Legume Green Manure and Intercropping for High Biomass Sorghum Production

Before the advent of cheap, synthetic fertilizers, legumes were commonly used as green manure crops for their ability to fix atmospheric nitrogen (N). A three-year study at Overton, TX examined legume integration into high-biomass sorghum (Sorghum bicolor L.) production systems on a Lilbert loamy fine sand recently cultivated after a fertilized bermudagrass [Cynodon dactylon (L.) Pers.] pasture. In this split-split plot design, ‘Dixie’ crimson clover (Trifolium incarnatum L.) and ‘Iron and Clay’ cowpea (Vigna unguiculata L.) were integrated into a high-biomass sorghum production system to evaluate impacts on N concentration, C concentration, and yield of high-biomass sorghum and their impacts on soil total N and soil organic carbon (SOC). Main plots were split into crimson clover green manure (CLGM) and winter fallow (FALL) followed by three sub-plots split into warm-season crop rotations: cowpea green manure (CPGM), cowpea-sorghum intercrop (CPSR), and sorghum monocrop (SORG). Three N fertilizer treatments (0, 45, 90 kg N∙ha−1) were randomized and applied as sub-sub plots. The CLGM increased (P sorghum biomass yield (16.5 t DM∙ha−1) 28% in year three but had no effect in the first two years. The CPSR treatment reduced sorghum yield up to 62% compared to SORG;whereas CPGM increased sorghum yield 56% and 18% the two years following cowpea incorporation. Rate of N fertilizer had no effect on sorghum biomass yield. Decrease in SOC and soil N over time indicated mineralization of organic N and may explain why no N fertilizer response was observed in sorghum biomass yield. Cowpea showed strong potential as a green manure crop but proved to be too competitive for successful intercropping in high-biomass sorghum production systems.

Evaluation and Selection of High Biomass Rice (<i>Oryza sativa L.</i>) for Drought Tolerance

Biomass production is important in increasing yield not only for food but also for bio-fuel production that depends on high dry matter. Due to climate change, occurrence of drought may be prevalent and this affects both grain and biomass yields in crops including rice. The objectives of this study were to determine the performance of selected high biomass breeding rice lines to different levels of drought and use several drought tolerance indices to identify best genotypes that could be grown in unfavorable water stressed areas. A rainfed and flooded trial was conducted to evaluate 20 selected breeding lines for biomass production and ten entries from the same set were grown in the greenhouse at three different field capacities (FC, 50%, 75%, 100%). Most of the genotypes performed well under non-stressed conditions (flooded and 100% FC) but some genotypes performed well in water stressed condition. The plants had lower plant height, tiller plant-1, and total biomass at maturity under rainfed conditions and their flowering was delayed compared to flooded conditions. In the greenhouse, water stress slowed the rate of increase in height, and produced lower shoot and root weight, percent dry matter (% DM) and total biomass. However, drought enhanced the rate of tiller production. Two genotypes were found to more tolerant to drought stress and could be used for cultivation under water stress condition to get optimum biomass yields. These genotypes can be identified using drought tolerance indices, particularly stress tolerance index (STI), geometric mean productivity (GMP), mean productivity (MP) and harmonic mean (HARM), as these have a similar ability to separate drought sensitive and tolerant genotypes. Genetic and molecular analyses, and detailed characterization of these genotypes will help understand their inheritance pattern and the number of genes controlling the traits and determine specific leaves and root traits important in developing high biomass rice.

A new horizontal in C1 chemistry: Highly selective conversion of syngas to light olefins by a novel OX-ZEO process

The most challenging goal of C1 chemistry is the control of C–C coupling to produce chemicals or fuels from C1 feedstocks,in particular syngas（H2/CO）,which can be derived from various carbon resources such as coal,natural gas or shale gas,and biomass.

Growth traits and nitrogen assimilation-associated physiological parameters of wheat(Triticum aestivum L.) under low and high N conditions

In this study, 14 wheat cultivars with contrasting yield and N use efficiency （NUE） were used to investigate the agronomic and NUE-related traits, and the N assimilation-associated enzyme activities under low and high N conditions. Under deficient-N, the cultivars with high N uptake efficiency （UpE） and high N utilization efficiency （UtE） exhibited higher plant biomass, yields, and N contents than those with medium and low NUEs. The high UpE cultivars accumulated more N than other NUE type cultivars. Under sufficient-N, the tested cultivars showed similar patterns in biomass, yield, and N content to those under deficient-N, but the varietal variations in above traits were smaller. In addition, the high UpE cultivars displayed much more of root biomass and larger of root length, surface area, and volume than other NUE type cultivars, indicating that the root morphological traits under N deprivation are closely associated with the plant biomass through its improvement of the N acquisition. The high UtE cultivars showed higher activities of nitrate reductase （NR）, nitrite reductase （NIR）, and gluta- mine synthetase （GS） at stages of seediling, heading and filling than other NUE type cultivars under both low and high N conditions. Moreover, the high UpE and UtE cultivars also displayed higher photosynthetic rate under deficient-N than the medium and low NUE cultivars. Together, our results indicated that the tested wheat cultivars possess dramatically genetic variations in biomass, yield, and NUE. The root morphological traits and the N assimilation enzymatic acitivities play critical roles in regulating N accumulation and internal N translocation under the N-starvation stress, respectively. They can be used as morphological and biochemical references for evaluation of UpE and UtE in wheat.

高海拔地区3种林分类型土壤酶活性与微生物生物量特征

为探究贵州省高海拔地区不同林分类型土壤酶活性和微生物生物量变化特征及其影响因素,以威宁县沙子坡林场云南松林、云南松-麻栎林和桤木-麻栎林两个土层(0~20、20~40 cm)为研究对象,测定3种林分类型土壤性质、微生物生物量含量及酶活性,采用方差、相关性及冗余分析方法研究不同林分类型的土壤性质、微生物生物量和酶活性的变化特征,揭示土壤酶活性、微生物生物量的影响因素。结果表明:3种林分类型土壤的脲酶(URE)、β-葡萄糖苷酶(βG)、蔗糖酶(SUC)活性无显著性差异,过氧化氢酶(CAT)、多酚氧化酶(PPO)活性均表现为桤木-麻栎林显著高于云南松-麻栎林和云南松林(P<0.05),酸性磷酸酶(ACP)活性在0~20 cm土层中云南松-麻栎林最低(P<0.05),20~40 cm土层中云南松林最低(P<0.05)。3种林分类型土壤的微生物生物量碳(MBC)和微生物生物量氮(MBN)含量均以云南松-麻栎林最高。冗余分析表明,土壤有机碳(SOC)、全磷(TP)含量是酶活性的影响因子,SOC含量、TP含量、无定形态氧化铝(Al_(o))含量、阳离子交换量(CEC)、无定形态氧化铁(Feo)含量和pH值是微生物生物量的影响因子,SOC含量是决定土壤酶活性和微生物生物量的关键因子。桤木-麻栎林和云南松-麻栎林土壤质量整体高于云南松林,在未来的森林经营中,该地区可以适当对云南松林进行树种结构的调整,以期进一步提升土壤质量。

Microorganisms in Small Patterned Ground Features and Adjacent Vegetated Soils along Topographic and Climatic Gradients in the High Arctic, Canada

In this study, we determine differences in total biomass of soil microorganisms and community structure (using the most probable number of bacteria (MPN) and the number of fungal genera) in patterned ground features (PGF) and adjacent vegetated soils (AVS) in mesic sites from three High Arctic islands in order to characterize microbial dynamics as affected by cryoturbation, and a broad bioclimatic gradient. We also characterize total biomass of soil microorganisms and the most probable number of bacteria along a topographic gradient within each bioclimatic subzone to evaluate whether differences in topography lead to differences in microbial dynamics at a smaller scale. We found total microbial biomass C, the most probable number of heterotrophic bacteria, and fungal genera vary along this bioclimatic gradient. Microbial biomass C decreased with increasing latitude. Overall, microbial biomass C, MPN and the number of fungal isolates were higher in AVS than in PGFs. The effects which topographic position had on microbial biomass C varied across the bioclimatic gradient as there was no effect of topographic position in Isachsen (subzone A) and Mould Bay (subzone B), when compared to Green Cabin (subzone C, warmer site).There was no effect of topographic position on MPN counts at Mould Bay and Green Cabin. However, in Isachsen, MPN counts were highest in the wet topographic position as compared to the mesic and dry. In conclusion, PGFs seem to decouple the effect climate that might have on the total biomass of soil microorganisms along the bioclimatic gradient;and influence gets ameliorated as latitude increases. Similarly, the effect of topography on the total microbial biomass is significant at the warmest bioclimatic zone of the gradient. Thus, climate and topographic effects on total microbial biomass increase with warmer climate.

Study of Alkali Metal Corrosion on Heating Surfaces and Bed Material Agglomerate in Biomass-fired Fluidized Bed Boiler

The bed material agglomeration and heating surface high-temperature Corrosion Problems of biomass-fired boiler in South China were studied in this work. The inner and outer surfaces of the corrosion sample were investigated by scanning electron microscope (SEM) with Bruker EDX and XRD. Results showed that the outer side of the corrosion sample was mainly composed of alkali chloride deposited ash, sulphide and a small amount of eutectoid;while the inner side of the corrosion sample was still mainly made up of the composition of SUS316, but added with alkali metal, oxygen, chlorine and sulphur elements, appearing as the corrosion products and eutectoid. It was thought that alkali chloride deposit and the reaction with pipe metal to generate low melting point eutectoid on the outer surfaces, or the corrosion reaction through the alkali metal sulphatization process was the main reasons leading to the damage of metal surface oxide film. Chlorine plays a role as haptoreaction in the corrosion process, and transports metal material as the form of chloride from the inner side to the outer side of the pipe surfaces by diffusion, accelerating the corrosion process. Meanwhile, the slag was studied by scanning electron microscope (SEM) with Bruker EDX, and the transformation process of slage was computationally analyzed by FACTSAGE. Results showed that the amount of alkali metal in the agglomerates was little, however, caused a great impact on severe agglomerates. The increase of temperature enhanced the conversion process of alkali metal to molten oxide, especially when the temperature was higher than760℃, the amount of molten product increased sharply. Thus, the temperature control of fluidized bed plays an important role in solving the problem of alkali metal agglomerates;it also reliefs the volatile of alkali metal into gas phase, benefiting the control of heating surface corrosion.

“双碳”背景下废弃生物质的高值化利用研究

以废弃棉花秸秆为原料,在500℃下热解制备了棉花秸秆活性炭(CSAC),并研究了对亚甲基蓝和酸性品红的吸附特性。同时,以CSAC为载体,采用水热法制备ZnO/CSAC,并初步探索其光催化特性。结果表明:室温下,投加量为6,25 g/L,吸附60,90 min时,CSAC对200 mg/L模拟亚甲基蓝和酸性品红废水的脱色率分别为99.66%和78.20%。对两种染料的吸附过程都更符合准二级动力学,受化学吸附控制,且为放热过程。可见光照射下,ZnO/CSAC的投加量为1 g/L,2 h时对200 mg/L亚甲基蓝的降解率可以达到91.20%。ZnO/CSAC中纳米ZnO呈二维片状组装成绒球状长在CSAC表面,活性反应点位增多,光催化性能良好。

施氮量对优质稻G优325氮肥利用率和产量的影响

【目的】探明优质杂交籼稻新品种G优325的适宜施氮量。【方法】设5个施氮量处理(0、60、120、180和240 kg/hm^(2),分别记为N0、N60、N120、N180和N240)进行田间试验,研究不同施氮量对G优325主要生育时期茎糵数、干物质积累与转运能力、氮肥吸收利用率和产量及其构成因素的影响。【结果】适当增加施氮量能显著提高G优325的产量,且在N180处理下产量最高。施氮量对产量构成因素、茎蘖数和干物质积累总量影响显著,随着施氮量增加,G优325成熟期的有效穗数、每穗总粒数和干物质积累总量均表现为先增加后降低的趋势,且有效穗数和干物质积累总量均在N180处理达到最高值,而每穗粒数在N120处理最多。随着施氮量增加,抽穗前后的干物质积累向籽粒的转运量均表现为处理N180>N240>N120>N60>N0;拔节期、抽穗期和成熟期的氮素积累总量均表现为先增加后降低的趋势,且均在N180处理下最高;氮素干物质生产效率、氮素稻谷生产效率、氮素收获指数、氮肥吸收利用率、氮肥农学利用率、氮肥偏生产力和氮素生理利用率均表现为处理N0>N60>N120>N180>N240。【结论】适宜提高施氮量(180 kg/hm^(2)),可协同实现优质杂交籼稻新品种G优325高产与较高氮肥利用效率。

铁精矿内配某生物质高温高压热解及其还原行为研究

以生物质为还原剂,在温度为1 040℃、压力为30 kPa下对铁精矿内配生物质热解气化及其还原行为进行研究。研究结果表明:初期热解产生了酚类等大分子碳氢氧化合物液相,并与铁精矿形成了焦油包裹体,显著迟滞了生物质挥发分的释放;外配水和铁精矿中的晶格氧促进了大分子碳氢氧化合物逐步氧化为酮类、酸类化合物,并最终转化为CO和H_(2)等还原性气体;铁精矿还原生成了铁晶须,部分形成了碳铁化合物,实现了铁氧化物的高效快速还原,入炉50 min时,金属化率达96.72%。

激光熔覆层在生物质电站环境下的高温腐蚀行为研究

与煤炭、天然气等燃料相比,生物质发热值低,含有更多种类且浓度更高的腐蚀性介质,燃烧后产生大量含氯、硫腐蚀气氛及其金属熔盐,导致生物质焚烧余热锅炉受热面高温腐蚀问题严重。现有在管材表面堆焊镍基耐腐蚀合金的技术尽管可显著提高管道服役寿命,但存在工作效率低、不适合现场施工、管道热变形等诸多问题。对此,采用常规激光熔覆、高速激光熔覆2种工艺在TP347H耐热钢表面制备了Inconel 625耐高温腐蚀涂层,对比研究了TP347H耐热钢熔覆Inconel 625合金涂层前后的长期高温腐蚀特性。采用扫描电镜(SEM)表征了制备态和500 h高温含氯腐蚀后的覆层显微组织;采用增重法定量评价了覆层前后TP347H耐热钢的耐腐蚀性能。结果表明:优化工艺参数条件下常规激光熔覆、高速激光熔覆制备覆层组织致密,2种覆层与基材结合强度分别为362.4 MPa和217.3 MPa,覆层稀释率分别为5.4%和0.9%。腐蚀增重结果表明,550℃模拟腐蚀条件下,激光熔覆、高速激光熔覆Inconel 625合金覆层的腐蚀速率分别约为TP347H耐热钢基材的17%和8%。650℃模拟腐蚀条件下,激光熔覆、高速激光熔覆Inconel 625合金覆层的腐蚀速率分别约为TP347H耐热钢基材的11%和7%。

温度对废弃生物质热解规律及产物分布的影响

为探究有机固体废弃物热解规律及产物分布,以不同原料(木屑、污泥、生活垃圾)为研究对象,利用一级固定床反应系统研究持续升温下不同生物质热解性能的变化规律。结果表明:高温有利于促进生物质热解、提高热解气产率、降低焦油产率,尤其木屑热解受温度变化作用显著;木屑、污泥、生活垃圾经高温热解后焦油所含有机物的分布差异明显,其中木屑热解油中未检测出酸类物质,酚类、醇类物质占比随温度变化明显增加,酮类化合物占比变化不大;进一步通过不同指标论证了生物质热解制备高值燃气的可行性,得出生物质高温热解气具有很好的协同作用和良好的应用前景,是生物质高值化利用的重要方向,也是绿氢产生的重要途径。

一株易转化、高生物量地衣芽孢杆菌的筛选与鉴定

【目的】地衣芽孢杆菌(Bacillus licheniformis)是发酵工业中表达异源蛋白的重要底盘细胞,筛选易转化和高生物量的B.licheniformis菌株,为有效提升宿主的改造效率和蛋白表达水平提供菌种资源。【方法】经过富集、gyrB扩增与16S rDNA序列分析从土壤中筛选与地衣芽孢杆菌同源性较高的菌株,将所筛菌株的电转效率和生物量与工业常用底盘细胞B.licheniformis 2709进行比较分析。对筛选出的易电转和高生物量菌株进行形态学与生理生化鉴定,并进行抗生素敏感性测定和高温碱性环境生长情况测定。【结果】筛选出10株与地衣芽孢杆菌同源性较高的菌株,其中菌株1-33电转化效率为6700 CFU/μg DNA,是B.licheniformis 2709的13.7倍。在豆粕玉米粉半固体培养基和SR液体培养基中培养,菌株1-33最大生物量达到5.2×10^(10) CFU/mL和6.8 g/L,分别为B.licheniformis 2709的1.71倍和1.3倍。进一步经过形态学、生理生化特性实验将菌株1-33最终鉴定为B.licheniformis,并表现出多种常用抗生素的敏感性和良好的耐碱与耐高温的能力。【结论】筛选出一株易电转和高生物量的B.licheniformis 1-33,为开发成高效表达外源蛋白的宿主菌奠定基础。

高值化等鞭金藻固碳研究进展

工业生产和人类活动释放的大量CO_(2)是造成全球性气候变暖的主要诱因。气候变暖往往伴随着极端恶劣天气的发生,对人类的生活、财产和基础设施构成严重威胁。为了减轻由此产生的负面影响和应对全球变暖,各国纷纷设定了碳达峰和碳减排目标,并致力于对CO_(2)进行固定和资源化利用。海洋等鞭金藻(Isochrysis galbana)具有生长速度快和固碳效率高的特点,集成废/污水处理和生物固碳,转化合成蛋白质、多不饱和脂肪酸等多种高值生物活性物质的等鞭金藻固碳技术,被认为是最有前途的碳捕获和资源高值化利用的技术之一。本文首先介绍和比较了常用的CO_(2)捕获技术的优缺点,强调基于等鞭金藻的碳捕获技术的适用范围和固碳效率的优势。其次阐明了海洋等鞭金藻光合固碳机制及其与卡尔文循环、三羧酸循环等代谢通路的联系;探讨光和CO_(2)对微藻固碳能力和胞内碳流分布的影响,探究培养条件、光生物反应器、基因工程/合成生物学技术改造藻株等影响等鞭金藻固碳效率的因素。最后,概述了等鞭金藻光合固碳与岩藻黄素、多不饱和脂肪酸、蛋白质等高值生物活性物质合成的关系,为精深加工、开发高值化等鞭金藻提供理论和实践依据,推动等鞭金藻固碳技术的发展和应用,协同推进节能减排,为助力实现“双碳”目标提供一条经济可行的新策略。

高温热解生物质焦含氧结构演变规律研究

为更高效清洁的利用生物质能,提高生物质热化学利用效率。使用13 NMR、FTIR与量子化学计算相结合的方法从微观尺度分析了高温稻壳焦和秸秆焦的结构演化规律。实验结果表明:高温下生物质焦含氧结构演变趋于同一性。芳香边界取代处的氧含量随温度升高而下降,羧基含量略有升高,其余结构形式的氧几乎不变。设计并计算了氧接芳香族结构与热解系统中游离基团的可能反应转化路径。与游离碳相结合形成新的羧基位于芳香边界是最可能发生的,反应释放能量68.11 kJ/mol。

烟草废弃物资源综合利用研究进展

在我国每年的烟叶种植与生产过程中可产生大量田间废弃物,如不加以处理不仅会严重威胁烟田生态环境,还会导致烟叶减产,因此,开展烟叶废弃物科学高效的资源化利用研究对烟草行业及其相关行业的可持续发展有着重要意义。综述了近些年高效利用烟草废弃物的主要途径及相关研究进展,包括茄尼醇、烟碱等高值化合物的提取和利用,有机堆肥的制备,生物质燃料制取,活性炭、纤维板和刨花板的制造等,旨在挖掘烟草剩余资源潜能并拓展其使用范围,以期实现烟草多用途高值利用的利益最大化,并推动烟草产业的健康发展。

生物质电厂灰作高性能混凝土掺合料的试验分析

生物质电厂灰获取便利且具有一定火山灰活性。为测试生物质电厂灰作高性能混凝土掺合料的可行性和性能影响,本文对生物质电厂灰进行了理化特性分析,对灰样进行了预处理,制备了10%,20%和30%掺量的高性能混凝土试块进行了抗压强度试验和抗氯离子渗透性能测试,结果表明以处理后的生物质电厂灰作高性能混凝土的掺合料,随掺量增加,高性能混凝土试块抗压能力减小,但总体满足强度要求;掺入生物质电厂灰可以提高高性能混凝土抗氯离子侵蚀能力。

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生物质是地球上最丰富的可再生碳资源之一,在实现“双碳”战略目标方面扮演着重要作用。生物质热解是一项极具前景的生物质利用技术,其中热解形成的生物油有望取代传统化石能源,用于生产高值燃料或化学品。然而,生物质热解是一个十分复杂的过程,该过程及热解产物分布受诸多因素影响。因此,发展生物质热解动力学模型对指导热解工艺生产十分重要。动力学模型的研究不仅可以揭示热解过程中所涉及的物理化学变化,还可以预测热解反应速率及主要产物分布。早期构建的全局动力学模型为热解机理的理解与更详细模型的发展奠定了基础。随着生物质热解的主要研究目标由最大化生物油产量转变为最大化高附加值化学品产量,包含更多热解机理信息和可预测更多单个产物产率的半详细和详细动力学模型开始出现。主要介绍了生物质热解动力学模型的研究现状,将动力学模型分为全局模型、半详细模型和详细模型,并对未来生物质热解动力学研究及详细模型的发展进行了展望。

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综述了近年来用于木质素解聚的光催化剂种类,分析了木质素光催化解聚机理及策略,还对光催化与多种技术耦合的解聚方法进行了介绍,并展望了木质素光催化解聚研究领域所面临的挑战及发展方向。

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化石能源的大规模使用使得大气中CO_(2)的含量不断增加。发展生物质能源等可再生能源,结合CO_(2)的转化利用对降低化石能源的依赖和减少碳排放具有重要的意义。利用可再生电能驱动CO_(2)的电化学还原生成燃料和化学品是CO_(2)转化利用的一个有效途径。本文对CO_(2)电化学转化以及耦合生物质氧化转化新路线的主要研究进展进行了综述。重点介绍了CO_(2)电化学还原的催化剂、反应系统、反应机制等方面的最新进展,以及阳极耦合生物质及其衍生醇类、醛类等氧化转化的新技术。可再生电能驱动的生物质氧化转化与CO_(2)电还原相耦合不仅可以获得高值化学品,而且可以显著减少CO_(2)的净排放。因此,本文可为生物质和CO_(2)转化提供新的思路。