大变形巷道弹性锚喷混凝土耦合支护技术研究及应用

为提高层理地质条件下大变形巷道的稳定性,延长巷道使用寿命,采用具有较大变形承载能力的喷钢纤维混凝土与弹性锚杆耦合支护技术加固围岩。首先研究层理状地质条件下高应力软岩巷道的破坏特点及规律,确立支护结构和时效耦合的关系,并通过钢纤维混凝土试样的动静荷载试验,研究混凝土强度与钢纤维掺量的关系,得到喷钢纤维混凝土合理的钢纤维掺量。此外,针对大变形巷道开挖初期变形量大、破坏速度快的特点,设计具有让压吸能作用的新型弹性锚杆,并将此弹性锚杆结合喷钢纤维混凝土技术进行工业试验,试验的位移监测结果表明:该方案位移量比原方案减小约50%,且支护10个月后未出现裂缝。     

复合式膜生物反应器中EPS的分布特征及其与膜污染的关系

采用复合淹没式膜生物反应器(Hybrid Membrane Bioreactor,HMBR)处理城市污水,对反应器污水处理效果、胞外多聚物(Extracellular Polymeric Substances,EPS)在反应器中的分布及其与膜污染的关系等问题进行了系统研究.结果表明,反应器出水中SS、COD、BOD5、氨氮的去除率都在93％以上,出水水质稳定.反应器混合液中松散态EPS( Loosely Bond EPS,LB-EPS)和固着态EPS(Tightly Bond EPS,TB-EPS)都随着运行时间而增加,并且与跨膜压差(Trans-Membrane Pressure,TMP)的变化存在较强的线性相关关系(R2=0.89);填料生物膜上EPS的质量比随着运行时间的增加也有上升趋势,但与膜污染没有明显的相关关系( R2=0.55);泥饼层中TB-EPS的质量比远高于LB-EPS,EPS与表征膜污染程度的TMP明显相关(R2 =0.91),EPS在泥饼层中的积累是造成膜污染的重要因素之一.     

大辽河表层水中邻苯二甲酸酯分布特征及环境健康风险评价

利用气相色谱-质谱(GC-MS)检测了大辽河表层水中邻苯二甲酸酯类(PAEs)有机污染物的浓度水平,分析其分布特征,并对PAEs类有机污染物的环境健康风险进行了评价。结果表明,大辽河表层水中共检出4种PAEs,其质量浓度范围为n.d.#0.754μg·L~(-1)。4种PAEs类中质量浓度平均值最高的为邻苯二甲酸二异辛酯(DIOP)(0.36μg·L~(-1)),最低的为邻苯二甲酸二甲酯(DMP)(0.01μg·L~(-1))。4种PAEs浓度贡献大小依次为:邻苯二甲酸二异辛酯(DIOP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二甲酯(DMP)。DBP浓度基本符合国家地表水环境质量标准(GB3838—2002)。与国内其他水域相比,大辽河表层水中PAEs的污染程度处于较低水平。DMP和DEP的最高值均出现在营口市区最主要的工业和生活污水排污口之一——纱厂潮沟采样点,DBP和DIOP的最高值则分别出现在牛庄大桥和港监潮沟采样点。总PAEs类有机污染物分布趋势为:在工业分布较多的区域及主城区附近水域PAEs浓度较高,大辽河上游区域PAEs浓度相对较低。利用US EPA健康风险评估模型粗略估算,大辽河表层水中PAEs类污染物的非致癌风险指数值低于1。     

无机离子对左旋葡聚糖光降解的影响

左旋葡聚糖(LG)被广泛作为生物质燃烧的示踪剂.然而,近年来研究表明左旋葡聚糖在大气中不稳定而会发生光降解.此外,对于大气中含量较高的SO₄^2-、NO₃-、NO₂-无机离子对LG光解的影响罕有报到.为此,本文模拟了液相中SO₄^2-、NO₃-、NO₂-对LG光氧化行为的影响.结果表明,Na2SO₄、NaNO₃、NaNO₂条件下LG光解速率常数分别为0.208、0.182、0.165 min^-1,均低于对照组(0.266 min-1),这表明无机离子的存在会减缓LG光降解速率.此外,这3种无机离子对LG光解产物中的低分子脂肪酸分布,甲酸/乙酸(C1/C2)比率均有重要的影响.其中,SO₄^2-存在下产物中戊二酸较多、NO₃-存在下产物中甲酸较多、NO₂-存在下产物中乙酸较多;NO₂-存在下产物中的C1/C2比率小于1与一般二次源中的C1/C2比率不一致,这表明由单一反应引起的C1/C2并不总是大于1.这些结果对于我们深刻理解大气液相中的有机物转化具有重要的参考价值.     

Assesment of disinfection by‐products removal by ozonation coupled with adsorption

This research work was performed to evaluate ozonation and granular activated carbon adsorption processes from the view‐point of controlling the formation of disinfection by products (DBPs). Both the humic acid and raw water were first preozonated and then adsorbed on the activated carbon to assess the potency for removal of total organic carbon (TOC) and DBPs. The disinfection by‐product including THMs and HAAs, in principle, can be successfully removed through a use of the ozonation and granular activated carbon (GAC) adsorption processes. However, in practice dealing with the raw water, it is necessary to introduce the pilot‐plant to obtain the design and operation guidelines for the water treatment plant through the ICA (Instrumentation Control and Automation) program in our future research work.     

Scaling up of biomass simulation for Eucalyptus plantations based on landsenses ecology

ABSTRACT

Sustainable forest management on a regional scale requires accurate biomass estimation. At present, technologically comprehensive forecasting estimates are generated using process-based ecological models. However, isolation of the ecological factors that cause uncertainty in model behavior is difficult. To solve this problem, this study aimed to construct a meliorization model evaluation framework to explain uncertainty in model behavior with respect to both the mechanisms and algorithms involved in ecological forecasting based on the principle of landsenses ecology. We introduce a complicated ecological driving mechanism to the process-based ecological model using analytical software and algorithms. Subsequently, as a case study, we apply the meliorization model evaluation framework to detect Eucalyptus biomass forest patches at a regional scale (196,158 ha) using the 3PG2 (Physiological Principles in Predicting Growth) model. Our results show that this technique improves the accuracy of ecological simulation for ecological forecasting and prevents new uncertainties from being produced by adding a new driving mechanism to the original model structure. This result was supported by our Eucalyptus biomass simulation using the 3PG2 model, in which ecological factors caused 21.83% and 9.05% uncertainty in model behavior temporal and spatial forecasting, respectively. In conclusion, the systematic meliorization model evaluation framework reported here provides a new method that could be applied to research requiring comprehensive ecological forecasting. Sustainable forest management on regional scales contributes to accurate forest biomass simulation through the principle of landsenses ecology, in which mix-marching data and a meliorization model are combined.     

Kinetics of acetyl CoA: Arylamine N‐acetyltransferase from rapid and slow acetylator fish tissues

N‐acetyltransferase (NAT) activity was determined in 100 fish (Oreochromis mossambicus) livers using 2‐aminofluorene and p‐aminobenzoic acid as substrates. Overall, the liver NAT activity of the 50 females was higher than the liver NAT activity of the 50 males. The activities (mean ± SD) of NAT from kidney, blood, intestine, and liver of males was 0.42 ± 0.11, 0.12 ± 0.03, 0.12 ± 0.08, and 1.56 ± 0.54 nmol/min/mg protein for the acetylation of 2‐aminofluorene and 0.36 ± 0.09, 0.09 ± 0.01, 0.11 ± 0.04, and 0.46 ± 0.15 nmol/min/mg protein for the acetylation of p‐aminobenzoic acid. In kidney, blood, intestine, and liver from female fish, the activities obtained were 1.60 ± 0.12, 0.35 ± 0.07, 0.15 ± 0.09, and 1.89 ± 0.50 nmol/min/mg protein for 2‐aminofluorene and 0.95 ± 0.11, 0.27 ± 0.03, 0.13 ± 0.09, and 0.57 ± 0.12nmol/min/mg protein for p‐aminobenzoic acid. Kinetic constants for arylamine N‐acetyltransferase activity in kidney, blood, intestine, and liver from fish with rapid, intermediate, and slow acetylator activity were determined. Apparent K _m and V _max values for 2‐aminofluorene were 5.5 and 7‐fold higher for liver than for the other tissues. Apparent K _m and V _max values for p‐aminobenzoic acid were 3.5 and 4.7‐fold higher for liver than for the other tissues. Based on the 2‐aminofluorene NAT activity of liver, there appears to be a polymorphism in NAT activity with 16 rapid, 28 intermediate, and 56 slow acetylators among the 100 fish assayed. This is the first demonstration of acetyl CoA: arylamine N‐acetyltransferase activity in fresh water fish and could lead to the development of a fish model for monitoring the effect of pollution of water environments on native species.     

Light‐induced changes in rabbit pineal gland n‐acetyltransferase activity

N‐acetyltransferase (NAT) activity was determined in different ages of New Zealand White rabbit pineal gland using 2‐aminofluorene and p‐aminobenzoic acid as substrates and it was assayed by high pressure liquid chromatography. Rabbits of different ages were either sacrificed during the light phase, exposed to darkness or light for 1 min during the dark phase of the lighting cycle, returned to their cages in darkness for 30 min and then sacrificed. Pineal gland NAT activity in animal nocturnally exposed to 1 min of light was inhibited in animals 1 ‐day‐old of age. Nocturnal light exposure did not inhibit enzyme activity in 1‐day‐old rabbit, even though these animal displayed clear light : dark differences in pineal gland NAT activity. Nocturnal light exposure also did not inhibit night time levels of NAT activity in 1‐day‐old animals who had been bilaterally enucleated. The result suggested that this effect is retinally mediated. Pre‐treatment of 1‐day‐old and 60‐day‐old animals with the isoproterenol (beta‐noradrenoreceptor agonist drug), prevented the nocturnal light‐induced inhibition of NAT activity. The different sensitivity of 60‐day‐old and 1‐day‐old animals to different illuminances or durations of nocturnal light exposure, was that the duration or intensity of light exposure was enable to inhibit nocturnal NAT activity. The NAT activity was at least 3.2‐ to 4.6‐fold greater in 1‐day‐old rabbits compared to 60‐day‐old rabbits. Kinetic constants for arylamine NAT activity in pineal gland from rabbits were determined. K_m and F_max values for 2‐aminofluorene were 2.6‐fold higher for light exposure than for no light exposure rabbits. This is the first demonstration of the retina‐pineal gland pathway appears light‐induced changes in pineal glands of animals in 1‐day‐old of ages or older; but this pathway does not function in 60‐day‐old rabbits like manner in 1‐day‐old rabbits.     

Paeonol promotes arylamine N‐acetyltransferase activity in human bladder tumor cells

Paeonol was used to determine effects of arylamine N‐acetyltransferase (NAT) activity in human bladder tumor cells. The NAT activity was measured by high performance liquid chromatography assaying for the amounts of N‐acetyl‐2‐aminofluorene (2‐AAF) and N‐acetyl‐p‐amino‐benzoic acid (N‐Ac‐PABA) and remaining 2‐aminofluorene (2‐AF) and p‐aminobenzoic acid (PABA). The NAT activity in human bladder tumor cells was promoted by paeonol in a dose‐dependent manner, i.e. the higher the concentration of paeonol, the higher the promotion of NAT activity. The data also indicated that paeonol increases the apparent values of K_m and K_max from human bladder tumor cells in cytosols and intact cells. This report is the first demonstration to show paeonol did promote human bladder tumor cell NAT activity.     

Longevity of organic layers of vertical flow ponds for sulfate reduction in treating mine drainages in South Korea

This study was carried out to evaluate longevity of available organic materials used for sulfate-reducing bacteria (SRB) activity in vertical flow ponds (VFPs) to treat mine drainage in South Korea. Spent mushroom compost samples (SMC) were tested as substrates in VFPs and analyzed for total organic carbon in VFPs, and were collected to analyze total organic carbon (TOC), T-N, T-P, K, metals and residual cellulose to check the longevity assessment. Chemical analysis revealed that the average contents of Fe, Al and Mn in SMC of VFPs were 19,907, 32,137 and 434 mg/kg, respectively. The contents of Fe and Al in SMC of VFPs were much higher than those of the unused SMC (control), but to the contrary, those of Mn showed a reversed tendency. Average TOC content of the controls was 64.19% but in one of the VFP substrates was as low as 15.92%. This might be resulted from SRB consumed the available organic carbon in SMC as VFPs system aged. Contents of T-N in VFPs tended to decrease as VFPs aged. The residual cellulose ranged from 3.88 to 6.72% (g/g). There existed a negative relationship between residual cellulose contents and ages of VFPs. Assuming that SMC in all VFPs had similar compositions when the VFPs were initially established, trend analysis predicted that the amount of carbon source for SRB might be available for 12–15 years further, depending on VFPs.