Feasibility of enhanced phytoextraction of Zn contaminated soil with Zn mobilizing and plant growth promoting endophytic bacteria

Three bacterial endophytes of Sedum alfredii, VI8L2, II8L4 and VI8R2, were examined for promoting soil Zn bioavailability and Zn accumulation in S. alfredii. Results showed that three strains were re-introduced into S. alfredii rhizosphere soils under Zn stress and resulted in better plant growth, as roots biomass increased from 80% to 525% and shoot biomass from 11% to 47% compared with the uninoculated ones. Strains IVsLz, II8L4 and IVsR2 significantly increased shoot and root Zn concentrations in the ZnCO3 contaminated soil. Inoculation with strain IVsL2 resulted in 44% and 39% higher shoot and root Zn concentrations, while strain IV8R2 significantly decreased shoot Zn concentration in the Zn3（PO4）2 contaminated soils. In the aged contaminated soil, isolates IVsL2, IIsL4 and IVsR2 significantly increased root Zn concentration, but decreased shoot Zn concentration of Sedum alfredii. It suggested that endophytes might be used for enhancing phytoextraction efficiency.

Bioremediation of Soil Pollution in Orchard

[ Objective ] The aim was to study the bioremediation mechanism of soil pollution. [ Method ] The effects of applying biological organic fertilizers on the bioremediation of soil pollution in orchard were studid by experiment in orchard field and soil simulative experiment. [ Result] The biological organic fertilizers improved the activities of enzymes like polyphenol oxidase, urease, phosphatase, etc. in root-zone soil, promoted the passivation of heavy metals like Cd^2＋ , Pb^2＋ , Cr^3＋ , As^8＋ , etc. in root-zone soil, increased the quantities of useful active bacterium like beneficial fungi, actinomycetes, bacterium, etc. and decreased the quantities of harmful biology （like Fusarium oxysporum, Moniliophthora roreri, Ruselliniu necutrix/Helicobasidium mompa, nematode, etc. [ Conclusion] The study results provide some references for the popularization and application of biological organic fertilizers on fruit trees.

Finite element model updating and validating of Runyang Suspension Bridge based on SHMS

Based on the finite element （FE） program ANSYS, a three-dimensional model for the Runyang Suspension Bridge （RSB） is established. The structural natural frequency, vibration mode, stress and displacement response under various load cases are given. A new method of FE model updating is presented based on the physical meaning of sensitivity and the penalty function concept. In this method, the structural model is updated by modifying the parameters of design, and validated by structural natural vibration characteristics, stress response as well as displacement response. The design parameters used for updating are bounded according to measured static response and engineering judgment. The FE model of RSB is updated and validated by the measurements coming from the structural health monitoring system （SHMS）, and the FE baseline model reflecting the current state of RSB is achieved. Both the dynamic and static results show that the method is effective in updating the FE model of long span suspension bridges. The results obtained provide an important research basis for damage alarming and health monitoring of the RSB.

DELAY-TIME MODEL BASED ON IMPERFECT INSPECTION OF AIRCRAFT STRUCTURE WITHIN FINITE TIME SPAN

According to the failure characteristics of aircraft structure, a delay-time model is an effective method to optimize maintenance for aircraft structure. To imitate the practical situation as much as possible, imperfect inspections, thresholds and repeated intervals are concerned in delay-time models. Since the suggestion by the existing delay-time models that the inspections are implemented in an infinite time span lacks practical value, a de- lay-time model with imperfect inspection within a finite time span is proposed. In the model, the nonhomogenous Poisson process is adopted to obtain the renewal probabilities between two different successive inspections on de- fects or failures. An algorithm is applied based on the Nelder-Mead downhill simplex method to solve the model. Finally, a numerical example proves the validity and effectiveness of the model.

Weight-based shape modification of NURBS curves by constrained optimization

A new method for shape modification of non-uniform rational B-splines (NURBS) curves was presented, which was based on constrained optimization by means of altering the corresponding weights of their control points. Using this method, the original NURBS curve was modified to satisfy the specified geometric constraints, including single point and multi-point constraints. With the introduction of free parameters, the shapes of modified NURBS curves could be further controlled by users without destroying geometric constraints and seem more naturally. Since explicit formulae were derived to compute new weights of the modified curve, the method was simple and easy to program. Practical examples showed that the method was applicable for computer aided design (CAD) system.

Dynamic finite element model updating using meta-model and genetic algorithm

Current dynamic finite element model updating methods are not efficient or restricted to the problem of local optima. To circumvent these, a novel updating method which integrates the meta-model and the genetic algorithm is proposed. Experimental design technique is used to determine the best sampling points for the estimation of polynomial coefficients given the order and the number of independent variables. Finite element analyses are performed to generate the sampling data. Regression analysis is then used to estimate the response surface model to approximate the functional relationship between response features and design parameters on the entire design space. In the fitness evaluation of the genetic algorithm, the response surface model is used to substitute the finite element model to output features with given design parameters for the computation of fitness for the individual. Finally, the global optima that corresponds to the updated design parameter is acquired after several generations of evolution. In the application example, finite element analysis and modal testing are performed on a real chassis model. The finite element model is updated using the proposed method. After updating, root-mean-square error of modal frequencies is smaller than 2%. Furthermore, prediction ability of the updated model is validated using the testing results of the modified structure. The root-mean-square error of the prediction errors is smaller than 2%.

Amine-grafted on lanthanide metal-organic frameworks:Three solid base catalysts for Knoevenagel condensation reaction

A post-synthetic modification strategy has been used to prepare three solid base catalysts, including Er（btc）（ED）075（H2O）0.25 （2, btc = 1,3,5-benzenetricarboxylates, ED = 1,2-ethanediamine）, Er（btc）（PP）0.55（H20）0.45 （3, PP = piperazine）, and Er（btc）（DABCO）0.15（H2O）0.85 （4, DABCO = 1,4- diazabicyclo[2.2.2]octane）, by grafting three different diamines onto the coordinatively unsaturated Er（III） ions into the channels of the desolvated lanthanide metal-organic framework （Er（otc））. The resulting metal-organic frameworks were characterized by elemental analysis, thermogravimetric analysis, powder X-ray diffraction, and N2 adsorption. Based on its higher loading ratio of the diamine, as well as its greater stability and porosity, catalyst 2 exhibited higher catalytic activity and reusability than catalysts 3 and 4- for the Knoevenagel condensation reaction. The catalytic mechanism of 2 has also been investigated using size-selective catalysis tests.

OTFT with Bilayer Gate Insulator and Modificative Electrode

An organic thin-film transistor （OTFT） with an OTS/SiO2 bilayer gate insulator and a MoO3/AI electrode configuration between gate insulator and source/drain electrodes has been investigated. A thermally grown SiO2 layer is used as the OTFT gate dielectric and copper phthalocyanine（CuPc） is used as an active layer. This OTS/SiO2 bilayer gate insulator configuration increases the field-effect mobility, reduces the threshold voltage, and improves the on/off ratio simultaneously. The device with a MoO3/Al electrode has shown similar Ids compared to the device with an Au electrode at the same gate voltage. Our results indicate that using a double-layer of electrodes and a double-layer of insulators is an effective way to improve OTFT performance.

AN UPDATING METHOD FOR LOCAL MODEL ERRORS

The location of model errors in a stiffness matrix by using test data has been investigated by the others.The present paper deals with the problem of updating stiffness elements in the erroneous areas. Firstly,a model that bears relation to erroneous elements only is derived.This model is termed local errors model,which reduces orders and computational loads compared with global stiffness matrix. Secondly,an inverse eigenvalue method is used to update model errors. The results of a numerical experiment demonstrate that the method is quite effective.

Potentialities of Maize on the Removal of Organochlorine Pesticides from Contaminated Soils

In this paper, glasshouse experiments were conducted to determine the accumulation, distribution and transformation of DDTs and HCHs by maize under pot culture conditions. The culture soil was spiked with the organic pollutants and samples were collected in different durations. Analysis of the plants at harvest showed that the selected plant varied widely in their ability to remove and translo- cate DDTs and HCHs from the soil, the bioconcentration factor ranged from 0.004 to 0.027 for the shoot and from 0.036 to 0.097 for the roots, and the translocation factors were lower than 0.1 with variation between DDTs and HCHs, but no signifi- cant differences were observed. DDTs appeared to have accumulated by both pas- sive adsorption and active absorption, p,p＇-DDT and p,p＇-DDE were the major metabolite and the transformation was mediated by reductive dehalogenation, the affinity of the OCPs for lipids is one of the major factors affecting their uptake and translocation within the plants.

Surfactant-Enhanced Phytoremediation of Soils Contaminated with Hydrophobic Organic Contaminants:Potential and Assessment

Phytoremediation is becoming a cost-effective technology for the in-situ clean up of sites polluted with hydrophobic organic contaminants （HOCs）. The major factors limiting phytoremediation are the mass transfer, rate of plant uptake, and microbial biodegradation of HOCs. This article discusses the potential of surfactants to enhance desorption, plant uptake, and biodegradation of HOCs in the contaminated sites. Positive effects of surfactants on phytoremediation have been recently observed in greenhouse studies. The presence of some nonionic surfactants including polyoxyethylene sorbltan monooleate （Tween 80） and polyoxyethylene（23）dodecanol （Brij35） at relatively low concentrations resulted in significant positive effects on phytoremediation for pyrene-contaminated soil. However, the anionic surfactant （sodium dodecyl sulfate, SDS） and the cationic surfactant （cetyltrimethylammonium bromide, CTMAB） were not useful because of their phytotoxicity or low efficiency for surfactant-enhanced phytoremediation （SEPR）. The mechanisms of SEPR for HOC-contaminated sites were evaluated by considering experimental observations. In view of concerns about the cost effectiveness and toxicity of surfactants to plants, more research is needed to enhance the use of SEPR technology.

Construction of 2D Zn‐MOF/BiVO_(4)S‐scheme heterojunction for efficient photocatalytic CO_(2) conversion under visible light irradiation

The construction of S‐scheme heterojunction photocatalysts has been regarded as an effective avenue to facilitate the conversion of solar energy to fuel.However,there are still considerable challenges with regard to efficient charge transfer,the abundance of catalytic sites,and extended light absorption.Herein,an S‐scheme heterojunction of 2D/2D zinc porphyrin‐based metal‐organic frameworks/BiVO_(4)nanosheets(Zn‐MOF/BVON)was fabricated for efficient photocatalytic CO_(2)conversion.The optimal one shows a 22‐fold photoactivity enhancement when compared to the previously reported BiVO4 nanoflake(ca.15 nm),and even exhibits~2‐time improvement than the traditional g‐C3N4/BiVO4 heterojunction.The excellent photoactivities are ascribed to the strengthened S‐scheme charge transfer and separation,promoted CO_(2)activation by the well‐dispersed metal nodes Zn_(2)(COO)_(4)in the Zn‐MOF,and extended visible light response range based on the results of the electrochemical reduction,electron paramagnetic resonance,and in‐situ diffuse reflectance infrared Fourier transform spectroscopy.The dimension‐matched Zn‐MOF/BVON S‐scheme heterojunction endowed with highly efficient charge separation and abundant catalytic active sites contributed to the superior CO2 conversion.This study offers a facile strategy for constructing S‐scheme heterojunctions involving porphyrin‐based MOFs for solar fuel production.

Aliphatic amines modified CoO nanoparticles for catalytic oxidation of aromatic hydrocarbon with molecular oxygen

The surface modification of metal oxides using organic modifiers is a potential strategy for enhancing their catalytic performances.In this study,a hydrophobic surface amine-modified CoO catalyst with a water contact angle of 143°was fabricated.The catalyst was characterized by XRD,TGA,FT-IR,HR-TEM,and XPS.The results showed that the fabricated catalyst performed better than the hydrophilic commercial CoO nanoparticle in the process of aromatic hydrocarbon oxidation.After the amines modification,commercial CoO also became hydrophobic and improved conversion of ethylbenzene was achieved.The surface modification of CoO with amines induced the hydrophobicity property,which could serve as a reference for the design of other hydrophobic catalysts.

EXACT ANALYSIS OF OS MODIFIED VERSIONS WITH NONCOHERENT INTEGRATION

This paper deals with the exact detection analysis of the Ordered-Statistic(OS) processor along with OS Greatest Of(OSGO) and OS Smallest Of(OSSO) modified versions, for M postdetection integrated pulses when the operating environment is nonhomogeneous. Analytical results are presented in multiple-target case as well as in regions of clutter power transitions. The primary and the secondary interfering targets are assumed to be fluctuating in accordance with the SWII target fluctuation model. As the number of noncoherently integrated pulses increases,lower threshold values and consequently better detection performances are obtained in both homogeneous and multiple target background models. However, the false alarm rate performance of OSSO-CFAR(Constant False Alarm Rate) scheme at clutter edges is worsen with increasing the postdetection integrated pulses. As predicted, the OSGO-CFAR detector accommodates the presence of spurious targets in the reference window, given that their number is within its allowable range in each local window, and controls the rate of false alarm when the contents of the reference cells have clutter boundaries.

Two-stage optimization model for renewing warranty considering warranty deadline

Renewing warranty can provide customers with better service,and thus help manufacturers to gain market opportunities.In engineering practice,the cost for replacement is usually higher than the cost for maintenance,hence manufacturers often face huge challenge to reduce the warranty service cost.With consideration of the warranty deadline,we propose a two-stage optimization model for renewing warranty.In the first stage,a renewing warranty with deadline(RWD)policy is implemented,where the deadline represents the cumulative uptime threshold.When the cumulative uptime exceeds the deadline,the product will be minimally repaired and kept to the residual warranty period.When RWD is expired,the replacement warranty with limited repairs(RWLR)policy is applied.Under the free replacement and pro-rata warranty policy,the corresponding two-stage cost optimization model is established from the manufacturer’s perspective,the aim is to minimize the cost rate and obtain the optimal warranty period.A numerical example is provided to illustrate the validity of the proposed model,and the sensitivity analysis is also carried out.

A New Modification Michaelis-Arbuzov, Allen, Milobendzky-Shulgin, Michaelis-Becker and Raymond Reactions with Organic Compounds Arsenic, Antimony and Bismuth

In this work study, we investigated possibility of modifying the new Michaelis Allen, Milobendzky-Shulgin, Michaelis-Becker, Raymond reactions with organic compounds of arsenic, antimony and bismuth is discovered. A new mechanism for possible reactions has been proposed.

Light-driven activation of carbon-halogen bonds by readily available amines for photocatalytic hydrodehalogenation

A straightforward protocol using readily available aromatic amines,N,N,N',N'-tetramethyl-p-phenylenediamine or N,N,N',N'-tetramethylbenzidine,as photocatalysts was developed for theefficient hydrodehalogenation of organic halides,such as 4'-bromoacetophenone,polyfluoroarenes,cholorobenzene,and 2,2',4,4'-tetrabromodiphenyl ether(a resistant and persistent organic pollu-tant).The strongly reducing singlet excited states of the amines enabled diffusion-controlled disso-ciative electron transfer to effectively cleave carbon-halogen bonds,followed by radical hydrogena-tion.Diisopropylethylamine served as the terminal electron/proton donor and regenerated theamine sensitizers.

Obsolete Pesticides and Phytoremediation of Polluted Soil in Kazakhstan

In Kazakhstan, there are obsolete pesticides which should be buried in special dedicated and prepared burial sites or neutralized for minimization of dangerous genetic and ecological risks. The work in two years was identifying the obsolete pesticides in 91 the former warehouses of chemical plant protection products. In two regions （Almaty and Akmola regions） of Kazakhstan, the total amount of 388.6 tones of obsolete pesticides and unidentified stockpile material was observed, along with 513 pesticide containers. Results of the study have shown that soil around storehouses polluted by organochlorine pesticides residues in soil included metabolites of DDT （p, p＇-dichlorodiphenyltrichloroethane） and HCH （hexachlorocyclohexane）. The strategy was to identify pesticide-tolerant plant genotypes which can be used for phytoremediation of pesticide-contaminated soils in Almaty regions of Kazakhstan. The results have shown that selected wild species plants demonstrated ability to phytoaccumulation of organochlorine metabolites and reduce pesticide concentrations in soil （control without plant）. It was shown that accumulation of pesticides depended on the species of plants, plant biomass and pesticide concentrations in soil. The use of mineral fertilizers resulted in stimulation of growth and biomass accumulation followed by an increasing phytoextraction.

Finite element model updating for large span spatial steel structure considering uncertainties

In order to establish the baseline finite element model for structural health monitoring,a new method of model updating was proposed after analyzing the uncertainties of measured data and the error of finite element model.In the new method,the finite element model was replaced by the multi-output support vector regression machine(MSVR).The interval variables of the measured frequency were sampled by Latin hypercube sampling method.The samples of frequency were regarded as the inputs of the trained MSVR.The outputs of MSVR were the target values of design parameters.The steel structure of National Aquatic Center for Beijing Olympic Games was introduced as a case for finite element model updating.The results show that the proposed method can avoid solving the problem of complicated calculation.Both the estimated values and associated uncertainties of the structure parameters can be obtained by the method.The static and dynamic characteristics of the updated finite element model are in good agreement with the measured data.

Damage Assessment, Repair and Field Test of Steel Lattice Shell after Fire

A real case of a steel lattice shell suffering a fire was studied. Based on the theory of field modeling, fire dynamic simulator (FDS) was used to identify the temperature field. The damage mechanism of the structure was determined by FEM analysis. After damage assessment, the shell was repaired with the pipe-encasement method. Finally, field test was employed to check the capacity of the structure after repair. The numerical study results indicate that the damage assessment agrees well with field inspection, verifying the accuracy of fire numerical simulation and FEM analysis. The field test results prove that the pipe-encasement method is secure and reasonable, and the repaired shell is safe.