Study on Fly Ash Based Porous Ceramsite as Biological Filter Media

Using fly ash as a raw material,porous ceramic particles with an apparent density of 1.21 g/cm^(3),a visible porosity of 51.03%,and a specific surface area of 4.26 m^(2)/g were prepared and used as biofilter materials for wastewater treatment.Through SEM,XRD analysis,and heavy metal leaching analysis,it was found that porous ceramsite were porous materials with rough surfaces.After calcination,the newly formed mineral was silicate calcium feldspar.The heavy metal concentration in the leaching solution of porous ceramsite met the national surface water quality requirements.The treatment of domestic sewage showed that the volumetric loads of COD Cr,NH_(4)^(+)-N,and TN removed by the aerated biofilter were 5.23,0.98,and 0.35 kg/(m^(3)·d),respectively,with removal rates of 85.46%,96.13%,and 32.31%.

Study on Chromium Ion Adsorption from Wastewater by Sugarcane Residues

With the application of chromium increasing, wastewater shows an increase of chromium pollution. In particular, Cr(Ⅵ) has become a major concern because of its high toxicity. Cr(Ⅵ) is recognized to be much more toxic than Cr(Ⅲ). Sugarcane residue is a byproduct of the sugar industry, and it is an important renewable biomass resource. In this paper, sugarcane residues were used to remove chromium ions from wastewater in order to develop cheap and efficient heavy metal adsorption materials. The effects of pH, sugarcane residue dosage, sugarcane residue particle size and chromium ion initial concentration on chromium ion removal and the kinetics of chromium ion removal at normal temperature were investigated. The results showed that the removal rate of Cr(Ⅵ) and Cr(Ⅲ) increased with an increase of sugarcane residue concentration, and decreased with an increase of particle size and the initial concentration of chromium. The removal effect of Cr(Ⅲ) increased with increasing pH, and the removal effect of Cr(Ⅵ) decreased with increasing pH. The removal kinetics of chromium fitted well with a pseudo-second-order-model. Sugarcane residues had a higher adsorption capacity for Cr(Ⅲ) than for Cr(Ⅵ). This paper provides a basis for the treatment of chromium containing wastewater or other heavy metal wastewater in the future.

Studies on Removal of Ammonia Nitrogen From Wastewater Using Modified Corncob

Water pollution caused by ammonia nitrogen is of major concern in many parts of the world due to the danger it poses to the environment and human health.This study focuses on the development of an inexpensive and environmental adsorbent by means of modified corncob.The objective of this paper was to investigate the adsorption behavior of NH^+_4-N from wastewater by modified corncob.Corncob was modified with KMn O_4.The physico-chemical properties of modified corncob were characterized by fourier transform infrared spectroscopy(FTIR)and scanning electron microscopy(SEM).It was found that the adsorption capacity of corncob was improved significantly after modification with KMn O_4.The p H significantly affected the adsorption efficiency of modified corncob to NH^+_4-N.The best p H value of corncob adsorbing NH^+_4-N was 7.The coexistence of Na^+had a significant effect on the adsorption of NH^+_4-N.The adsorption process of modified corncob to NH^+_4-N followed the pseudo-first order kinetic model.Langmuir model could well simulate the adsorption behavior of NH^+_4-N on modified corncob.The maximum adsorption capacity of NH^+_4-N on modified corncob can reach 4.85 mg/g.The adsorption process of NH^+_4-N was monolayer adsorption.Moreover,modified corncob adsorbed NH^+_4-N was fertilizer conservation especially for nitrogen.The utilization of modified corncob with NH^+_4-N adsorption in the farmland could promote the gradual release of nutrients,thus providing nutrients for plant growth.It was proposed that if combined with biological method,the amount of removed NH^+_4-N from wastewater could be increased significantly.

Atomic Spin Polarization Controllability Analysis:A Novel Controllability Determination Method for Spin-Exchange Relaxation-Free Co-Magnetometers

This paper investigates the atomic spin polarization controllability of spin-exchange relaxation-free co-magnetometers(SERFCMs).This is the first work in the field of controllability analysis for the atomic spin ensembles systems,whose dynamic behaviors of spin polarization are described by the Bloch equations.Based on the Bloch equations,a state-space model of the atomic spin polarization for SERFCM is first established,which belongs to a particular class of nonlinear systems.For this class of nonlinear systems,a novel determination method for the global state controllability is proposed and proved.Then,this method is implemented in the process of controllability analysis on the atomic spin polarization of an actual SERFCM.Moreover,a theoretically feasible and reasonable solution of the control input is proposed under some physical constraints,with whose limitation of realistic conditions,the controller design can be accomplished more practically and more exactly.Finally,the simulation results demonstrate the feasibility and validation of the proposed controllability determination method.

Breeding and Cultivation Technique of Ditian 6

Ditian 6 is super sweet corn hybrid. Its parents are inbred line 201-2 and 769 respectively. It was certificated by Variety Certification Committee of Shanxi Province in 2013. Ditian 6 participated in regional trials of Shanxi Province in 2010 and 2011. The average fresh ear yield is 14257. 5 kg / ha. Its growth period is 81 d,belonging to the early variety. It has obvious advantages if it is early cultivated. The kernel is yellow,and the quality reaches a high level. In the early or late market,it has significant economic benefits. The variety has strong resistance to disease and adversity,with wide adaptability,high and stable yield. It can be planted in the areas where accumulated temperature is above 2300℃.

Effects of Quebracho Tannins on Growth Performance and Blood Routine of Simmental Fattening Cattle

[Objectives]The effects of condensed quebracho tannins on the production performance and blood routine indices of Simmental fattening cattle were investigated experimentally.[Methods]Twenty four Simmental fattening cattle were selected and randomly divided into two treatment groups according to their body weight,with 12 animals in each group.The diet of the control group consisted of beef cattle concentrate supplement+silage+hay,and the diet of the experimental group consisted of beef cattle concentrate supplement+silage+hay+tannins,and the experimental period was 30 d.[Results]Compared with the control group,the addition of tannins[30 g/(cattle·d)]to the diet of beef cattle increased the daily weight gain of Simmental beef cattle by 24.68%(P<0.01),while the feed conversion ratio decreased by 2.57%(P>0.05).The gross profit per cattle increased by 973.63 yuan,and the economic benefit increased by 114.78%.Platelets were higher in the experimental group than in the control group(P<0.01);hemoglobin was lower in the experimental group than in the control group(P<0.01);leukocytes,neutrophils,monocytes and lymphocytes were lower in the experimental group than in the control group(P<0.01);and erythrocytes were lower in the experimental group than in the control group(P<0.05).[Conclusions]This study provides a theoretical basis for the rational utilization of quebracho tannins.

Isolation and Characterization of Endophytic Fungi from Purslane and the Effects of Isolates on the Growth of the Host

Purslane, a common weed, has been used as food or folk medicine in many countries. The growth, medicinal components and nutrient contents of the plant are closely associated with endophytes, especially endophytic fungi. In this study, the endophytic fungi associated with purslane were isolated, and the effects of the isolates on the host were investigated to lay a foundation for further research and development of purslane resources. The results showed that a total of eight endophytic fungi were isolated from purslane (collected from Hohhot, Inner Mongolia, China), and they belonged to the genera Penicillium (isolates K, N, P, M and I), Chaetomium (isolate J), Fusarium (isolate H) and Petriella (isolate O). Moreover, the growth of purslane was significantly influenced by its endophytic fungi. Isolate M can significantly decrease the germination rate, while J can significantly increase the germination rate of purslane. In addition, H, J and M can significantly increase the bud length of purslane, and the fermentation broth of P has a negative influence on the bud length of purslane. M and I can significantly increase the height, fresh weight and chlorophyll content of purslane due, in part, to the lower pH of the fermentation broth of I and M.

Effects of Tourmaline on Dehydrogenase Activity of Activated Sludge

The black tourmaline produced in Lingshou of Hebei Province was characterized by X-ray diffraction and scanning electron microscope,and the effect of tourmaline on dehydrogenase activity of activated sludge was studied.The results showed that tourmaline increased the dehydrogenase activity of activated sludge and enhanced the stability of dehydrogenase to pH change.It made the pH value of activated sludge with different initial pH value tend to about 7.4,and improved the dehydrogenase activity of activated sludge.In addition to affecting water molecular groups,it was also related to maintaining the constant weak alkaline pH of the system.

微贮用植物乳杆菌固定化菌剂的制备

乳酸菌与纤维素降解菌因其可防止微贮饲料酸败、增加秸秆饲料的营养价值等优点,在秸秆微贮过程中起重要作用。但由于乳酸菌的繁殖会抑制纤维素降解菌的活性,如何实现微贮过程中两种微生物分时发挥功能是解决上述问题的关键。文中利用固定化技术将乳酸菌制备成含有玉米秸秆粉的固定化菌剂以达到缓释的目的。首先制作固定化空白小球得出复合固定化载体成球的最佳浓度,利用玉米芯吸附植物乳杆菌S1得到复合固定化载体,以对S1的包埋率、成球效果等为指标,通过对比两种固定化方法 (包埋法与包埋-交联法),得到固定化植物乳杆菌S1的最佳条件。研究表明,使用6%PVA+0.4%SA+0.3%CMC-Na进行包埋-交联时成球效果最好,使用1.2%SA+0.5%CMC-Na进行直接包埋时成球效果最好。通过对比5种固定化工艺,将1.2%SA+0.5%CMC-Na和吸附玉米粉组成的固定化载体混合物逐滴滴入4%氯化钙中直接包埋24 h得到的固定化小球其机械强度以及包埋率均优于其他工艺。因此,利用玉米芯吸附-海藻酸钠包埋的方法可以有效提高植物乳杆菌包埋效率,为使用固定化技术制备微贮饲料菌剂奠定基础。

基于PPy:PSS纳米纤维素复合材料的高性能柔性独立导电纳米纸用于超级电容器

本工作通过低成本、简单、快速的真空过滤方法首次成功制备了一种独立的、无粘合剂的柔性聚吡咯:聚磺苯乙烯/纤维素纳米纸电极(PPy:PSS/CNP).多层结构的纤维素纳米纸具有较高的表面积和良好的机械强度,不仅提供了高的电活性区域,缩短了电解质离子的扩散距离,而且还阻止了PPy在充电/放电过程中的体积膨胀/收缩.优化后的PPy:PSS/CNP在10 mV s-1时表现出3.8 F cm-2(对应于475 F cm-3和240 F g-1)的高比电容和良好的循环稳定性(在5000次循环后有80.9%的电容保持率).PPy:PSS/CNP在不同弯曲角度下的循环伏安曲线表明电极具有突出的柔韧性和电化学稳定性.此外,组装的对称超级电容器器件在功率密度为4.4 m W cm-2(550 m W c m-3)的情况下,提供了122μW h cm-2(15 W h cm-3)的高面积能量密度,这个值优于其他基于纤维素电极材料制备的器件.PPy:PSS/CNP电极结合了高电容性能、灵活性、易于制造和廉价多个优势,为开发下一代绿色、经济便携式和可穿戴电子产品提供了巨大潜力.

Facile microwave approach towards high performance MoS2/graphene nanocomposite for hydrogen evolution reaction

Low-cost, highly efficient catalysts for hydrogen evolution reaction(HER) are very important to advance energy economy based on clean hydrogen gas. Intensive studies on two-dimensional molybdenum disulfides(2 D Mo S2) have been conducted due to their remarkable catalytic properties.However, most of the reported syntheses are time consuming,complicated and less efficient. The present work demonstrates the production of Mo S2/graphene catalyst via an ultra-fast(60 s) microwave-initiated approach. High specific surface area and conductivity of graphene delivers a favorable conductive network for the growth of Mo S2 nanosheets, along with rapid charge transfer kinetics. As-produced Mo S2/graphene nanocomposites exhibit superior electrocatalytic activity for the HER in acidic medium, with a low onset potential of62 m V, high cathodic currents and a Tafel slope of43.3 m V/decade. Beyond excellent catalytic activity, Mo S2/graphene reveals long cycling stability with a very high cathodic current density of around 1000 m A cm^-2 at an overpotential of 250 m V. Moreover, the Mo S2/graphene-catalyst exhibits outstanding HER activities in a temperature range of 30 to 120°C with low activation energy of36.51 k J mol^-1, providing the opportunity of practical scalable processing.

MtROP8 is involved in root hair development and the establishment of symbiotic interaction between Medicago truncatula and Sinorhizobium meliloti

Emerging evidence has demonstrated that ROP GTPases play important roles in symbiosis,but the molecular mechanisms on their regulation in symbiosis are largely unknown.In this study,we showed that MtROP8 is involved in the symbiotic interaction between Medicago truncatula and Sinorhizobium meliloti.Expression analyses showed that MtROP8 was down-regulated in the early infected roots,but significantly up-regulated in nodules compared to the roots.Phenotypic analysis of RNA interference(RNAi)-mediated silencing of MtROP8 revealed that knock-down of MtROP8 expression resulted in various developmental defects of root hairs,including branched hairs,short bulbous root hairs,and even root hairs with apparent swollen bases,which were caused by the modification of the distribution and the levels of reactive oxygen species(ROS).Moreover,infection events were increased in transgenic roots harboring the MtROP8 RNAi construct in response to S.meliloti inoculation,concomitant with enhanced nodulation.These results indicate that MtROP8participates in root hair development and the establishmentof the symbiotic interaction by regulating ROS production and distribution.