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21.
ABSTRACT Organic matter levels combined with drought periods during the growing season have adverse impacts on rain-fed potato production in coarse textured soils of eastern Canada. Using pulp fiber residues (PFR) may build up soil organic matter, improve crops yield and nutrient uptake, and reduce the need for supplemental irrigation in this region. A box experiment with 3 rates of PFR [0, 45, and 90 Mg ha? 1 dry mater carbon (C) basis] with or without supplementary drip irrigation was established in a sandy loam soil in New Brunswick, Canada. Red clover, barley, and potato were cultivated as three crops of the rotation in 1999, 2000, and 2001, respectively. The PFR only applied before red clover in fall 1998. Selected soil chemical and physical properties were measured before planting and after harvest. Crops yield and nitrogen (N), phosphorus (P), and potassium (K) accumulation were determined at harvest. Soil organic-C content, bulk density and water holding capacity were improved by PFR application. Red clover and barley biomass production were significantly increased by PFR application. This effect was promoted by supplemental irrigation. Potato tuber yield was not affected by PFR and it was higher in rain-fed compared to supplementary irrigated system. Although, there was some initial evidence of N immobilization but generally PFR application increased N, P, and K bioavailability. This research has demonstrated that PFR can successfully be used as soil amendment in coarse textured soils without any adverse effect. 相似文献
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制浆生物技术的研究与工业应用 总被引:16,自引:3,他引:13
综述了制浆工业中生物技术研究的发展简史,务类酶制剂在制浆工业中的研究与应用概况,着重介绍了当前制浆生物技术研究热点这一的木聚糖酶的研究与应用。同时简介了制浆生物技术的研究进展。 相似文献
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To characterize the mechanism of the reaction of lignin with aqueous acetic acid (AW) containing a small amount of H2SO4, guaiacylglycerol--guaiacyl ether (GOG), and guaiacylglycerol--syringol ether (GOS) were refluxed in 90% AW with 0.28% H2SO4 for 0–120 min. Reaction products and their silylated derivatives were characterized by analytical methods such as gas chromatography-mass spectrometry and nuclear magnetic resonance. When the model compounds were allowed to react at boiling temperature for 0 min (heat-up time 30 min), most of their primary alcohol groups and some of their secondary alcohol groups were acetylated, but their phenolic groups were not. About 90% of GOG was degraded, polymerized, or both during boiling for at least 15 min, yielding guaiacol and isocoumaran compounds (GOG-e and GOG-f) in addition to homovanillin (II) as guaiacylvinyl alcohol (I) and other minor products. GOS yielded syringol, homovanillin (II), and a novel compound (V) together with unknown products but not the corresponding isocoumaran compounds. 相似文献
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论述木片制浆生产工艺中通过利用冷喷放降低蒸煮热耗、蒸煮中期或终了汽液转注节能、放汽及喷放热能的回收利用等几种节省热能和综合利用热能的方法。制浆生产过程中的热耗主要消耗在蒸煮部分,为此,从蒸煮工艺、操作工艺入手,合理利用热能,达到提质降耗,提高经济效益的目的。 相似文献
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提出了非木材木质纤维生物质碱性亚硫酸盐制浆(ASP)生物炼制的理念,研究了总用碱量、亚硫酸化度、温度和时间对麦草碱性亚硫酸盐法蒸煮深度脱木质素特性和木质素磺化的影响。结果表明:麦草ASP法具有高的深度脱木质素选择性;深度脱木质素延伸与木质素磺化度提高具有一致性;总用碱量、亚硫酸化度、最高温度和保温时间对深度脱木质素选择性和木质素磺化度都有重要的影响;在总碱用量18.0%,亚硫酸化度85.0%,液比值3.5,最高温度168℃,保温150 min的条件下,可制得卡伯值8.8,得率56.8%,黏度为33.3 mPa.s的优良纸浆,此时黑液中磺化木质素磺酸基含量达2.16 mmol/g(以固形物计)。从深度脱木质素选择性、木质素磺化和纸浆基本特性考虑,麦草ASP法具有制浆生物炼制的前景。 相似文献
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Development of a method for sorting picea abies pulp wood with respect to basic density 总被引:1,自引:0,他引:1
《Scandinavian Journal of Forest Research》2012,27(1):65-69
The basic density of pulp wood can be used to convert green volume to dry weight, and as an indicator of the fibre quality. Because the methods for measuring basic density are cumbersome, a practical, on‐line method for sorting Norway spruce pulp wood with respect to basic density was developed. The relationship between mean annual ring width and basic density was used to sort the pulp wood. Brief visual inspection could separate piles of logs with different mean annual ring widths from each other with an acceptable precision. The resulting classes had significantly different mean basic densities (380, 400 and 434 kg m?3). Means of other properties, such as juvenile wood content, heartwood content, and dry matter content, also differed among classes. 相似文献