影响纤维素酶水解木屑的若干因子的研究

木霉201,79、SA3和1096产生的纤维素酶对天然木屑的水解能力都极其低微,但当木屑氮过适当的预处理以后,酶的永解能力明显地提高。X₂-85菌纤维素酶在45℃保温24h,酶活损失15％左右。用三种底物考察酶用量与酶解率之间的关系：酶浓度增加100％,木纸浆的酶解增长率为120％,脱脂棉的酶解增长率为31％,酸处理木粉的酶解增长率为2％。差别很悬殊,说明提高酶解率的主要途径,是把对酶亲和力小的木屑转变为对酶亲和力大的底物。     

熟地多糖活性炭脱色工艺的研究

本研究旨在探讨活性炭对熟地多糖提取液脱色的工艺条件。在单因素试验基础上,采用正交试验,以多糖脱色率(%)和多糖剩余率(%)为指标,用紫外-可见分光光度法测定,确定了熟地多糖活性炭脱色的最优工艺的参数。结果发现:活性炭添加量对脱色效果的影响最大,其次为温度,再次为时间。最佳脱色条件为脱色温度60℃,活性碳添加量5%,吸附时间30 min,在此条件下,脱色率为98.20%,多糖剩余率为84.89%。从而表明活性炭对熟地多糖脱色工艺可行,简便,有效。     

板蓝根多糖活性炭脱色工艺及抗氧化活性研究

采用活性炭对板蓝根多糖进行了脱色研究。在单因素实验的基础上进行了正交实验,得到活性炭脱色的最佳工艺条件为:70℃下调节p H为7.0,添加体积分数为1.0%的活性炭,搅拌80 min,脱色率为92.97%、多糖保留率为92.45%。采用DPPH孤电子配对法测定DPPH自由基的清除作用;采用邻苯三酚自氧化法检测超氧阴离子自由基的清除作用。实验结果表明,板蓝根多糖具有一定的清除自由基的能力,但脱色后的多糖清除自由基的能力降低。     

啤酒废酵母制备碱不溶性葡聚糖

以啤酒废酵母为原料,采用碱提法确定了碱不溶性葡聚糖的制备条件,使用1.0 mol.L-1的NaOH溶液,以固液比为1:5进行提取,45℃处理6 h。此条件下碱不溶性葡聚糖得率可达10.94%,其多糖质量分数可达91.57%。红外光谱分析显示产品为β-(1-3)键的葡聚糖,其中不含甘露聚糖。     

板蓝根多糖活性炭脱色工艺及抗氧化活性研究北大核心CSCD

采用活性炭对板蓝根多糖进行了脱色研究。在单因素实验的基础上进行了正交实验,得到活性炭脱色的最佳工艺条件为:70℃下调节p H为7.0,添加体积分数为1.0%的活性炭,搅拌80 min,脱色率为92.97%、多糖保留率为92.45%。采用DPPH孤电子配对法测定DPPH自由基的清除作用;采用邻苯三酚自氧化法检测超氧阴离子自由基的清除作用。实验结果表明,板蓝根多糖具有一定的清除自由基的能力,但脱色后的多糖清除自由基的能力降低。     

固态发酵预处理木屑对其制备成型燃料的影响

为了解决生物质成型产业存在的成型燃料密度低、强度低、抗吸水能力弱、不耐存储等问题,采用黄孢原毛平革菌Phanerochaete chrysosporium BKMF21767对黧蒴栲木屑(Castanopsis fissa Rehd.et Wils)进行固态发酵预处理,固态发酵木屑在含水率15%和最大压强98 MPa的条件下制备成型燃料。以成型能耗(挤压和推动能耗)、成型燃料密度、Meyer强度和吸水性等表征发酵时间对黧蒴栲木屑成型行为及成型燃料性能的影响。结果表明:与由新鲜黧蒴栲木屑制备的成型燃料相比,经固态发酵的黧蒴栲木屑成型燃料的燃烧热值几乎不变,虽然在成型过程中的挤压能耗最高升高6.98%,但推动能耗最高可降低32.19%。同时,固态发酵预处理能够提高成型燃料的密度、Meyer强度和抗吸水能力,有利于成型燃料在长时间储运中保持品质,其中由固态发酵48 d左右的木屑制备的成型燃料品质最佳。     

生物活性炭的研究现状

本文总结了生物活性炭(BAC)技术在废水及饮用水处理领域的应用。臭氧(O3)常与生物活性炭联合应用于饮用水源水的处理,并能有效去除水中天然有机物及微量有害物质。生物活性炭工艺将在饮用水处理中有更广阔的应用空间。     

三种速生固氮树木屑栽培猴头菌的研究

以固氨树种银合欢、南洋楹、大叶相思的木屑为主料,添加棉籽壳等辅料培养猴头菌,以栲树木屑为主料作对照。结果表明,以三种固氨树木屑栽培的猴头菌,菌丝粗壮,均匀,日长速快于对照,增长5.4%~16.2%,而且出菇快,朵形大,产量比对照增加6.0~13.9%。添加南洋楹基质的菌丝长速最快,其次为添加银合欢基质。产量则以添加银合欢基质的最高,添加大叶相思的次之。     

工业废羊毛酸解工艺条件选择

毛发蛋白盐酸水解提取胱氨酸时 ,温度、毛酸比、时间等因素影响到毛发蛋白的水解率和产品胱氨酸的总收率。通过正交试验法 ,进行了废羊毛酸解工艺参数的试验研究 ,确定了最佳酸解工艺参数为 :温度 1 0 5℃ ,毛酸比(W/V) 1∶1 .7,连续水解时间 7.0h。     

水解工业废羊毛提取胱氨酸的工艺参数的改进

利用人发、猪毛水解提取胱氨酸的生产线,以工业废羊毛为原料水解提取胱氨酸,给出了改进后的工艺参数。试验证明：成品收率提高到４．９％,成品合格率１００％。     

利用水蒸气活化稻壳生产活性炭的研究

研究了水蒸气法活化制备稻壳活性炭的工艺条件,探讨了炭化温度、活化温度、活化时间和水蒸气用量对活化效果的影响。结果表明最佳工艺条件为:炭化温度450℃、活化温度900℃、活化时间90 min和水蒸气用量为炭化料的1.5倍,制备的活性炭碘值844 mg/g,亚甲基蓝吸附值138 mL/g。这些指标与木质活性炭相当。且投资少,能耗低,具有良好的社会效益与经济效益。     

The Temporal Distribution and Carbon Storage of Large Oak Wood in Streams and Floodplain Deposits

We used tree-ring dating and ¹⁴C dating to document the temporal distribution and carbon storage of oak (Quercus spp.) wood in trees recruited and buried by streams and floodplains in northern Missouri, USA. Frequency distributions indicated that oak wood has been accumulating in Midwest streams continually since at least the late Pleistocene, about 14,000 calibrated radiocarbon years before present (cal. BP). The median residence time of an oak bole in the study streams was 3,515 years (n = 200). More than 30% of sampled oak wood entered the floodplain sediments and stream waters within the last 1,000 years, though very few samples dated to the last 150 years. Temporal variability in the record of oak recruitment to streams suggests a potentially strong influence from shifts in climate and fluvial processes, although other possible influences are addressed. Recent human impacts on streams have altered the dynamics of oak input and sequestered carbon with unknown long-term consequences. The long duration of carbon storage (mean age = 1,960 years) in this waterlogged environment appears to be strongly limited by decreasing wood density resulting from reductions in cell wall thickness. Lack of evidence of biotic degradation may imply that wood loss is largely due to abiotic hydrolyses. These findings document a continuous and long-term form of carbon storage that is sensitive to changes in climate and anthropogenic alteration of fluvial processes.     

由人发制备胱氨酸的工艺研究

实验对胱氨酸的生产流程作了进一步的探讨 ,讨论了原料的用量、酸度、水解时间、水解温度及收得率的最佳条件 ,在提高生产工艺的同时 ,降低生产成本。     

Effect of Acid Hydrolysis of Oak Wood on Its Aroma-Forming Complex

The effect of acid hydrolysis of English oak (Quercus robur L.) wood on its aroma-forming complex was studied. The contents of methanol, acetic and crotonic acids, and furfural increased considerably in the samples treated with hydrochloric acid. In the composition of minor compounds, aromatic hydrocarbons were synthesized de novo, whereas the contents of volatile phenols, such as vanillin, lilac aldehyde, and coniferaldehyde decreased; relative content of guaiacol and syringol elevated; and acetovanillon and propiovanillon were formed as well as products of degradation of hexoses—levoglucosenone, 1,4:3,6-dianhydroglucose, maltol, and 1,6-dianhydroglucopyran.     

黑龙江省东宁县山区蜱类的生态调查

我国东北地区有的蜱种已证实是传播森林脑炎、北亚蜱传斑疹伤寒的媒介。近年来,国内文献又报导了从东北牡丹江林区发现了莱姆病(Lyme Disease)病人,病人都有被婢咬史,并从全沟硬蜱(Ixodes persulcatus)的中     

Effects of Heat Pretreatment During Impregnation on the Preparation of Activated Carbon from Chinese Fir Wood by Phosphoric Acid Activation

Activated carbons were prepared from Chinese fir wood by phosphoric acid activation. The effects of heat pretreatment from 80 to 180 °C during impregnation on the properties of fir wood and its activated carbons were discussed. The crystallinity index and surface chemistry of the pretreated fir wood were characterized by X-ray diffraction and Fourier transform infrared spectroscopy (FT-IR). The porous texture of activated carbons was investigated by N₂ adsorption–desorption isotherms. The results showed that with increasing pretreatment temperature, the crystallinity of the pretreated samples decreased, which gave rise to a significant development of pores, especially micropores as high as 97.2 %. FT-IR results revealed that the carbonyl-containing and phosphorus-containing groups of the pretreated samples increased with increasing pretreatment temperature. For a temperature of 140 °C, the specific surface area, the total pore volume, and the micropore volume reached a maximum of 1603.0 m²/g, 0.792 cm³/g, and 0.770 cm³/g, respectively. However, a higher pretreatment temperature was not beneficial for activation. Thus, heat pretreatment during impregnation can be regarded as an excellent method for manufacturing phosphoric acid-activated carbon with a high micropore volume.     

Nutrients and Trace Elements Content of Wood Decay Fungi Isolated from Oak (Quercus ilex)

The presence of chemical elements and the differences in their concentration in the fruiting bodies of wood decay fungi may reflect their activity either as saprobes or parasites and the intimate physiological relation with the substrate from which they extract their nutrients. In order to test this hypothesis, we carried out a systematic sampling of eight species of wood decay fungi on oak (Quercus ilex). The data show that the concentration of some elements exhibits a very wide range of values for the species tested, which could mean that the relative content of some elements may provide clues about the nature of the substrate and, moreover, about the nutritional physiology. The comparison between the foliar analysis (FA) and the elemental content of fungi may shed light on the specific physiological behaviour of the species. Potassium is an element accumulated in fungal biomass in higher quantities than in the FA. By contrast, calcium appears in foliar analysis in much higher quantities than in fungal fruiting bodies' biomass. Concerning this element, we have also found profound differences between the two species phylogenetic groups and lifestyle. Of all elements measured, we believe that the relative accumulation of K and Ca may be related to the close connection between fungi and the substrate on which they live and may also explain their physiological role as saprobes or parasites. When the lifestyle and the systematic position of the different species sampled were compared, differences also emerged in the content of Na and Ca.     

利用毛发水解提取胱氨酸后的废液研制氨基酸复合肥料

利用胱氨酸废液中游离氨基酸为主要成份研制氨基酸肥料,既解决了废液排放问题,又开辟了新的肥料来源。本文详尽叙述这一研制的工艺原则流程,强调添加剂在这一流程中的作用,并对氨基酸肥料的肥效进行了试验研究。     

氨基酸混合液脱色条件的比较选择

以四种粉末状活性炭作为脱色剂,对猪血粉水解液进行脱色比较,结果表明：江西产的４号粉末状活性炭脱色效果最佳。本文还对４号脱色炭的脱色条件进行了摸索研究。     

鸭毛梗制备复合氨基酸工艺条件的研究

采用正交试验方法 ,研究了鸭毛梗水解制备复合氨基酸的工艺条件 ,结果表明 :温度 /压力是影响氨基酸转化率最主要的因素。鸭毛梗水解制备的复合氨基酸转化率盐酸法最高 (82 .36 % ) ,氢氧化钠法最低 (5 8.4 6 % ) ,硫酸法与盐酸法接近(79.4 4 % )。硫酸法产率较高 ,操作方便 ,环境污染和设备腐蚀均小 ,适合大量生产 ,确定为水解制备复合氨基酸介质 ,其最佳工艺条件为 :水解时间 8.0h ,硫酸浓度 3.0mol·L-1,水解温度 12 5℃。氨基酸分析表明 ,水解液中均含有 18种以上氨基酸。