Changes in forest biomass carbon stock in the Pearl River Delta between 1989 and 2003

Forest ecosystems play a significant role in maintaining climate stability at the regional and global scales as an important carbon sink.Regional forest carbon storage and its dynamic changes in the Pearl River Delta have been estimated using the continuous biomass expansion factor(BEF)method based on field measurements of forests plots in different age classes and forest inventory data of three periods(1989–1993,1994–1998,1999–2003).The results show that regional carbon storage increased by 16.76%,from 48....     

水体的营养水平对苦草(Vallisneria atans)生长的影响

在室外控制条件下,以太湖梅梁湾水体现状营养水平(ρ(TN)为5 mg/L和ρ(TP)为0.2 mg/L)为依据,研究营养盐含量升高对苦草生长的影响.结果表明:①在满足光补偿点及无种间竞争等的条件下,苦草在营养水平为ρ(TN)＞10 mg/L和ρ(TP)＞0.4 mg/L的水中也能成活.②随着营养盐含量的升高,苦草生物量的增长率逐渐降低,当水中ρ(TN)达到10 mg/L和ρ(TP)达到0.4 mg/L时,苦草的生物量开始减少;营养盐含量升高对苦草叶片特征的影响不明显,而苦草根状茎的生物量却随着营养盐含量的升高而逐渐减少,当水体营养水平达到ρ(TN)为10 mg/L和ρ(TP)为0.4 mg/L时,除叶片长度外,苦草的其他形态指标值均显著下降.③在梅梁湾水体现状营养水平的基础上,当水中磷含量增加1倍时对苦草生长造成的抑制作用大于氮含量增加1倍时;当二者均增加时,对植物生长造成的抑制作用显著增加.     

Combination of biodiesel-ethanol-diesel fuel blend and SCR catalyst assembly to reduce emissions from a heavy-duty diesel engine

In this study, the efforts to reduce NOx and particulate matter （PM） emissions from a diesel engine using both ethanol-selective catalytic reduction （SCR） of NOx over an Ag/Al2O3 catalyst and a biodiesel-ethanol-diesel fuel blend （BE-diesel） on an engine bench test are discussed. Compared with diesel fuel, use of BE-diesel increased PM emissions by 14% due to the increase in the soluble organic fraction （SOF） of PM, but it greatly reduced the Bosch smoke number by 60%-80% according to the results from 13-mode test of European Stationary Cycle （ESC） test. The SCR catalyst was effective in NOx reduction by ethanol, and the NOx conversion was approximately 73%. Total hydrocarbons （THC） and CO emissions increased significantly during the SCR of NOx process. Two diesel oxidation catalyst （DOC） assemblies were used after Ag/Al2O3 converter to remove CO and HC. Different oxidation catalyst showed opposite effect on PM emission. The PM composition analysis revealed that the net effect of oxidation catalyst on total PM was an integrative effect on SOF reduction and sulfate formation of PM. The engine bench test results indicated that the combination of BE-diesel and a SCR catalyst assembly could provide benefits for NOx and PM emissions control even without using diesel particle filters （DPFs）.     

生物质慢速热解工艺的新探讨

慢速热解作为生物质气流床气化的前处理工艺在国内为首创。慢速热解方法不仅可以脱除生物质内的氧元素提高能量密度,而且可以改变生物质的物性有效解决生物质气流床气化过程的输送问题。文章分析了不同生物质种类热解后固体产物、液体产物和气体产物的特性,并且粗略衡算了热解过程的吸热量。结果表明:在热解温度<500℃时,液体产物和气体产物的热值随着热解温度的升高而增加;为得到高固体产率和能量产率的半焦作为气化原料,热解温度不宜>500℃;从能量衡算角度分析而得,热解过程的吸热量很少。     

生物质催化气化制氢技术研究

在人类面临严重的能源危机与环境污染的背景下,世界各国都在致力于对洁净能源氢的开发和研究,并取得了一定的研究成果。生物质气化制氢是一项富有前景的制氢技术,已引起了世界各国研究者的普遍关注。文章首先介绍了生物质气化制氢技术的国内外研究及应用现状,然后介绍了一种一体式生物质气化炉水蒸汽催化气化制氢的工艺流程,氢气体积的含量可达到50%以上。最后总结了这种工艺在各种制氢方法中,具有技术成熟、工艺简单,效率高等优点,有广阔的应用前景。     

Renewable energy potential in India and future agenda of research

ABSTRACT

Demand of electrical energy is exponentially increasing causing environmental problems due to extensive use of fossil fuels. Hence, research has been promoted in renewable energy technologies to mitigate environmental pollution. Indian subcontinent is rich in renewable energy sources (RES). This paper describes potential of RES and region-wise installed capacity in India. Estimated potential of RES is 57 GW which is targeted to be 175 GW by 2022. A logical framework for our future research work has been presented. This includes performance optimisation of solar pumping system and reliability assessments of the designed system using reliability indices.

Abbreviation: RES: Renewable energy resources; SHP: small hydro plants; GOI: Government of India; MNRE: Ministry of New and Renewable Energy; LHP: large hydropower; BCM: billion cubic metres; PEC: per-capita energy consumption; JNNSM: Jawaharlal Nehru National Solar Mission; DNI: direct normal irradiance; SPV: solar photovoltaic; UMPP: ultra mega green solar power project; GIS: geographic information systems; WMS: wind monitoring stations; MPWL: Madhya Pradesh windfarms Ltd.; MIB: mat river basin; SWAT: Soil and Water Assessment Tool; ROR: run of river; SMS: short message service; CDM: clean development mechanism; NIOT: national institute of ocean technology; LOLP: loss of load probability; CSO: Central Statistics Office; CEA: Central Electricity Authority; TERI: The Energy and Resources Institute; WPI: Wind Power India; IEA: International Energy Agency; EAI: Energy Alternatives India; BKP: Biomass Knowledge Portal; IRENA: International Renewable Energy Agency; GAIN: Global Agricultural Information Network; NITI: National Institution for Transforming India; NIWE: National Institute of Wind Energy; UP: Uttar Pradesh; J&K: Jammu and Kashmir; HP: Himachal Pradesh; NR: northern region; MP: Madhya Pradesh; WR: western region; TN: Tamil Nadu; AP: Andhra Pradesh; SR: southern region; ER: eastern region; NER: north eastern region; A&N: Andaman & Nicobar     

后石油时代沙生灌木直燃发电对环境的影响＊

文章通过对内蒙古中西部地区沙生灌木的成分分析,基于生命周期法(LCA),定量论证了沙生灌木直燃发电开发模式对环境的影响和推广的可行性,指出相比石油等传统能源,这种模式具有较大的潜在效益,对于我国发展绿色替代能源,促进西部地区生态环境和经济协调发展具有一定的战略意义。     

生物质燃烧的二噁英排放特性

通过室内模拟燃烧5种生物质,分别采集燃烧排放的烟气作为样品,然后分析生物质和燃烧产物的二噁英含量,得到玉米秸秆、稻草、松树、桉树、松针燃烧的二噁英排放因子分别为2.59、16.78、1.44、5.15、34.12 n.gkg-1,对应的I-TEQ浓度为0.26、1.04、0.10、0.31、1.49 n.gkg-1.O...     

人工湿地植物生物质资源能源化利用潜力评估

通过测定不同人工湿地植物的纤维素组分和热值,并采用NaOH–酶解工艺研究不同人工湿地植物水解液组分,对在人工湿地技术体系中起重要作用的湿地植物能源化利用潜力进行系统评估.结果显示,15种人工湿地植物的纤维素含量在19.78%～36.9%之间,半纤维素含量在4.51%～19.67%之间,木质素含量在10.79%～20.47%之间,具有与玉米秸秆相当的热值,其热值在14.002～17.839 MJ/kg之间.在NaOH–酶解工艺条件下,不同人工湿地植物水解液中存在5种糖类组分,主要为葡萄糖和木糖.研究表明,人工湿地植物是一种较好的生物质资源,可通过生物质固体成型燃料技术、沼气技术和燃料乙醇技术加以利用,进而建立人工湿地植物生物质资源能源化藕联利用模式.图2表2参22     

(N-[2-(2-氧-1-咪唑烷基)乙基]-N '-苯基脲(EDU)对环境臭氧胁迫下的水稻和小麦生长的影响

通过对作物定期喷施不同浓度(0、150、300和450 mg·L-1)的N-[2-(2-氧-1-咪唑烷基)乙基]-N'-苯基脲(ethy lenediurea,EDU)溶液,研究EDU对环境O3胁迫下水稻“粤晶丝苗2号”(Oryza sativa L.Yuejingsi 2)和小麦“北农9549”(Triticum a...