产品营销“七招”

1．市场转移。当淡季到来时，可以进行市场转移，寻找适合产品的新市场，甚至进入国际市场。例如夏装，当我国北方地区进入冬季时，东南亚地区夏装仍在畅销，此时如果将销售重心转移，就可获得不错的市场回报。     

谈新品种推广技巧

当今种子市场纷繁复杂，品种众多，且新品种层出不穷，要将新品种快速打入市场、占有市场，只有掌握一套行之有效的推广技巧．才能成功打开市场和占有市场。     

近期国内大豆市场变化莫测

玉米市场价格稳中有升，小麦市场价格日趋明朗化，所不同的是，国内大豆市场近期可谓是风云突变。第一船巴西大豆在广东赤湾港开始卸货，这一消息在国内大豆市场可谓是一石激起千层浪，大豆价格后期走势更是让人云里雾里，市场上对价格走势的推测也是说法不一，虽然进口大豆已经进入我国市场，但近期对市场的影响不会太大，具体原因如下：近期国内大豆市场价格受进口影响不会太大。自去年６月份转基因政策颁布以来，中国的大豆进口一直为市场关注，而今年３月２０日转基因条例正式实施后，转基因大豆进口则陷入停滞状态，国内大豆市场供应面…     

完善农产品市场体系建设

农产品市场体系建设，直接影响农产品的生产和发展。完善农产品市场体系建设应从农产品市场、信息系统、产品标准和认证体系、行业商会、农村信贷等方面入手，通过优化农业产业结构，建立网上市场窗口，制定市场法规，进行技术培训等方式来培育农产品市场体系。     

不同基因型小麦苗期耐低氮性评价及筛选

氮素作为重要的营养元素,限制着小麦的生长发育和经济产量,筛选和培育耐低氮小麦品种是提高氮素利用率、降低生产成本的有效途径。以118份不同基因型小麦为材料,在低氮(0.1 mmol·L^-1)和正常氮(5 mmol·L^-1)条件下苗期水培,测定根干重、茎叶干重、根冠比、植株干重、最大根长、初生根数和二级初生根数等相关指标,采用模糊隶属函数法、主成分分析以及聚类分析法综合评价小麦品种的耐低氮性。结果表明,在低氮胁迫下小麦幼苗的根干重、根冠比和初生根数目显著提高,茎叶干重、植株干重和最大根长不同程度的降低,7个苗期性状指标在两个氮水平下均存在显著性差异。主成分分析提取3个主成分,贡献率分别为 43.575%、22.904%和17.873%,累积贡献率达 84.351%。以耐低氮性综合评价D值进行聚类分析,将118份小麦品种划分为强耐低氮型、耐低氮型、中间型、较敏感型和敏感型5类。筛选出3份耐低氮型小麦（齐大195、金丰7183和天民198）和2份强耐低氮型小麦（山农0917和鲁麦8号）。不同小麦品种的耐低氮机制不同,研究结果为小麦耐低氮品种的选育提供理论依据和材料基础。     

一串红N、P、K、Ca、Mg、Fe缺素症状研究

以‘展望红’为材料,研究N、P、K、Ca、Mg、Fe缺乏对其生长发育的影响,并总结缺素症状,研究结果表明:N缺乏时植株矮小,叶发黄;P缺乏时叶色暗绿,且影响开花;K缺乏时基部叶枯黄,并易落叶;缺Fe症状较为明显,但能正常开花;Ca、Mg未表现出缺素症状,且各项指标要优于全素处理;N、P显著影响一串红的生长发育,K对开花品质的影响较大。     

Segregation of form, color, movement, and depth: anatomy, physiology, and perception

Anatomical and physiological observations in monkeys indicate that the primate visual system consists of several separate and independent subdivisions that analyze different aspects of the same retinal image: cells in cortical visual areas 1 and 2 and higher visual areas are segregated into three interdigitating subdivisions that differ in their selectivity for color, stereopsis, movement, and orientation. The pathways selective for form and color seem to be derived mainly from the parvocellular geniculate subdivisions, the depth- and movement-selective components from the magnocellular. At lower levels, in the retina and in the geniculate, cells in these two subdivisions differ in their color selectivity, contrast sensitivity, temporal properties, and spatial resolution. These major differences in the properties of cells at lower levels in each of the subdivisions led to the prediction that different visual functions, such as color, depth, movement, and form perception, should exhibit corresponding differences. Human perceptual experiments are remarkably consistent with these predictions. Moreover, perceptual experiments can be designed to ask which subdivisions of the system are responsible for particular visual abilities, such as figure/ground discrimination or perception of depth from perspective or relative movement--functions that might be difficult to deduce from single-cell response properties.     

ICP-OES法同时测定果蔬中铅、砷、镉、铬、铜、锡含量

果蔬样品经混酸消化后,控制一定的酸度,定容后应用等离子体发射光谱法(ICP-OES)对果蔬中铅、砷、镉、铬、铜、锡六种有害重金属进行测定,研究了分析测定条件,方法简单快速。测定结果表明,五种元素的加标平均回收率在91.0%~107%之间。其RSD均小于3.5%。按该方法进行处理及测定铅、砷、镉、铬、铜、锡,在选择的测定条件下最低检出限分别为0.0006 mg/kg、0.0003 mg/kg、0.00003 mg/kg、0.00005 mg/kg、0.00003 mg/kg、0.0006 mg/kg。     

贵州樟科、景天科等9个科药用植物资源的种类与分布

通过野外调查、标本采集、分类学研究及资料考证,基本摸清了贵州樟科、莲叶桐科、景天科、堇菜科、柳叶菜科、鹿蹄草科、柿科、山矾科、木犀科等9个科药用植物资源的种类与地理分布.结果发现贵州现有樟科药用植物49种4变种,莲叶桐科药用植物5种,景天科药用植物21种,堇菜科药用植物19种1变种,柳叶菜科药用植物20种4变种,鹿蹄草科药用植物7种1变种,柿科药用植物9种1变种,山矾科药用植物12种,木犀科药用植物30种3变种.其中,4种为贵州特有药用植物,40种5变种为贵州药用新资源.     

Fiber, food, fuel, and fungal symbionts

Virtually all plants of economic importance form mycorrhizae. These absorbing organs of higher plants result from a symbiotic union of beneficial soil fungi and feeder roots. In forestry, the manipulation of fungal symbionts ecologically adapted to the planting site can increase survival and growth of forest trees, particularly on adverse sites. Vesicular-arbuscular mycorrhizae, which occur not only on many trees but also on most cultivated crops, are undoubtedly more important to world food crops. Imperatives for mycorrhizal research in forestry and agriculture are (i) the development of mass inoculum of mycorrhizal fungi, (ii) the interdisciplinary coordination with soil management, plant breeding, cultivation practices, and pest control to ensure maximum survival and development of fungal symbionts in the soil, and (iii) the institution of nursery and field tests to determine the circumstances in which mycorrhizae benefit plant growth in forestry and agri-ecosystems.     

中美贸易争端对河北省小麦市场影响分析

中美贸易是全球范围内影响最大的贸易之一。随着美国总统提出“美国优先”政策,两国间的贸易争端不断升级。美国对中国进口产品实施加征关税,根据对等原则,2018 年6 月18 日中国将美麦列入进口加征关税清单。文章通过对河北省小麦产业发展优势和存在问题的分析,研究美麦进口价格的提高对中国小麦主产省份——河北省造成的影响。通过与美国小麦进行比较看出,短期内进口美麦加征关税对河北省小麦产业影响不大;从长期看,对河北省小麦产业发展利大于弊,可以促进河北省优质麦产业发展。基于此,文章从优质麦产业化经营、标准化体系建设、扩大一带一路国家小麦进口等方面提出相应的对策和建议,推进河北省优质麦产业的发展。     

Space, stars, c60, and soot

Although carbon has been subjected to far more study than all other elements put together, the buckminsterfullerene hollow-cage structure, recently proposed to account for the exceptional stability of the C(60) cluster, has shed a totally new and revealing light on several important aspects of carbon's chemical and physical properties that were quite unsuspected and others that were not previously well understood. Most significant is the discovery that C(60) appears to form spontaneously, and this has particularly important implications for particle formation in combustion and in space as well as for the chemistry of polyaromatic compounds. The intriguing revelation that 12 pentagonal "defects" convert a planar hexagonal array of any size into a quasi-icosahedral cage explains why some intrinsically planar materials form quasi-crystalline particles, as appears to occur in the case of soot. Although the novel structural proposal has still to be unequivocally confirmed, this article pays particular attention to the way in which it provides convincing explanations of puzzling observations in several fields, so lending credence to the structure proposed for C(60).     

Strategic command, control, communications, and intelligence

Command, control, communications, and intelligence (C(3)l) for nuclear forces are essential elements in the deterrence of nuclear war. The present C(3)l) system has vulnerabilities associated with its reliability, survivability, and endurance under attack, thereby weakening deterrence by increasing the ambiguity in our capabilities. Development of a reliable and enduring C(3)l) system would reduce this ambiguity. Its reliable, positive control of nuclear forces would give the national leadership more time to assess situations, ensure discriminate retaliation, and improve our ability to manage crises in general. These capabilities could help to stop a war rapidly should one start. A reliable and enduring C(3)1) system will be needed for a long time to come, even if a freeze on strategic nuclear forces is accomplished or other arms control successes achieved. Indeed, C(3)l) may be the best source today of confidence-building measures to reduce tensions and the threat of nuclear catastrophe.     

重金属稀土元素污染在水生物体内的生物富集

对铅、镉、汞以及镧、铈在鲤鱼体内的生物富集作用进行了室内试验和讨论。结果表明,重金属及稀土元素在鱼体各部位均有较强的富集作用,其中肌肉部分富集能力较弱,内脏富集能力最强;鱼体各部位对重金属及稀土元素的富集作用随时间的增加而增加,在一定的时间后趋于平衡;并且,鱼体中各部位对重金属及稀土元素的生物富集作用存在较大差异。