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1.
为合理利用剑麻麻茎作有机肥还田,采用盆栽试验研究了麻茎单独还田及配施不同用量氮肥对土壤理化性质和剑麻生长的影响。结果表明,单加麻茎处理土壤有机质含量、碱解氮含量和土壤脲酶活性与空白对照相比均显著提高,增幅分别达180.0%、46.8%、109.7%。麻茎配施不同水平尿素也明显提高土壤有机质含量、碱解氮含量和土壤脲酶活性。麻茎配施1/2用量尿素可显著提高土壤转化酶活性。麻茎配施1/4用量尿素明显提高剑麻叶长,分别比空白对照、单施尿素和单施麻茎处理提高60.9%、25.0%、22.5%。添加麻茎可以在一定程度上取代尿素的施用,在添加麻茎的情况下,不需要施用全量化肥。 相似文献
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《Industrial Crops and Products》2006,23(3):318-326
The Athel tree, Tamarix aphylla (L), can potentially be used as a biomass crop to help manage saline subsurface drainage water in arid land irrigated agriculture. In this study, Athel wood was used to manufacture medium-density particleboard with an aim of developing new applications for the saline wood. The research investigated the effects of different types of adhesives, particle sizes, bark content (BC), resin content (RC), and hot water pretreatment on the mechanical and water resistance properties of the Athel-derived, medium-density particleboards. The measured mechanical properties included tensile strength (TS), modulus of rupture (MOR), modulus of elasticity (MOE), and internal bond strength (IB) of the finished particleboards. Water absorption and thickness swell were used to evaluate the water resistance. Polymeric methane diphenyl diisocyanate (PMDI) resin made particleboard of better mechanical properties and water resistance than urea formaldehyde (UF). The medium size (20–40 mesh) particles gave the best mechanical properties and water resistance than of the particleboard when evaluated against the smaller size (40–60 mesh) and larger size (10–20 mesh) particles. The mechanical properties of particleboard were improved as the resin content of the UF-board increased from 7 to 16%, but deteriorated as the bark content increased from 0 to 16.2%. The particleboard made from the wood particles that had undergone hot water pretreatment had poor mechanical properties and water resistance compared with the particleboard made from the untreated particles. Saline Athel wood is an appropriate material for manufacturing particleboards. 相似文献
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《Industrial Crops and Products》2001,13(3):209-218
Castor (Ricinus communis L.) stalks, which are a readily available by-product of this plant mainly cultivated for seed production, derived from experimental plantations grown in Northern Greece during the period April–October 1996 were assessed for their suitability as feed stocks for direct substitution of wood in particleboard. The average stalk yield of castor reached about 10 dry t/ha, which is higher than the average yield of forest in temperate zones. After harvesting, castor stalks were dried in a greenhouse to about 12% moisture content, and chipped by an automobile chipper and re-chipped in a hammermill. Castor particles and industrial wood particles mixed in various proportions were used as raw material for one-layer and for the middle layer of three-layer particleboards. A commercial E2 grade UF-resin was used as binder. Castor particles were characterized by a lower slenderness ratio and lower bulk density than industrial wood particles. The evaluation of the mechanical and hygroscopic properties of panels showed the following results: Partial substitution of wood by castor stalks resulted in the deterioration of all board properties. The presence of the unlignified pith and the configuration of castor particles seem to be responsible for the deleterious effect of castor stalks on board properties. However, comparing the properties of the boards produced in this study to relevant European and American Standards, it was found that, with the exception of screwholding strength for three-layer boards, the experimental one layer-, and three-layer boards containing up to 25% and 75% castor particles respectively meet or exceed the Standards requirements for interior boards. 相似文献
4.
In this study, influence of impregnating wood particles with mimosa bark extract on the some properties of particleboard was investigated. Properties evaluated were modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB), thickness swelling (TS), and formaldehyde emission (FE). The results showed that particleboards made from particles impregnated with mimosa bark extract had significantly lower mechanical, physical and formaldehyde emission values than those of the boards made from unimpregnated particles. Brushing of mimosa bark extract to the surfaces and edges of the particleboards did not affect the mechanical properties, statistically. However, this application caused a significant improvement in the thickness swelling and formaldehyde emission. 相似文献
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J.A. Flores J.J. PastorA. Martinez-Gabarron F.J. Gimeno-BlanesI. Rodríguez-Guisado M.J. Frutos 《Industrial Crops and Products》2011,34(3):1538-1542
Common reed (Arundo donax) is a fast growing perennial plant, considered in many countries as a weed or invasive plant. New material developments in recent years have led to common cane proliferation and an invasion in crops and water channels, significantly increasing elimination and control costs. In this study, it is proposed that particleboard be manufactured of common reed (A. donax). The objective is twofold. On the one hand it allows control of a weed, and secondly, it helps reduce the high dependence of imported wood timber and boards by using a readily and annually renewable resource.The fibers of common reed A. donax, possess high tensile strength (200 N/mm2 between knots), providing much higher values than wood. This fact together with an important moisture and aging resistance, encourage us to propose it as a suitable raw material for the production of particleboards. In this study we propose the manufacture of particle board with urea formaldehyde resin, which is currently used in the wood chipboard industry.To perform this study, A. donax fibers obtained from a shredding hammer, were classified attending to size and slenderness. Following the standard industrial chipboard manufacturing processes, boards were developed to compare their behaviour against wood chipboards. Fifteen test-tube batches with different proportions of pre-selected fibers were manufactured. New boards were subjected to a mechanical stress test, and other physical properties were also measured. UNE EN—specific wood chipboard regulations were applied.Results showed that particleboard could be manufactured using A. donax adjusting the particle size to a maximum of 4 mm sieves. Finally it can be stated that making common reed panels also involves the reuse of a plant actually considered a weed, to become a raw material for industrial applications, leaving a door open to future development and research areas. 相似文献
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为促进茶梗的高效利用,对黑曲霉利用茶梗固态生料发酵生产单宁酶进行初步研究。结果表明：生料发酵产酶量是熟料发酵方式的3.2倍;茶梗中外加单宁酸对产酶没有明显影响,同时添加无机盐和碳氮源对产酶具有协同效应;蔗糖为产酶最佳碳源,但在产酶初期会对单宁酶的合成产生一定的抑制作用;氯化铵为产酶最佳氮源,在培养基中添加氯化铵既可提前单宁酶合成的时间,又可显著提高酶产量。添加质量分数为7%的蔗糖和氯化铵获得最高酶产量23.6 U·g-1。试验结果为茶梗固态生料发酵产单宁酶奠定了一定的理论基础,并有助于促进对茶梗的规模化开发和利用。 相似文献
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秸秆深还对土壤水分转移及产量的影响 总被引：7，自引：2，他引：5
采用田间试验方法,将玉米秸秆切段、粗粉碎、细粉碎、细粉碎后压粒和细粉碎后氨化处理,研究玉米秸秆深施还田对土壤水分转移及产量的影响。结果表明,秸秆粉碎程度越细,吸水能力越强,深施后土壤渗水速度越快;粉碎的秸秆较其他处理更能促进土壤水分竖直方向转移;各处理的蓄水能力表现为粉碎状秸秆处理段状秸秆处理CK(不施秸秆),且细粉碎、细粉碎后氨化处理在还田初期就能呈现出明显的蓄水效果;秸秆粉碎状态越细,深施后土壤容重减小的速度和幅度越大,细粉碎处理和细粉碎后氨化处理能在还田初期对减小土壤容重产生明显作用,播种后25 d,土壤容重减小幅度最大,分别达0.052和0.045 g/cm3;秸秆深施还田有效提高玉米产量,产量排序为细粉碎细粉碎后氨化处理粗粉碎细粉碎后压粒秸秆切段CK(不施秸秆),其中细粉碎处理对玉米产量的增加影响最明显。 相似文献
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通过连续两年开展田间定位试验,在减氮20%的条件下比较不同增效氮肥对玉米产量、氮素回收率与损失率、氨挥发及土壤无机氮残留量的影响。结果表明,与常规氮肥处理相比,减氮施用稳定性氮肥、硅酸盐包膜尿素、肥包肥不影响玉米子粒产量和植株吸氮量,氨挥发量分别下降35.6%、43.0%和39.9%;氮素表观利用率分别达到43.8%、42.4%和44.6%,明显高于常规氮肥处理的35.8%,因此具有较好的应用潜力。施用脲甲醛氮肥损失率较高,减氮施用后造成减产,不适合本研究所在区域的土壤和气候条件。 相似文献
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In this study, the influence of press cycle time and resin content (RC) on some of the physical and mechanical properties of single-layer particleboard manufactured from the low-quality raw materials were determined. Eucalyptus (Eucalyptus camaldulensis), mesquite (Prosopis juliflora), saltcedar (Tamarix stricta) and date palm (Phoenix dactylifera) wood, which is underutilized invasive species in southern parts of Iran, were used as alternative raw materials for particleboard manufacturing. Variable factors were as resin content (9, 10 and 11%) and press time (PT) (4, 5 and 6 min). Other parameters such as type of resin (UF), hardener content (2%), type of hardener (NH4Cl), press-closing time (4.5 mm/s), board density (0.75 g/cm3), press pressure (30 kg/m2) and press temperature (160 °C) were held constant. The experimental panels were tested for their mechanical strength including modulus of elasticity (MOE), modulus of rupture (MOR), internal bonding (IB) and physical stability properties (thickness swelling) according to the procedures defined by European Union (EN) Standard. Overall results showed that most panels made from above-mentioned materials exceed the EN Standards for IB, MOE and MOR. The mechanical properties of particleboard were improved as the resin content increased from 9 to 11%. The results indicated that the polymerization of resin and wood is better at 11% resin content and 5 min of press time. However, thickness-swelling (TS) values were higher (poor) than requirements. Panels made of mesquite, saltcedar and date palm with a resin content of 11% and pressed for 5 min is adequate for general uses while eucalyptus with a resin content of 11% and pressed for 6 min is suitable for interior decoration. 相似文献
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缓/控释肥料对果蔗产量及氮素利用率的影响 总被引：1，自引：0，他引：1
为改善果蔗施肥技术、提高果蔗种植的经济效益和环境效益,开展了国产控释配方肥、脲醛缓释复合肥和进口复合肥在果蔗上应用的大田试验。结果表明,果蔗栽培中施用缓/控释配方肥料较施用进口复合肥的产量和总生物量分别提高了1.8%~5.7%和5.7%~15.5%。与进口复合肥相比,缓/控释配方肥料成本更低,施用控释配方肥和脲醛复合肥每公顷增收11 144~17 147元和20 835~23 037元。此外,施用控释配方肥可以显著提高果蔗的NAE、NPF及NUE,提高果蔗氮肥利用效率。果蔗栽培过程中合理地施用缓/控释配方肥料能促进果蔗增产、增收、提高肥料利用率。缓/控释配方肥料可以取代进口复合肥为果蔗生长提供养分,实现轻简施肥。 相似文献
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Ujjal KaurHarinder Singh Oberoi Vinod Kumar BhargavRatna Sharma-Shivappa Sandeep Singh Dhaliwal 《Industrial Crops and Products》2012,37(1):219-226
In the present study, milled cotton stalks were subjected to alkali pretreatment with NaOH at 1-4% (w/v) concentrations at 121 °C for time ranging from 30 to 90 min. Ozone pretreatment was performed by passing 45 mg/L of ozone gas over 2 mm cotton stalks for 150 min at a flow rate of 0.37 L/min. The residual biomass from 4% alkali pretreatment for 60 min showed 46.6% lignin degradation accompanied by 83.2% increase in glucan content, compared with the untreated biomass. Hydrolysis of 4% alkali-treated and ozone-treated cotton stalks was conducted using enzyme combination of 20 filter paper cellulase units/gram dried substrate (FPU/g-ds), 45 IU/g-ds β-glucosidase and 15 IU/g-ds pectinase. Enzymatic hydrolysis of alkali-treated and ozone-treated biomass after 48 h resulted in 42.29 g/L glucose, 6.82 g/L xylose and 24.13 g/L glucose, 8.3 g/L xylose, respectively. About 99% of glucose was consumed in 24 h by Pichia kudriavzevii HOP-1 cells resulting in 19.82 g/L of ethanol from alkali-treated cotton stalks and 10.96 g/L of ethanol from ozone-treated cotton stalks. Simultaneous saccharification and fermentation of the alkali-treated cotton stalks after 12-h pre-hydrolysis resulted in ethanol concentration, ethanol yield on dry biomass basis and ethanol productivity of 19.48 g/L, 0.21 g/g and 0.41 g/L/h, respectively which holds promise for further scale-up studies. To the best of our knowledge, this is the first study employing SSF for ethanol production from cotton stalks. 相似文献
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茄子种质资源苗期耐涝性鉴定 总被引：1，自引：0，他引：1
本实验旨在找到鉴定茄子耐涝性强弱的方法,并筛选出耐涝性较强的种质资源,为今后进行茄子耐涝机理的研究以及耐涝新品种的选育奠定基础。在涝害胁迫后利用综合恢复指数评价了263份种植资源的耐涝性。恢复指数结果表明,供试品种圆茄子、许昌紫茄、观赏茄、紫长茄、墨茄王、荷包茄、雎县紫茄等94个材料耐涝性较强;而野茄子-3、墨玉长茄、引茄1号、早白茄、汉宝3号、茄26、安阳紫冠等34个材料耐涝性较差。茄子种质资源苗期耐涝性强弱的鉴定对茄子生产具有重要的参考意义。 相似文献
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为筛选花生秸秆饲用性评价指标和饲用价值高的种质，以40份生物量较大的品种（系）为材料，利用NIRS方法分别检测收获后花生茎秆、叶片和种子部位的蛋白质、钙、磷、中性洗涤纤维、酸性洗涤纤维、干物质、酸性洗涤木质素和体外干物质消化率等指标。结果表明，叶片中的蛋白质含量较茎秆高5%以上，营养价值较高；茎秆、叶片、种子部位对钙和磷的吸收均具有协同特征；茎秆、叶片中的钙、磷含量分别与蛋白质含量呈显著或极显著负相关，种子中的钙、磷含量均与蛋白质含量极显著正相关。秸秆饲用性评价分析表明，利用主成分分析共提取到5个主成分，代表茎秆、叶片检测指标91.12%的信息，可用于花生品种（系）秸秆饲用性的综合评价；根据各品种（系）的综合得分D值筛选出10份饲用价值较高的品种（系）；构建了花生秸秆饲用性评价的回归方程，D=0.014X1+0.012X2-0.003X5+0.009X7-0.023X8+0.009X10+0.011X16-1.582（R2=0.994，F=764.329，P<0.01），该方程的估计精度达88.0%以上，方程中茎秆的蛋白质、灰分、中性洗涤纤维、植物干物质、酸性洗涤木质素、叶片的蛋白质和干物质共7个指标可作为花生秸秆饲用性综合评价指标。 相似文献
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咖啡碱-辅酶A-O-甲基转移酶（caffeoyl-CoA-O methyltransferase, CCoAOMT）是木质素合成途径的关键酶,但其在逆境胁迫中也发挥重要作用。根据茄子基因组数据设计引物克隆了CCoAOMT,命名为SmCCoAOMT,其最大阅读框为564 bp,编码187个氨基酸,相对分子质量为20.95 ku。生物信息学分析发现SmCCoAOMT与其他植物的CCoAOMT序列同源性高达90.67%,同时具有CCoAOMT的全部保守序列。对其在不同果皮颜色茄子品种及35 ℃高温下果实不同发育时期的表达进行了qRT-PCR分析,结果表明SmCCoAOMT在果皮颜色深的茄子品种中的相对表达量高于在果皮颜色浅的品种中的表达量,说明SmCCoAOMT的表达量与茄子果色呈正相关;与常温对照相比,在花后10和20 d时,高温胁迫下SmCCoAOMT的表达量都显著下降,尤其是在花后10 d时,表达量仅为对照的9.23%,说明SmCCoAOMT表达量显著下调可能是导致果皮颜色变浅的原因之一。结果推测SmCCoAOMT在高温胁迫下茄子果皮颜色变浅的过程中起正调控作用。 相似文献
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Ethanol production from agro-waste provides an alternative energy-production system. Statistical experimental designs were used for optimization of critical nutrients and process variables for ethanol production. The critical nutrients and process variables were initially selected according to a Placket-Burman (PB) design. Selected factors (inoculum level 1-5%, pH 4.5-7, temperature 25-35 °C and urea concentration 0.25-0.75 g/L) were optimized by response surface methodology (RSM) based on a three-level four-factor Box-Behnken design (BBD). Under optimum conditions of inoculum level 3%, pH 5.75, temperature 30 °C and urea concentration 0.50 g/L maximum ethanol production obtained 13.2 g/L from microwave alkali pretreated rice straw with ethanol productivity 0.33 g/L/h. Under optimum conditions ethanol production studied at fermenter level and obtained ethanol concentration 19.2 g/L, ethanol productivity 0.53 g/L/h and ethanol yield to consumed sugar 0.50 g/g. These results indicated that ethanol production can be enhanced by optimization of nutritional and process variables. 相似文献
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Perennial ryegrass cv. S23 was preserved by fermentation (C), or with the addition of 8.7 1 formalin (35% w/w formaldehyde) per t fresh herbage (F) or of 9.0 1 equal mixture (by vol.) of formalin and formic acid (85% w/w solution) per t fresh herbage (FF). These three silages comprised the treatments in a three-period, crossover design in which urea (u) was given at the rate of 20 g per kg dietary DM to half the animals. Twelve calves were allocated to the treatment sequences when they were approximately 12 weeks of age from within groups which had previously received diets with or without urea. Calves ate significantly (P< 0.001) less of silages F or FF than of silage C when each was offered alone, but when urea was given, intakes of silages F and FF were significantly (P < 0.001) increased such that the intakes of all three silages with urea were similar (23.6, 19.6, 19.3, 24.2, 24.2, 24.7 ± 0.51 g DM per kg LW for C, F, FF, Cu, Fu and FFu, respectively). Significantly (P<0.01) more of the DM in silage C was digested than in F or FF and the addition of urea significantly (P<0.05) increased the digestibility of DM from silage FF only (73.8, 71.3, 69.8, 74.6, 70.7, 72.5 ± 0.72% for C, F, FF, Cu, Fu and FFu, respectively). When the silages were given alone, calves spent longer eating and ruminating per kg DM ingested with F or FF than with C. The time spent on F and FF was significantly (P<0.01) reduced by the addition of urea (303, 388, 411, 297, 299, 290 ± 18.9 min per kg DM ingested for C, F, FF, Cu and Fu and FFu, respectively). The results presented suggest that urea partially alleviated the reduction in voluntary intake by calves given herbage preserved using formalin, but the mode of action was not clear. 相似文献