环境规制和农业科技进步的关系分析——基于波特假说的研究

波特假说主要从动态的角度论证了环境规制和农业科技进步之间的正向变亿关系.而在安徽省1990 -2008年的农业生产数据的基础上,选择合适的环境规制和农业科技进步的指标变量,运用Johansen协整分析方法验证了安徽省农业生产中的环境规制和农业科技进步的关系也符合这一假说,Granger因果关系检验说明了安徽省环境规制是农业科技进步产生的原因,脉冲响应分析和方差分析则更深入地从定量的角度分析了环境规制对农业科技进步影响滞后的趋势和影响程度.由实证分析可以看出,只是从静态角度来分析,环境规制是不利于农业的科技进步的;但从长期效益来看,环境规制有利于农业的科技进步.因此,在农业生态环境恶化的形势下,严格对农业废弃物的排放限制,制定较严格的农产品生产标准和产品质量标准,提高农民的环境意识和科技意识,通过强化环境规制来促使农业生产者提高农业生产技术,提高农产品品质和产品的市场竞争力就显得尤为重要.     

Toxicity of various anions associated with methoxyethyl methyl imidazolium-based ionic liquids on Clostridium sp

We investigated the effects on the growth of the anaerobic bacterium, Clostridium sp., of the ionic liquid, 1-methoxyethyl-3-methyl imidazolium [MOEMIM]⁺, derived from imidazolium cation and paired with one of a variety of counter-ions, viz., tetrafluoroborate [BF₄]^-, hexafluorophosphate [PF₆]^-_, trifluoroacetate [CF₃COO]^-, bis(trifluoromethane)sulfonamide [Tf₂N]^-, methane sulfonate [OMS], and 1-butyl-3-methyl imidazolium tetrafluoroborate [BMIM][BF₄]. These anions, in association with [MOEMIM]⁺ lowered the growth rate of the bacterium, showing the following trend: [Tf₂N]^- ≧ [PF₆]^- > [BF₄]^- > [CF₃COO]^- > [OMS]⁻. Anions incorporating fluorine were more toxic than those without it, and their toxicity rose with an increase in the number of fluorine atoms. Also, [MOEMIM]⁺[BF₄]^- was less toxic than [BMIM]⁺[BF₄]^-, probably due to the presence of a methoxyethyl functional group integrated in the cation side chain.     

Quantification of the inhibitory effect of methyl fluoride on methanogenesis in mesophilic anaerobic granular systems

The inhibitory effect of CH₃F on methanogenesis in mesophilic anaerobic granules was tested at different concentrations (0-10% v/v, in the gas phase) and verified by the stable carbon isotopic signatures of CH₄ and CO₂. The results showed that the inhibitory effect increased with the initial CH₃F concentration up to 5%. The CH₃F concentration causing 50% metabolic inhibition was 0.32%. Complete inhibition of acetoclastic methanogenesis with a 91% reduction in total methanogenic activity was achieved when 5% CH₃F was initially added to the headspace, which resulted in 870 μM dissolved CH₃F in the liquid. It was much higher than that applied in other natural anoxic non-granular systems, indicating that the layered granular structure influenced the inhibitory effect. The obvious increase in hydrogen content indicated that high concentrations of CH₃F (?5%) suppressed hydrogenotrophic methanogenesis as well. The stable inhibition lasted for at least 6 d as the CH₃F concentration decreased slowly with incubation time. These results suggested that CH₃F could be used for investigating methanogenic processes in anaerobic granular systems after the CH₃F concentration and incubation time for specific inhibition of acetoclastic methanogenesis were carefully determined. In the present system, CH₃F concentration of 5% was suggested to be optimal.     

乌江干流梯级电站生态调度现状分析

乌江是我国十三大水电基地之一,主要的开发任务为发电,其次为航运,兼顾防洪及其他。本研究在乌江干流上选取了4个具有代表性的断面,运用修正的Tennant法和综合法计算了维持乌江干流各代表性河段基本健康所需的生态需水量。研究表明,目前乌江干流梯级电站采取的调度措施能够满足各代表性河段所需的最小生态需水量。但目前的调度措施仍是建立在发电效益最大化基础上的,未能从干流生态环境系统的特殊要求进行调度,给干流生态环境造成了一定影响。本文最后提出了从多方面开展乌江干流梯级电站生态调度研究工作的建议。     

含钛炉渣制备光催化剂处理模拟甲基橙废水

以含钛炉渣为原料制得光催化剂PTC,PTC不仅对紫外光具有较大的吸收,且在可见光范围内也有明显的吸收。PTC是一种比表面积较大的多微孔材料。PTC对模拟甲基橙废水脱色的最佳工艺条件:PTC加入量为0.50g/L,废水pH为2。加入强氧化剂H2O2能提高模拟甲基橙废水的总脱色率,在初始质量浓度为50m g/L的模拟甲基橙废水中H2O2加入量为6m g/L时,废水总脱色率达80.96%,比不加H2O2时的废水总脱色率提高了31.36%。     

刚毛藻对Cu、Fe、Zn的耐受与污染控制研究

研究刚毛藻对Cu、Fe、Zn的耐受情况。实验设计了3种重金属的浓度,分别为00、.5 mg/L1、.0 mg/L、2.5 mg/L、5.0 mg/L、7.5mg/L1、0 mg/L的培养液,培养期间观察记录刚毛藻的长势,测定藻类生物量及叶绿素a的含量变化,研究藻体对模拟水中3种重金属的去除动态及实际去除效果。结果表明,3种重金属在低浓度(0.5—2.5 mg/L)时藻体长势较好;浓度达到5mg/L时开始出现毒害现象,表现为叶绿素a含量下降趋势;浓度达到7.5mg/L以上时藻体死亡。水体中有效Cu、Fe、Zn浓度较低时,藻体对3种重金属去除效果较好,较高浓度时由于毒害作用使其对3种重金属的去除能力下降。     

高校学生干部队伍团队精神培养初探

阐述了团队精神及其对于高校学生干部队伍的重要意义,结合所在高校学生干部队伍的现状进行了分析,发现目前高校学生干部队伍在团队精神培养工作方面存在部分学生干部自身素质欠缺、学生工作机制有待完善、培养方法与学生需求存在一定距离、学生干部间缺乏沟通等问题,并对其成因进行了剖析,尝试通过规范工作机制、创造交流机会、开展各种形式的团队实践活动等方法予以解决,以期为新时期高校学生干部队伍建设提供新思路。     

The profile of antibiotics resistance and integrons of extended-spectrum beta-lactamase producing thermotolerant coliforms isolated from the Yangtze River basin in Chongqing

The spreading of extended-spectrum β-lactamases (ESBL)-producing thermotolerant coliforms (TC) in the water environment is a threat to human health but little is known about ESBL-producing TCs in the Yangtze River. We received 319 ESBL-producing stains obtained from the Chongqing basin and we investigated antibiotic susceptibility, bla gene types and the presence of integrons and gene cassettes. 16.8% of TC isolates were ESBL-producing bacteria and bla_TEM+CTx-M was the predominant ESBL type. 65.2% of isolates contained class 1 integrons, but only 3 carried intI 2. Gene cassettes were amplified and sequenced. aadA, drfA, cmlA, sat1, aar3 and two ORF cassettes were found. In conclusion, Yangtze River is heavily polluted by ESBL-producing TC bacteria and the combined bla gene type could enhance antibiotic resistance. Class 1 integrons were widespread in ESBL-producing isolates and play an important role in multi-drug resistance. Characterization of gene cassettes could reveal the dissemination of antibiotic resistance genes.     

模拟可见光下掺杂TiO_2对甲醛溶液光催化降解

模拟自然条件下的可见光,以甲醛的光催化降解为探针反应,评价了通过溶胶-凝胶法分别制备的8种（银Ag、铜Cu、铁Fe、钨W、铈Ce、镧La、硫S、氯Cl）掺杂TiO2纳米晶体的光催化活性及对甲醛水溶液的去除效果。用X射线衍射、激光粒度分析和紫外-可见分光光谱表征了掺杂纳米TiO2的微晶尺寸、晶体结构与光学性能。结果表明：Ce离子尽管有较大的半径但是主要还是掺杂到晶格中,Ce掺杂可以促进TiO2由非正分锐钛矿相向锐钛矿相和金红石相的转变,抑制载流子复合,使TiO2的光吸收带边发生红移且有利于对可见光的吸收,从而使Ce掺杂TiO2在模拟可见光下光催化甲醛水溶液的能力得到明显提高。     

发达国家温室气体减排现状及对我国的启示

气候变化是当前全世界关注的焦点问题,大气中温室气体浓度的不断升高与人类活动存在密切的联系.温室气体的历史排放主要是由发达国家产生的,发达国家对气候变化负有主要的责任.目前发达国家温室气体减排履约的整体情况不容乐观,主要发达国家的排放量呈上升趋势,但一些发达国家的减排经验还是值得借鉴的.本文在总结发达国家温室气体减排政策和措施的基础上,结合我国实际情况,提出了我国温室气体减排的可能对策.