MY—Ⅰ型双炉烤房安装与烘烤试验初报

烤房结构不合理，不易达到烟叶烘烤工艺的要求。１９９６年我们设计安装了ＭＹ－Ⅰ型双炉烤房，并进行烘烤试验，结果表明：该烤房操作简便、控制灵活、耗煤量低、用工较少，烟叶烘烤质量明显提高。     

热风室烤房与三段式烘烤工艺配套研究初报

热风室烤房（见本刊９１．４介绍）与三段式烘烤工艺有很强的互补性，初步研究结果表明，它比普通烤房三段式烘烤、普通烤房传统烘烤公斤烟均价分别提高０．３０元、０．４８元，节煤２４．５％。二者配套是提高烟叶烘烤质量的重要技术措施，有很高的推广价值。     

热泵型烟叶烤房的设计探究

根据热泵原理设计开发了收集空气中热能的烟叶烤房。实践证明:相对于燃煤烤房,热泵烤房具有环保,降低烘烤成本和劳动强度,有效提高烘烤质量等优势。     

不同气流运动方向密集烤房烟叶烘烤质量差异研究

为比较气流上升式与气流下降式密集烤房的烟叶烘烤质量差异,开展了烟叶烘烤对比试验。结果表明,气流上升式密集烤房烤后烟叶色度更好,结构更疏松,上等烟比例要高得多;"两糖差"较小,后熟程度高;感官质量更好;中性、碱性香气成分和香气物质总量更丰富;香气指数B值更高,其烟叶烘烤质量好于气流下降式密集烤房。     

气流上升式密集烤房温湿度场分布及其对烟叶质量的影响

为明确烟叶烘烤过程烤房的温湿度场分布差异及其对烟叶质量的影响,通过在烤房内均匀放置温湿度传感器采集烘烤过程的环境温湿度数据,从垂直和水平角度分析气流上升式烤房的温湿度分布规律,并研究了烤房不同区位烟叶的烘烤质量差异。结果表明：(1)烤房垂直和水平方向的温湿度均存在显著差异,变黄前期至变黄中期差异较小,变黄后期至定色前期差异增大,定色中期至干筋后期差异减小,且烤房垂直方向的温湿度差异大于水平方向。(2)对烤房烘烤过程的温湿度时序数据进行聚类分析,可将烤房18个区位较好地分为3类,即高温低湿区域、中温中湿区域和低温高湿区域。(3)在鲜烟素质一致的条件下,烤后烟叶样品烘烤损失、上等烟比例、主要化学成分和外观评价得分整体上均没有显著性差异。(4)总糖、还原糖和淀粉含量在垂直方向有上层<中层<下层的趋势,水平方向有前端>中端>后端的趋势,两糖比值分布规律与之相反;垂直方向下层烟叶存在颜色纯正度、柔软度和油润感得分较高的趋势,水平方向中端烟叶存在颜色纯正度、光泽度、柔软度和油润感得分较高的趋势。基于烤房温湿度分布规律研究,有助于为烤房合理分类装烟和烘烤工艺仿真提供数据支撑。     

关于烤房结构和烧煤方法问题的商榷

影响烟叶烘烤质量的因素很多，本文根据在福建省三明烟区的实践和调查，主要从烤房结构、通风排湿设备及烧煤方法进行改革和试验，改变了过去的一些习惯作法，使烟叶的烘烤质量得到提高。     

变频电机对密集烘烤烟叶质量的影响

为了解决密集烤房风机风速风量过大的问题,对密集烤房循环风机加装变频器,研究各烘烤阶段不同变频频率对烟叶烘烤质量的影响。结果表明,烘烤过程中烤房烟叶叶隙间风速能相对稳定在0.2～0.5 m/s范围内,变黄和定色时间整体拉长10 h,烟叶外观质量得到提高,橘黄烟和成熟度比例均提高7个百分点,疏松度增加4个百分点,烟叶内在化学成分得到改善,总糖和还原糖分别提高1.1个百分点和3个百分点,淀粉含量降低0.7个百分点,烟叶感官评吸质量明显转好。     

不同烘烤方法对烟叶质量及香味成分的影响

为了改进烘烤方法,提高烟叶烘烤质量,研究了延时密集烘烤、普通密集烘烤及小烤房传统烘烤3种烘烤方法对烤后烟叶质量及香味成分含量的影响。结果表明,在密集烘烤过程中,适度延长变黄期和定色期稳温时间,可提高烟叶外观质量及感官质量,化学成分更趋协调,同时有利于提高烟叶质体色素、西柏烷类及苯丙氨酸类的降解产物含量。     

高效节能蜂窝煤烤房技术研究

笔者分析总结多年改造烤房经验，参阅有关技术资料，在常规烤房、一般节能烤房的基础上，研究设计改建成功高效节能蜂窝煤烤房。该烤房经１９８９～１９９１年３年的实践表明，烘烤每公斤干烟平均用标煤１．５８ｋｇ，较常规烤房节煤５２．２７％；烤后烟叶内在质量与常规烤房所烤烟叶内在质量基本接近；上等烟增加８．７％；公斤干烟均价提高０．２４５６元；每亩降低生产成本２５．３９元；亩烟叶增值４２．９９元，取得显著的经济效益。     

新型内置一体式生物质密集烤房烘烤效果研究

为减少烤房能耗过高和污染等问题,采用新型内置一体式生物质密集烤房,与燃煤、外置式生物质密集烤房在烘烤性能、废气排放、烤后烟叶产质量、综合效益等方面进行了对比研究。结果表明,新型内置一体式生物质密集烤房稳温性能优于燃煤密集烤房,与外置式生物质烤房性能相当;综合热效率分别提高了12.54%和5.01%,干烟用工成本分别降低了88.98%和10.80%,烤后烟叶均价分别提高了1.89和0.26元/kg,烤后烟叶油分略有提升、杂气略有减轻,烟叶烘烤平均净均价分别增加2.63和0.46元/kg;中部烟叶烘烤过程中4种有害废气总含量分别降低了9 235.70和1 524.73 mg/m³。因此,新型内置一体式生物质密集烤房烘烤效果最佳,更具有推广价值。     

Arsenic(III) oxidation by iron(VI) (ferrate) and subsequent removal of arsenic(V) by iron(III) coagulation

We investigated the stoichiometry, kinetics, and mechanism of arsenite [As(III)] oxidation by ferrate [Fe(VI)] and performed arsenic removal tests using Fe(VI) as both an oxidant and a coagulant. As(III) was oxidized to As(V) (arsenate) by Fe(VI), with a stoichiometry of 3:2 [As(III):Fe(VI)]. Kinetic studies showed that the reaction of As(III) with Fe(VI) was first-order with respect to both reactants, and its observed second-order rate constant at 25 degrees C decreased nonlinearly from (3.54 +/- 0.24) x 10(5) to (1.23 +/- 0.01) x 10(3) M(-1) s(-1) with an increase of pH from 8.4 to 12.9. A reaction mechanism by oxygen transfer has been proposed for the oxidation of As(III) by Fe(VI). Arsenic removal tests with river water showed that, with minimum 2.0 mg L(-1) Fe(VI), the arsenic concentration can be lowered from an initial 517 to below 50 microg L(-1), which is the regulation level for As in Bangladesh. From this result, Fe(VI) was demonstrated to be very effective in the removal of arsenic species from water at a relatively low dose level (2.0 mg L(-1)). In addition, the combined use of a small amount of Fe(VI) (below 0.5 mg L(-1)) and Fe(III) as a major coagulant was found to be a practical and effective method for arsenic removal.     

Mind the (yield) gap(s)

This paper explores the origin of the notion of ??yield gap?? and its use as a framing device for agricultural policy in sub-Saharan Africa. The argument is that while the yield gap of policy discourse provides a simple and powerful framing device, it is most often used without the discipline or caveats associated with the best examples of its use in crop production ecology and microeconomics. This argument is developed by examining how yield gap is used in a selection of recent and influential agricultural policy documents. The message for policy makers and others is clear: ??mind the (yield) gap(s)??, for they are seldom what they appear.     

Iron(VI) and iron(V) oxidation of copper(I) cyanide

Copper(Il) cyanide (Cu(CN)4(3-)) in the gold mine industry presentsthe biggest concern in cyanide management because it is much more stable than free cyanide. Cu(CN)4(3-) is highlytoxic to aquatic life; therefore, environmentally friendly techniques are required for the removal of Cu(CN)4(3-) from gold mine effluent. The oxidation of Cu(CN)4(3-) by iron-(VI) (FeVIO4(2-), Fe(VI)) and iron(V) (FeVO4(3-), Fe(V)) was studied using stopped-flow and premix pulse radiolysis techniques. The stoichiometry with Fe(VI) was determined to be 5HFeO(4-) + Cu(CN)4(3-) + 8H2O - > 5Fe(OH)3 + Cu2+ + 4CNO- +3/202 + 6OH-. The rate law for the oxidation of Cu(CN)4(3-) by Fe(VI) was found to be first-order with each reactant. The rates decreased with increasing pH and were mostly related to a decrease in concentration of reactive protonated Fe(VI) species, HFeO4-. A mechanism is proposed that agrees with the observed reaction stoichiometry and rate law. The rate constant for the oxidation of Cu(CN)4(3-) by Fe(V) was determined at pH 12.0 as 1.35 +/- 0.02 x 10(7) M(-1) s(-1), which is approximately 3 orders of magnitude larger than Fe(VI). Results indicate that Fe(VI) is highly efficient for removal of cyanides in gold mill effluent.     

Supercritical fluid extraction (SFE) of 4(5)-methylimidazole (4-MeI) and 2-acetyl-4(5)-(1,2,3,4)-tetrahydroxybutyl-imidazole (THI) from ground-coffee with high-performance liquid chromatographic-electrospray mass spectrometric quantification (HPLC/ESI-MS).

Two polar analytes, 4(5)-methylimidazole (4-MeI) and 2-acetyl-4(5)-(1,2,3,4)-tetrahydroxybutyl-imidazole (THI), were extracted with supercritical carbon dioxide (CO2) modified with aqueous methanol. The method was applied to a roasted coffee powder with good recovery rates. Method efficiency was compared with that of solid-phase extraction using SCX Disc cartridges and validated for spiked solid matrix. The analytes were determined using isocratic liquid chromatography-mass spectrometry (LC/MS) on an Atlantis HILIC Silica column (150 x 2.1 mm, 3 microm) with 80% methanol and 20% 0.01 mol l-1 ammonium formate as the mobile phase. The limit of quantification was around 1.5 pg for 4-MeI and 2.0 pg for THI. The linearity of the calibration curves was satisfactory as indicated by correlation coefficients of >0.999. The coefficient of variation for the intra-day and inter-day precisions was <4% (n = 6). Accuracy was in the range 98-101%; recovery rates were > or = 98 and > or = 99% for THI and 4-MeI, respectively. Several samples of Arabica coffee from various locations and commercially available 'off-the-shelf' coffee products (Arabica/Robusta mixtures) were analysed to test the method.     

Reduction of Tc(VII) by Fe(II) sorbed on Al (hydr)oxides

Under oxic conditions, Tc exists as the soluble, weakly sorbing pertechnetate [TcO4-] anion. The reduced form of technetium, Tc(IV), is stable in anoxic environments and is sparingly soluble as TcO2 x nH2O(s). Here we investigate the heterogeneous reduction of Tc(VII) by Fe(II) adsorbed on Al (hydr)oxides [diaspore (alpha-AlOOH) and corundum (alpha-Al2O3)]. Experiments were performed to study the kinetics of Tc(VII) reduction, examine changes in Fe surface speciation during Tc(VII) reduction (M?ssbauer spectroscopy), and identify the nature of Tc(IV)-containing reaction products (X-ray absorption spectroscopy). We found that Tc(VII) was completely reduced by adsorbed Fe(II) within 11 (diaspore suspension) and 4 days (corundum suspension). M?ssbauer measurements revealed thatthe Fe(II) signal became less intense with Tc(VII) reduction and was accompanied by an increase in the intensity of the Fe(III) doublet and magnetically ordered Fe(III) sextet signals. Tc-EXAFS spectroscopy revealed that the final heterogeneous redox product on corundum was similar to Tc(IV) oxyhydroxide, TcO2 x nH2O.     

优质农业生产管理指导手册(二)

4病虫害综合防治 病虫害综合防治(IPM)是烟叶生产的一项系统体系,利用病虫害预测预报系统,提供最好的病虫害综合防治决策,重点是协调应用一切可行的办法.病虫害综合防治并不意味着完全排除使用农药,而是在使用其它办法不能使病虫害的种群数保持在可接受的范围时适当使用农药.施用农药的地方应确保安全,并遵守一切法律法规.     

优质农业生产管理指导手册

优质农业生产管理体系(GAP)概念提出的目的在于确保烟叶生产的持续、健康发展,可以将GAP定义为:在保护、维持或增强土壤、水源、空气、动植物生命和环境的同时,在确保农业生产可持续发展的条件下,推行一系列农业措施,生产出一定产量和质量的优质农作物.     

Reactivity of Pb(II) at the Mn(III,IV) (oxyhydr)oxide--water interface

In this study, the reactivity of lead (Pb(II)) on naturally occurring Mn(III,IV) (oxyhydr)oxide minerals was evaluated using kinetic, thermodynamic, and spectroscopic investigations. Aqueous Pb(II) was more strongly adsorbed to birnessite (delta-MnO1.7) than to manganite (gamma-MnOOH) under all experimental conditions. The isoteric heat of Pb adsorption (delta HT) or birnessite was 94 kJ mol-1 at a surface loading of 1.1 mmol g-1, and decreased with increasing adsorption density. This indicated that adsorption was an endothermic process and that birnessite possessed heterogeneous sites of reactivity for Pb. X-ray absorption fine structure (XAFS) spectra revealed that Pb was adsorbed as inner-sphere complexes on both birnessite and manganite with no evidence to suggest oxidation as an operative sorption mechanism. Lead appeared to coordinate to vacancy sites in the birnessite layer structure with concurrent release of Mn to solution, which resulted in a greater number of second shell Mn scatterers in Pb-birnessite when compared to Pb-manganite samples. The difference in Pb coordination apparently explained the contrasting desorption behavior between the two Mn minerals. These results have significant implications for Pb partitioning in soil environments containing solid-phase Mn(III,IV) (oxyhydr)oxides.     

全棉自然弹技术与风暴牛仔

<正>全棉自然弹(Natural StretchTM)技术,运用于全棉面料,例如纯棉牛仔面料。通过调整面料生产的工艺流程,无需热定形或添加氨纶丝,即可达到10%～30%的舒适弹性,其最大优势在于降低生产成本的同时,使面料具有弹性。风暴牛仔(Storm DenimTM)是一项用于100%纯棉牛仔的超级防水透气整理技术,可以保护穿着者不受