Adsorption of uranium from sulfate leach liquor using rice straw impregnated with chlorophenyl hydrazinyl pyrazoloquinazolinon

The impregnation of rice straw with 2-amino-3-(2-(4-chlorophenyl)hydrazinyl)-8,8-dimethyl-8,9-dihydropyrazolo[1,5-a]quinazolin-6(7H)-one (CPHPQ) has been used for the recovery of uranium from sulfate leach liquor. The uranium adsorption and elution of solvent impregnated mercerized rice straw (SIMRS) were carried out using a batch technique. The uranium adsorption controlling factors include pH, initial uranium concentration, contact time, S/L ratio, and temperature. Thermodynamic characteristics showed that the adsorption process is exothermic with enthalpy change ΔH = ?152.1 kJ/mol. The kinetics data fit well with a pseudo-second-order model. The equilibrium data fit well with the Langmuir isotherm. Uranium cake was obtained from the eluate solution using hydrogen peroxide as UO₄.2H₂O precipitate.     

不同增韧剂对PLA/小麦秸秆复合材料性能的影响

以茂金属聚乙烯（mPE）及乙烯辛烯共聚物（POE）为增韧剂,通过模压成型的方法制备了聚乳酸(PLA) /小麦秸秆复合材料,研究了增韧剂种类、含量对PLA/小麦秸秆复合材料的力学性能及吸水性能的影响,同时对所得复合材料进行了X射线衍射分析以及红外分析。结果表明,随着mPE/POE含量的增加,复合材料的洛氏硬度和拉伸、弯曲、冲击强度均呈现先增大后减小的趋势;当mPE和POE含量均为5 %~10 %（质量分数,下同）时,复合材料的各项性能较好。     

土壤深耕与秸秆还田对土壤物理性状及烟叶产质量的影响

为探明江西典型植烟区适宜耕作方式,改善烟区土壤理化性质,在稻烟轮作区开展田间试验研究深耕对土壤物理性状、烤烟生长与烟叶产质量的影响。结果表明,在5~10 cm土层,秸秆还田显著降低了土壤容重、增加了土壤总孔隙度、毛管孔隙和通气孔隙;在20~25 cm土层,深耕和秸秆还田均显著降低了土壤容重,提高了土壤通气孔隙。深耕显著降低了土壤的贯穿阻力,秸秆还田通过增加5~10 cm土层≥2 mm团聚体的含量进而增加了土壤大团聚体的比例。深耕和秸秆还田均能提高烟株根茎叶的干物质量、促进其对氮磷钾的吸收,以深耕处理与深耕+秸秆还田处理效果更显著。深耕和秸秆还田显著提高了烟叶产量、产值和烟叶评吸总分。利用圆盘犁深耕土壤结合水稻秸秆还田是改良植烟土壤、提高烟叶产质量的可行技术措施。     

含油浮渣与高粱秆协同制备活性炭的研究

以含油浮渣和高粱秆为原料协同制备活性炭,制备过程分为低温炭化制备炭前体和高温活化制备活性炭两个阶段。炭前体的制备条件为含油浮渣与高粱秆质量比3∶1,炭化温度450℃,炭化时间2h。制备的炭前体表面具有一些孔道,其浸出液重金属含量不超标,使用过程中不会造成重金属污染。利用正交实验和单因素实验对炭前体高温活化制备活性炭的影响因素进行了深入研究,确定的最佳活化条件为以KOH为活化剂,炭前体与KOH质量比1∶4,活化温度800℃,升温速度15℃/min,活化保温时间1h。制备的活性炭表面分布着众多孔隙,大孔深处可见若干层小孔,孔径分布以微孔和介孔为主。比表面积、孔隙体积、平均孔径和碘吸附值分别达到1 648.74m~2/g、1.84cm~3/g、1.76nm和957.82mg/g,均超过了市售的木质商品活性炭。     

Hybrid high-porosity rice straw infused with BiVO4 nanoparticles for efficient 2-chlorophenol degradation

In this work, the coupling of BiVO₄ nanoparticles with a highly porous material derived from rice straw (BiVO₄/RS composites) and the photocatalytic degradation of 2-chlorophenol (2-CP) in an aqueous solution was studied. The results indicated that BiVO₄/RS composites possessed a monoclinic structure. The morphologies of BiVO₄/RS composites consisted of spherical shapes of BiVO₄ particles coated on the RS adsorbent. The specific surface area of BiVO₄ increased from 1.9024 to 31.1153 m²/g after coating with RS adsorbent. A shift occurred in adsorption edge from 510 to 525 nm, corresponding to a reduction in band gap energy from 2.43 to 2.35 eV. The change in the optical adsorption edge and band gap of BiVO₄/RS composites may simultaneously result to the duplication of a structure caused by silicon species in rice straw, which was expected to be self-doped into the BiVO₄ crystal lattice during synthesis. The photocatalytic performance of 2-chlorophenol under visible irradiation clearly showed that BiVO₄/RS composites displayed the highest photocatalytic activities in comparison with other pure samples, which were 2 times higher than that of BiVO₄.     

Physicochemical characterization of alkali treated fractions from corncob and wheat straw and the production of nanofibres

Raw cereal materials (CM) (corncob and wheat straw) were alkaline treated to produce insoluble fibrous residues (IF) and soluble fibrous residues (SF). Physicochemical properties of each portion were evaluated. CM contained high amounts of dietary fibre (DF; 49.87–68.65%), while IF and SF mainly contained insoluble and soluble DF, respectively. CM and IF contained essential minerals (calcium, copper, iron, potassium, magnesium and phosphorus) while SF was free from heavy metals. CM and IF also exhibited DPPH radical scavenging ability (54.25 to 77.24%), good emulsification ability (3.73–5.29%) and emulsion stability (75.00–86.94%), mineral binding capacity (calcium, copper, iron, zinc), water holding capacity (2.82–6.01 g_water/g_sample) and oil holding capacity (2.61–4.00 g_oil/g_sample). IF and SF could be potentially developed into new functional food materials. The successful production of SF into nanofibres by electrospinning showed potential applications as delivery systems for bioactive and functional ingredients.     

氢氧化镁协同麦草留硅蒸煮工艺初探

研究Mg(OH)2对麦草NaOH-AQ制浆和黑液的性质的影响,评价Mg(OH)2的留硅效果。试验结果表明:Al2O3用量2%,Mg(OH)2用量为1%时,细浆得率39.56%,浆中SiO2含量2.70%,黑液SiO2含量为0.0683%,与Al2O3留硅相比得率低2.46%,KMnO4值低1.15,浆中SiO2高1.88%。     

秸秆纤维素降解菌的分离筛选、复合菌系构建及产酶条件优化

该研究采用刚果红染色法和滤纸条崩解法从山西老陈醋源中分离筛选纤维素降解菌,通过形态观察及分子生物学技术对其进行菌种鉴定。以滤纸酶活性为筛选指标构建复合菌系,采用单因素试验及响应面试验对其产酶发酵条件进行优化,并评价其对不同秸秆的降解效果。结果表明,筛选出3株纤维素降解菌,编号为J1、J2和J3,分别被鉴定为灿烂类芽胞杆菌（Paenibacillus lautus）、千叶类芽胞杆菌（Paenibacillus chibensis）和窖泥类芽胞杆菌（Paenibacillus vini）。3株菌等比例复配得到最佳复合菌系D,其最优产酶发酵条件为初始pH 7.4,接种量9%,发酵温度40℃。在此优化条件下,滤纸酶活性达到35.10 U/m L,是优化前的1.6倍。复合菌系D对不同秸秆均具有较好的降解效果,且对小麦秸秆的降解率最高,达27.63%。     

麦草浆绿液预苛化法及CO2法除硅研究

麦草浆绿液硅含量高,影响碱回收工序的顺利进行,对白泥的回收利用也有不利影响。本文研究了绿液预苛化法除硅和CO2法除硅的效果。结果表明：预苛化法除硅的除硅率为60％～80%,CO2法除硅的除硅率可达90％以上。     

麦草、芦苇混合烧碱蒽醌法制浆工艺技术

为了解决连续蒸煮系统原料单一问题,重点对麦草、芦苇5：5混合蒸煮制浆工艺进行实验。通过对生产过程控制数据检测和蒸煮工艺技术参数的合理调整确定,使得草、苇混合蒸煮制浆的各项实际检测数据符合拟定的工艺技术要求,且浆料的滤水性能得到改善,在后续草、苇混合蒸煮过程中,均无异常波动,漂白浆各项工艺标准符合下道工序的要求。