热烟气气氛下生物质在流化床反应器中快速热解制取生物油

在对操作流化速度进行冷态实验以及流化床温度稳定性进行测试的基础上,研制了新型流化床反应器,并使用玉米秸秆为原料,探究了热烟气气氛下快速热解制取生物油的最佳反应温度以及床料。在最佳热解条件下,对糠醛废弃物、木糖废弃物以及海藻进行了实验研究,得到了各产物产率,并对得到的生物油进行了物理特性分析。结果显示,在最佳操作流速下,当温度为500 ℃时使用白云石为床料可以获得最大生物油产率。4种原料中玉米秸秆的生物油产率最高,达到42.3 wt%。在最佳热解条件下获得了4种物料不同含量的重油和轻质油,其中重油的物理特性差别很小,重油的热值比轻质油的热值高很多。不可冷凝气的高位热值是6.5?8.5 MJ/m3,因此不可冷凝气体可以作为一种燃料气被加以利用。     

热烟气气氛下生物质在流化床反应器中快速热解制取生物油（英文）

在对操作流化速度进行冷态实验以及流化床温度稳定性进行测试的基础上,研制了新型流化床反应器,并使用玉米秸秆为原料,探究了热烟气气氛下快速热解制取生物油的最佳反应温度以及床料。在最佳热解条件下,对糠醛废弃物、木糖废弃物以及海藻进行了实验研究,得到了各产物产率,并对得到的生物油进行了物理特性分析。结果显示,在最佳操作流速下,当温度为500℃时使用白云石为床料可以获得最大生物油产率。4种原料中玉米秸秆的生物油产率最高,达到42.3 wt%。在最佳热解条件下获得了4种物料不同含量的重油和轻质油,其中重油的物理特性差别很小,重油的热值比轻质油的热值高很多。不可冷凝气的高位热值是6.5-8.5 MJ/m3,因此不可冷凝气体可以作为一种燃料气被加以利用。     

巢湖蓝藻与农业废弃物共热解制取生物质油研究

采用蔗渣、玉米秸秆和棉花秸秆3种废弃物与蓝藻进行混合共热解试验,考察废弃物的加入对蓝藻热解液体产率及组分的影响。结果表明:添加3种废弃物均使共热解液体产率呈下降趋势。当蓝藻与废弃物以1∶1混合共热解时,以蓝藻和玉米秸秆共热解液体产率最高,为61.8%,且除苯酚类以外,液体产物组分与单一蓝藻热解产物组分相近,含氮化合物含量明显降低,相对含量由18.49%降至8.15%。与其它2种废弃物相比,蓝藻与玉米秸秆在适当比例下的共热解有利于改善热解油品质。     

玉米芯热解制备多孔炭材料的研究进展

玉米芯作为典型的农业废弃物,是制备生物炭材料的优质原料之一。文章以玉米芯为研究对象,综述了玉米芯热解制备生物炭的研究进展,并对热解制备的玉米芯基生物炭理化特性的影响因素进行了分析,主要包括热解制备过程中的热解方式、热解温度、升温速率及改性方法等因素。研究表明,不同制备条件和改性方法对玉米芯生物炭的理化性质有着显著的影响。文章还对玉米芯生物炭的制备进行了展望,以期为玉米芯生物炭的规模化制备和利用提供借鉴与指导。     

松木热解焦油的炭催化二次裂解特性

利用两段固定床反应器研究了木炭对松木热解焦油的催化二次裂解特性.焦油通过700 ℃木炭层与通过相同温度的空管相比,焦油产率(包括水分)从26.7% 降低至16.4 %(wt.), CH4 产率从3.7 降低至2.8 mmol/g 干基生物质,而CO 产率基本不变,H2 和CO2 的产率则分别从3.6、2.9 提高至11.8、6.6 mmol/g 干基生物质,表明木炭具有明显促进焦油二次裂解及甲烷分解的作用.并利用气质联用(GC-MS)和火焰离子检测气相色谱(FID-GC)对液体产物进行定性和定量分析,观察到下段松木热解焦油经过600℃的木炭层后,其组成中糖、醛、酮以及愈创木酚类等含氧化合物发生剧烈分解,液相成分主要为酚类;温度越高,芳香化程度越大.     

黄芩甙提取工艺研究

本文研究了纤维素酶在黄芩甙提取工艺上的应用。纤维素酶的比活力为1500个活力单位,酶解温度为50℃、pH值为5.0、酶解时间为18 h、煎煮时间为40 min。实验结果表明:加酶提取黄芩甙比不加酶提取的产率提高16.3%,产物中黄芩甙的纯度有明显的提高。     

玉米芯综合利用研究进展

玉米芯主要由纤维素、半纤维素和木质素构成,便于收集、易加工处理,已被广泛应用于生产食品、饲料和化工产品中,但目前仍存在原料利用率低、能耗大、成本高等问题。本文对农业废弃物玉米芯工业化综合利用相关的工艺进行探讨,通过论述玉米芯中半纤维素、纤维素和木质素三大组分的高值化利用方式,阐述了玉米芯综合利用的产业化途径。     

内切酶法制取菊苣低聚果糖工艺条件的研究

目的:利用毕赤嗜甲醇酵母表达的重组黑曲霉菊粉内切酶,从菊苣菊粉中制取低聚果糖。方法:用重组黑曲霉菊粉内切酶酶解水提菊粉,用薄层色谱、离子色谱分析酶解产物,研究酶解条件,分析产物组成。结果与结论:菊粉浓度为20～160g/L、酶浓度为12U/g菊粉时,低聚果糖的最大产率逐渐升高然后下降;在接近最大溶解度200g/L时,菊粉寡糖最大产率为62.0%,最大产率与酶的用量无关,但提高酶的浓度可以缩短达到最大产率的时间。pH5.5、50℃、菊粉浓度为40g/L、酶用量为12U/g菊粉时,可达到最大产率64.6%;酶解的产物主要为GF2到GF10的菊粉寡糖。     

布迪椰子不同器官热值的季节变化研究

对布迪椰子的幼叶、成熟叶、叶柄和根在不同季节的干重热值、去灰分热值和灰分含量进行了研究,结果表明:干重热值四个季节的平均值为成熟叶(20.65kJg-1)>幼叶(19.84kJg-1)>根(19.55kJg-1)>叶柄(18.77kJg-1),秋季的干重热值明显高于其它三个季节的干重热值,冬季的干重热值最低,去灰分热值与干重热值的变化趋势基本相同。灰分含量四个季节的平均值为根(5.14%)>叶柄(4.33%)>幼叶(4.21%)>成熟叶(3.97%)。成熟叶的灰分含量一直维持在比较低的水平,而幼叶的在秋季明显下降,在冬季明显上升,幼叶灰分含量的季节变化趋势与成熟叶的相同,叶柄灰分含量在冬季明显低于根部。布迪椰子这种不同器官在不同季节的热值和灰分的变化规律显示其具有较强的耐寒适应性。     

H_2O_2预处理结合微生物发酵提取玉米芯木聚糖的工艺研究

为提高微生物发酵玉米芯提取木聚糖的效率,本研究采用H2O2预处理结合微生物发酵的方法提取玉米芯中的木聚糖,并通过扫描电镜(SEM)从微观结构初步探讨了H2O2预处理提高微生物发酵提取玉米芯木聚糖的原因。其结果表明:利用4%H2O2预处理玉米芯1小时,木聚糖含量可达40. 21±0. 21 mg/g,较未处理组玉米芯中木聚糖含量提高了87. 72%;4%H2O2预处理结合微生物发酵玉米芯,可显著提高木聚糖得率,其含量可达52. 72 mg/g,较未经H2O2预处理组提高了186. 67%;进一步利用响应面法优化微生物发酵经H2O2预处理玉米芯提取木聚糖的工艺,得到了发酵最佳培养基组成为含水量50%、尿素添加量0. 25%、葡萄糖添加量0. 75%,此条件下木聚糖含量达70. 84 mg/g,较未发酵提高了249. 82%;SEM图像显示H2O2预处理使得玉米芯结构变得疏松,微生物发酵结合H2O2预处理后的玉米芯出现较大孔洞,结构变得更为疏松。因此,H2O2预处理可改善玉米芯结构,促进微生物发酵,提高玉米芯木聚糖的提取效率,为玉米芯木聚糖的高效开发利用提供了参考。     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

鸡传染性法氏囊病病毒研究进展

传染性法氏囊病(Infection bursal disease, IBD)是由鸡传染性法氏囊病毒(Infectious bursal disease virus, IBDV)引起的鸡和火鸡的一种高度接触性传染病,给世界各国的禽养殖业带来了巨大损失.自IBDV发现至今新的变异株不断出现,分子结构的改变导致病毒致病力的改变及宿主对疫苗应答的改变,使得传统的疫苗已不能控制其流行,因此各国学者对其基因组结构和功能进行了广泛深入的研究,并积极研制新型有效的疫苗以达到防治的目的.     

Development of a Novel Reverse Transcription Loop-Mediated Isothermal Amplification Method for Rapid Detection of SARS-CoV-2

In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.