Application of liquid cattle manure and inorganic fertilizers affect dry matter,nitrogen accumulation,and partitioning in maize

Efficient use of N applied in the form of organic and inorganic fertilizers is important in maize (Zea mays L.) production to maximize producer’s economic returns and maintain soil and water quality. A field study was conducted for three consecutive years (2003–2005) in Thessaloniki, Greece to investigate whether liquid cattle manure can be used to replace inorganic fertilizers and also whether inorganic fertilizer can be applied preplant or as a combination of preplant and sidedress and can affect maize growth, development and N use efficiency. The treatments were control (unfertilized), liquid dairy cattle manure (Manure), application of 260 kg N ha⁻¹ year⁻¹ as basal dressing (N-single), application of 130 kg ha⁻¹ year⁻¹ N as basal dressing before sowing and 130 kg N ha⁻¹ when plants were at the eight-leaf stage (V8) (N-split). In 2 out of the 3 years of the study there was a significant positive effect of fertilizer application on maize growth, development, N uptake, and partitioning compared with the control. Dry matter production was increased by an average of 39% during the 2 years in plots fertilized either with manure or inorganic fertilizers than the control plots. Also from the yield components kernel weight per ear and number of kernels per ear were increased by an average of 35% and 32%, respectively in the fertilized plots compared with the control plots. Chlorophyll level was affected as it was increased by an average of 18%, 14%, and 18% at the ten-leaf stage (V10), silking and milk stage, respectively in the fertilization treatments compared with the control. Similar trend was observed in the other parameters that were studied. No differences were found between the manure and the different times of N application which indicates that manure can be used to replace inorganic fertilizer. Applying N either preplant in a single application or in split application (half of N preplant and half as sidedress) did not have any effect on any characteristics that were studied indicating that preplant application can be used as it is more cost effective. The present study indicates that liquid cattle manure can be used to replace inorganic fertilizers and also that there was no difference between preplant and sidedress application of N.     

Improvements to and limitations of Latin hypercube sampling

Two techniques are proposed to improve the performance of Latin hypercube sampling. To improve the statistics for each variable, it is proposed that realizations for each variable be acquired by finding the probabilistic means of equiprobable disjunct intervals in the variable's domain, instead of using the cumulative distribution function directly, as is currently done. To reduce error in correlations between variables (correlated or uncorrelated), it is proposed to perform a single-switchoptimized method on the realizations for one variable at a time, instead of using matrix manipulation, as is the current custom. Limitations in hypercube sampling will be discussed, and numerical results involving a simple Poisson process will be offered.     

Self-monitoring query execution for adaptive query processing

Adaptive query processing generally involves a feedback loop comprising monitoring, assessment and response. So far, individual proposals have tended to group together an approach to monitoring, a means of assessment, and a form of response. However, there are many benefits in decoupling these three phases, and in constructing generic frameworks for each of them. To this end, this paper discusses monitoring of query plan execution as a topic in its own right, and advocates an approach based on self-monitoring algebraic operators. This approach is shown to be generic and independent of any specific adaptation mechanism, easily implementable and portable, sufficiently comprehensive, appropriate for heterogeneous distributed environments, and more importantly, capable of driving on-the-fly adaptations of query plan execution. An experimental evaluation of the overheads and of the quality of the results obtained by monitoring is also presented.     

LabVIEW-based sequential-injection analysis system for the determination of trace metals by square-wave anodic and adsorptive stripping voltammetry on mercury-film electrodes

The development of a dedicated automated sequential-injection analysis apparatus for anodic stripping voltammetry (ASV) and adsorptive stripping voltammetry (AdSV) is reported. The instrument comprised a peristaltic pump, a multiposition selector valve and a home-made potentiostat and used a mercury-film electrode as the working electrodes in a thin-layer electrochemical detector. Programming of the experimental sequence was performed in LabVIEW 5.1. The sequence of operations included formation of the mercury film, electrolytic or adsorptive accumulation of the analyte on the electrode surface, recording of the voltammetric current-potential response, and cleaning of the electrode. The stripping step was carried out by applying a square-wave (SW) potential-time excitation signal to the working electrode. The instrument allowed unattended operation since multiple-step sequences could be readily implemented through the purpose-built software. The utility of the analyser was tested for the determination of copper(II), cadmium(II), lead(II) and zinc(II) by SWASV and of nickel(II), cobalt(II) and uranium(VI) by SWAdSV.     

Physically based modeling of shear modulus‐temperature relationship for thermosets

A new physically based model for the simulation of the imaginary part of the shear modulus‐temperature (G″‐T) curve of thermosets is introduced in this paper. The model is based on the modification of the G″‐T equation used for thermoplastic polymers via the introduction of two new formulations regarding the calculation of the configuration probability and the velocity matrix of the examined thermosets. The formulations for the calculation of the probability of configuration and the velocity matrix of the polymer chain were modified according to the cross‐linking structure of thermosets. In addition, an arctangent function is proposed to consider the effect of temperature on the mean square separation of the ends of the sub‐molecules. All the parameters necessary to calibrate the model can be either estimated or experimentally derived using low‐frequency dynamic mechanical analysis. The newly introduced model is based on a sound physical background, and can be used for the investigation of the effect of the molecular structure of thermosets on their loss modulus and their glass transition temperature. POLYM. ENG. SCI., 55:2893–2898, 2015. © 2015 Society of Plastics Engineers     

A novel approach to resource scheduling for parallel query processing on computational grids

Advances in network technologies and the emergence of Grid computing have both increased the need and provided the infrastructure for computation and data intensive applications to run over collections of heterogeneous and autonomous nodes. In the context of database query processing, existing parallelisation techniques cannot operate well in Grid environments because the way they select machines and allocate tasks compromises partitioned parallelism. The main contribution of this paper is the proposal of a low-complexity, practical resource selection and scheduling algorithm that enables queries to employ partitioned parallelism, in order to achieve better performance in a Grid setting. The evaluation results show that the scheduler proposed outperforms current techniques without sacrificing the efficiency of resource utilisation. Recommended by: Ioannis Vlahavas     

Effect of storage temperature and size of stalks on quality of minimally processed leeks

Minimally processed leek stalks were produced by trimming of freshly harvested leeks (Allium porrum L.) to sizes of 0–22, 0–11 and 11–22 cm. Trimmed stalks were then stored at 0, 10 and 20 °C in air for 8 days to determine the effects of temperature and stalk size on quality during storage, including inner leaf growth, fresh weight loss and discoloration. Both inner leaf growth and fresh weight loss were increased linearly with storage duration. Growth of cut leek inner leaves was significantly reduced to 4 mm at the end of 0 °C storage in all three types of cut stalks. Inner leaf growth was maximized during storage at 10 and 20 °C in 0–11 cm stalks, medium in 0–22 cm stalks and minimal in 11–22 cm stalks. Fresh weight loss of 0–11 cm size was significantly higher than that of 0–22 cm size at both 0 and 10 °C, whereas there was no difference between 0–11 and 11–22 cm sizes. At 10 and 20 °C the 0–11 cm size lost more weight than the 11–22 and 0–22 cm ones. Differences in color attributes were observed in most cases between stalk sizes, due to different coloration of intact leeks. Discoloration was observed particularly at the stalk base at 20 °C. Low temperatures effectively control discoloration, and reduce considerably inner leaf growth of minimally processed leeks, but do not control it. Copyright © 2005 Society of Chemical Industry     

Radio Frequency Vacuum Drying of Wood. III. Two-Dimensional Model, Optimization, and Validation

A simple two-dimensional model is presented for the radio frequency vacuum drying of thick timbers. The developed code is linked to powerful optimization methods to account for the variability of the permeability and the internal pressure deviation from the saturated vapor pressure above the fiber saturation point. The model is compared with recently obtained experimental results where the radio frequency heating source is an amplifier. Despite the simplicity of the model, good agreement with experimental data was obtained for a variety of drying conditions, especially in predicting the average moisture evolution and the drying time as well as the development of the temperature profiles in two types of softwood timbers.     

Viscometric study of extremely dilute macromolecular solutions: Critical concentration c and the intrinsic viscosity of the polystyrene through scaling laws. The values of the Huggins constant

A crossover is observed in the variation of the reduced viscosity, η_sp/c, as a function of the concentration, c, for polystyrene solutions in cyclohexane and dioxane. This crossover is attributed to the critical concentration c at which the macromolecular coils start to contact. The critical concentration c is related to the molecular weight and the intrinsic viscosity of the polystyrene through scaling laws. The values of the Huggins constant k' determined in the concentration regions below c (extremely dilute solutions) confirm the Peterson-Fixman theory.     

Modified stainless steel surfaces targeted to reduce fouling – Evaluation of fouling by milk components

Several stainless steel based surfaces with different properties were evaluated according to their fouling behaviour for different dairy products under different conditions. Surface properties were obtained by the following modification techniques: , and TiC ion implantation; diamond-like carbon (DLC) sputtering; DLC, DLC–Si–O and SiO_x, plasma enhanced chemical vapor Deposition (PECVD); autocatalytic Ni–P–PTFE and silica coating. Aqueous solutions that simulate milk (SMUF – simulated milk ultrafiltrate for the mineral components, β-lactoglobulin for the protein components and FMF – fouling model fluid for complex milk systems) were used to study the fouling behaviour during pasteurisation. Bacteriological deposition studies were also performed with two heat resistant strains of Bacillus. The experiments were carried out at laboratory scale for the evaluation of calcium phosphate and protein deposition, and at pilot scale for adhesion of bacteria and deposits from complex milk systems.

In all cases, the fouling behaviour was affected by the surface material, although in different ways for the deposition or the cleaning phases. For the non-microbiological deposits (calcium phosphate, whey protein and FMF milk-based product), the Ni–P–PTFE surface was the most promising one, since it generally promoted less deposit build up and, in all cases, was the easiest to clean. On the other hand, for bacterial adhesion, the most suitable surface was the ion implanted (TiC) surface, which also showed less spores after the cleaning process.