掺混肥料

范围本标准规定了掺混肥料的要求、试验方法、检验规则、标识、包装、运输和贮存。本标准适用于氮、磷、钾三种养分中至少有两种养分标明量的由干混方法制成的冠以各种名称的肥料,适用于缓释型、控释型及有机质质量分数未超过20%的掺混肥料;本标准适用于干混补氮     

中,低浓度掺混肥的生产及优势

掺混肥是一种由含不同养分的颗粒肥料掺混而成的复混肥 ,它是将一定粒径的基础肥料 ,根据土壤的养分状况和作物需求定配方 ,按照一定的比例掺混而成。这种生产方法 60年代起源于美国 ,它不仅改变了美国化学工业的面貌 ,而且引起了世界各国的极大关注 ,在美国主要以几种颗粒状的单一肥料或复合肥料生产散装掺混肥料 ,又称ＢＢ肥。ＢＢ肥属高浓度掺混肥 ,如嘉吉ＢＢ肥以美国二铵 ,苏联尿素、碳铵为基础肥料生产 ,总养分含量可达 57%。在美国 ,80年代初大约有 50 0座ＢＢ肥生产装置 ,生产量为 1 92 3万吨 ,占美国总肥料销量的42 % ,占美国复混…     

国外含镁大量元素肥料产品现状分析

对14家世界知名大型肥料企业的869组大量元素肥料产品信息数据分析表明,国外重视镁在大量元素肥料产品中的添加,含镁大量元素肥料产品占比为54.7%。在养分含量方面,国外大量元素肥料中镁养分平均含量为2.4%MgO,且在不同肥料类型、不同适宜作物肥料产品之间,镁养分含量没有明显差异;在养分形态方面,在复混肥、水溶肥和叶面肥中,镁形态以硫酸镁为主,在掺混肥料中,镁形态以硫酸镁+氧化镁共存形式为主;在养分配比方面,氮镁比、钾镁比主要在5～8之间,占比分别为35.8%和29.3%,磷镁比主要在2～5之间,占比为53.9%。分析结果可为我国含镁肥料研发提供参考。     

介绍掺混肥料的取样器

掺混肥料在包装、运输途中 ,由于不同基础物料在物理性质上存在差异 ,引起肥料在垂直和水平方向上不同养分含量的分离。所以 ,掺混肥料属于定向非随机不均匀物料。根据掺混肥料的定向非随机不均匀性 ,对于件装掺混肥料 ,我们采取“四角取样法”取样 ,即按采样袋数 =3 3N (N 每批产品总袋数 )计算结果 ,随机抽取一定袋数 ,将袋平放 ,用采样器从每袋的 4角处依次沿最长对角线插入至袋的 3 /4 ,取出不少于 10 0 g样品 ,每批采样品量不得少于 8kg。在掺混肥料的取样中 ,取样器的选择尤为重要。如图 1所示 ,采用改进的可封闭的采样探子。该采样…     

掺混肥料在我国农业生产规模化进程中的发展前景探讨

我国最新土地流转政策的出台必将推动农业生产规模化进程,在此背景下,从环境、粮食增产、养分全面、配方灵活、生产成本低等方面阐述了掺混肥料发展因素,探讨了掺混肥料向有机无机型、缓控释型、多功能型及测土配方型的发展趋势及其发展前景,并认为掺混肥将会成为今后肥料需求及发展的首选。     

不同养分释放期控释尿素掺混后的养分释放特征

以3种养分释放期不同的控释尿素为供试肥料,采用化工行业标准《控释肥料》(HG/T 4215—2011)中规定的25℃静水浸提凯氏定氮法和100℃快速浸提凯氏定氮法,试验研究了不同养分释放期控释尿素的不同掺混比例对养分释放特征的影响。试验结果表明:几种控释尿素掺混后养分释放率的实测值与按比例加权值计算的释放率相当,通过100℃静水浸提法也可快速预测掺混控释尿素在25℃静水中的养分释放期;不同养分释放期的控释尿素掺混后,其养分释放期仍与养分释放期较长的那种控释尿素相同,养分释放高峰点出现时间与不同养分释放期控释尿素掺混比例有关;根据不同养分释放期控释尿素时段溶出的养分加权值计算不同时段的养分释放率,所得预测值与实测释放率基本一致;对于掺混控释尿素,养分释放期较长的控释尿素掺混一定比例的养分释放期相对较短的控释尿素,可在作物前期或在作物快速生长期出现养分释放高峰,更好地满足作物养分最大效率期对养分的需求,弥补单一长效控释尿素前期养分供应不足的缺点,使控释肥养分释放与作物各生育期对养分的需求相同步。     

掺混肥料采样探子的设计与使用

由于掺混肥料所使用的不同基础物料的颗粒粒径、表观密度、均匀度、圆润度等各不相同，在生产、包装、运输途中，容易引起物料在水平和垂直方向上不同养分的分离，所以掺混肥料属于定向非随机不均匀物料（见GB／T6678—2003）。鉴于此，掺混肥料的取样必须选择可封闭式的采样探子，才能取出不同部位的有代表性的样品。     

掺混肥料生产新技术和发展前景

介绍了涂布技术生产氮钾颗粒肥料的方法。同时应用氮磷、氮钾颗粒肥料作为发展多品种掺混肥料的基础肥料,以更好地满足农作物和土壤对养分的需求。     

我国复混肥料产品时空特征及发展趋势

研究我国复混肥料产品(特指含有3种及以上养分的复合肥料、掺混肥料、有机-无机复混肥料)2009-2019年的发展状况.结果表明:截至2020年1月1日,我国复混肥料企业达到3318家,比10年前增加了1.7％,复合肥料企业数量减少了 36.1％,掺混肥料企业增加了 181.2％;2015-2019年登记的肥料产品数量达...     

掺混肥料检验方法的改进

由于掺混肥属于定向非随机不均匀物料,为使养分分析结果具有代表性,重现性好,提出掺混肥料取样方法的改进措施,选择可封闭式或关闭式采样探子;采用四角取样法进行取样;采用多次重新缩分的分样方式进行样品缩分;试样制备时保留至少200~250 g样品。用此方法对掺混肥取样分析,可获得较好的结果。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。