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Rice is an important food crop in China, fertilization measures significantly affect soil properties and ultimately change rice yield. Thus, examining the effects of long-term green manure cultivation on the rice yield and the driving factors on rice yield, plays a crucial role in maintaining food security. Based on the long-term green manure cultivation, the treatments included no fertilizer (CK), chemical fertilizer (NPK), chemical fertilizer + Chinese milk vetch (NPK + GM), chemical fertilizer + Chinese milk vetch + rice straws (NPK + GM + S), and chemical fertilizer + Chinese milk vetch + pig manure (NPK + GM + M) treatments. One-way repeated ANOVA was used to determine the effects of diverse fertilizer modes on temporal variations in rice yields. The redundancy analysis (RDA) was used to calculate the magnitudes of the effects of soil properties on rice yield. Compared with the CK treatment, four fertilizer treatments led to significantly increased double-season rice yields (116.40–124.49%), with no significant difference between four fertilizer treatments (p> 0.05). There were five soil properties accounting for 66.3% variation in rice yield (p< 0.05), with available potassium (AK) being the most influential factor (32.2% variation), whereas potential of hydrogen (pH), total nitrogen (TN), total phosphorus (TP), and soil organic carbon (SOC) accounted for 15.3%, 10.5%, 5.1%, and 3.2% variation in rice yield (p< 0.05), respectively. Thus, SOC, TN, TP, AK, and pH were major factors affecting the double-season rice yield of red paddy soil under long-term green manure cultivation. However, the results suggested that the effect of green manure on soil fertility is limited by the relatively large amount of chemical fertilizer. The results reported herein can not only increase soil fertility and improve the soil ecological environment, but also enhance and stabilize the yields of double-season rice grown in the red paddy soil of southern China.

Birnessite is one of the most important manganese oxides that can control the geochemical behaviors of pollutants or can be applied to form industrial products. Many studies have been conducted on the synthesis of hexagonal birnessite because different synthesis methods can affect the structural, morphological, and physicochemical properties of hexagonal birnessite. However, there are still some defects in these synthesis methods. Therefore, a new synthesis method that is rapid, simple, and low-cost was proposed in this study involving the reduction of KMnO4 by H2O2 in a H2SO4 solution without controlling the pH, temperature and pressure. Using a series of XRD, chemical composition, AOS, SSA, SEM, FTIR, and TGA analyses, Bir-H2O2 was found to have lower crystallinity than Bir-HCl. However, the AOS and SSA of Bir-H2O2 were 3.87 and 103 m2 g−1 higher than those of Bir-HCl, i.e., 3.70 and 22 m2 g−1, respectively. Moreover, both Bir-H2O2 and Bir-HCl had similar particle morphology and thermal stability; in addition, the maximum adsorption content of Pb2+ on Bir-H2O2 (∼3006 mmol kg−1) was ∼30% greater than that on Bir-HCl (∼2285 mmol kg−1) at pH 5.5; this indicated that the adsorption of Pb2+ on Bir-H2O2 was better and belonged to a pseudo-second-order model. All the abovementioned results indicate that Bir-H2O2 synthesized herein using the proposed synthesis method can have large application value.

Heterosis (or hybrid vigor) is a natural phenomenon whereby hybrid offspring of genetically diverse individuals display improved physical and functional characteristics relative to their parents. Heterosis has been increasingly applied in crop production for nearly a century, with the aim of developing more vigorous, higher yielding and better performing cultivars. In this review we present and compare three categories of crop heterosis utilization: intraspecific heterosis, intersubspecific heterosis and wide-hybridization heterosis, with particular focus on polyploid species. Different pollination-control systems used to breed for heterosis are also comparatively analyzed. Finally, we highlight problems involved in heterosis research and crop improvement. We aim to provide insight into best practices for amplifying heterosis potential.

The effect of inorganic ions and temperature on lead (Pb2 +) adsorption was evaluated on three acidic soils: yellow-brown soil (YBS), latosol soil (LS), and lateritic red soil (LRS). The results showed that the adsorption of Pb2 + in the presence of anions decreased in the order: SO42 − > NO3− = Cl−, while in the presence of cations, it reduced in the order: K+ > Ca2 +. Accordingly, the contamination of YBS, LS and LRS soils with Pb2 + was more noticeable when they contained more NO3−, Cl− and Ca2 + than SO42 − and K+. The distribution coefficient (Kd) of Pb2 + declined in the order: YBS > LS > LRS in the presence of anions. Adsorption and Kd values of Pb2 + were mainly dependent on ion types and altered surface properties caused by the adsorption and/or the formation of ion complexes. The Kd values enhanced slightly with increasing temperature up to 35 °C and then decreased at 45 °C. Based on the thermodynamic parameters, including the heat of reaction (ΔH), entropy change (ΔS) and the free energy change (ΔG), the adsorption process of Pb2 + on YBS, LS and LRS soils was endothermic and impetuous at low temperatures, whereas it was exothermic and non-spontaneous at high temperatures.

Phosphate rock (PR) has been widely and successfully used in immobilization of lead in contaminated soils. However, application of oxalic acid-activated PR (APR) in the immobilization of lead and particularly investigations about the lead form in the contaminated soils are limited. Exogenous lead (Pb) immobilization was studied by Tessier's sequential extraction procedures after applying raw PRs and oxalic acid APRs into the yellow cinnamon soil (S1) and latosol soil (S2) at four levels of 0 (CK), 50, 500, and 2000 mg P kg−1 soil. The PRs selected were Nanzhang PR (NPR) and Kaiyang PR (KPR), and their activation products were ANPR and AKPR. The results indicated that the content of exchangeable Pb in two soils decreased gradually with the rising PRs amount compared with the control, within 0–7.5 mg kg−1 in S1 and 0–64.1 mg kg−1 in S2. The content of carbonate-bound Pb changed marginally in S1 while increased substantially in S2 with the increase of PR amount; the change of Fe–Mn oxide-bound Pb content showed similar change as the carbonate-bound Pb and organic compound-bound Pb increased generally. The residue fraction of Pb changed a little for all treatments. To sum up, after applying the testing PRs in two soils, the content of exogenous exchangeable Pb decreased in all treatments and residual fraction augmented conversely in most treatments. Therefore, Pb had been immobilized effectively by PR in thetwo soils and a better fixation effect obtained in APR. ©2013 American Institute of Chemical Engineers Environ Prog, 33: 81–86, 2014

Constant looper height and small tension control is a basic characteristic of modern hot rolling mill. The control quality of looper system affects directly performances in the width and thickness of a product. A looper system has the features of nonlinearity, strong coupling, uncertainty, and multi-constraints. In this paper, a dynamic mathematical model of looper system is set up based on 1700ASP. In addition, multiple-input multiple-output (MIMO) space model at the vicinity of working point has been deduced. A new control strategy-fuzzy sliding mode control is introduced to decouple the system by using two filters to smooth control signal and to suppress output noise, respectively. Simulation results show that the algorithm is effective and has better control effect in resisting disturbance and weakening chattering after this system is decoupled.

Risk exists in the course of a project operation. Hence, selecting a good risk management strategy is essential for project success. In this paper, a two-phase evaluating method is proposed focusing on the characteristics of dynamic risk and multi attributes. Considering dynamic risk in a project, Markov process is used to evaluate risk in the first phase. And then, this paper explores how to select risk management strategy based on technique for order preference by similarity to ideal solution (TOPSIS) in view of completion time, cost, quality and success probability factors. Finally, a numerical example shows that this method is effective for decision making in project risk management.

A project consists of many subprojects with precedence. Subprojects' completion times are often uncertain due to many factors from inside and outside environment, which makes the project's completion time uncertain. In such case, the project cannot be delivered on time leading to tardiness risk. To address this uncertainty, we provide a risk measure-value at risk (VaR). A model with the objective to minimizing VaR is built to describe and quantify the tardiness risk. The proposed model is compared to Monte Carlo simulation. Comparison results show that this proposed method can replace Monte Carlo simulation in measuring tardiness risk.

Considering the features of coupling, multivariable, and nonlinearity in thickness and tension system for cold-rolling, this paper proposes a dynamic coupling model. Furthermore, a new compound decoupling control algorithm is designed based on diagonal recurrent neural network combined with PID(DRNN-PID) for decoupling control. Simulation results show the proposed algorithm has stronger adaptive tracking, faster response, and better anti-interference than PID. The performances can meet the requirement of practical rolling and effectively enhance the control accuracy of thickness and tension.

Heterosis (or hybrid vigor) refers to a natural phenomenon whereby hybrid offspring of genetically diverse individuals out-perform their parents in multiple traits including yield, adaptability and resistances to biotic and abiotic stressors. Innovations in technology and research continue to clarify the mechanisms underlying crop heterosis, however the intrinsic relationship between the biological basis of heterosis remain unclear. In this review, we aim to provide insight into the molecular genetic basis of heterosis by presenting recent advances in the 'omics' of heterosis and the role of non-coding regions, particularly in relation to energy-use efficiency. We propose that future research should focus on integrating the expanding datasets from different species and hybrid combinations, to mine key heterotic genes and unravel interactive 'omics' networks associated with heterosis. Improved understanding of heterosis and the biological basis for its manipulation in agriculture should help to streamline its use in enhancing crop productivity.

Lead (Pb) chemical fixation is an important environmental aspect for human health. Phosphate rocks (PRs) were utilized as an adsorbent to remove Pb from aqueous solution. Raw PRs and oxalic acid-activated PRs (APRs) were used to investigate the effect of chemical modification on the Pb-binding capacity in the pH range 2.0-5.0. The Pb adsorption rate of all treatments above pH 3.0 reached 90%. The Pb binding on PRs and APRs was pH-independent, except at pH 2.0 in activated treatments. The X-ray diffraction analysis confirmed that the raw PRs formed cerussite after reacting with the Pb solution, whereas the APRs formed pyromorphite. The Fourier Transform Infrared spectroscopy analysis indicated that carbonate (CO3(2-)) in raw PRs and phosphate (PO4(3)) groups in APRs played an important role in the Pb-binding process. After adsorption, anomalous block-shaped particles were observed by scanning electron microscopy with energy dispersive spectroscopy. The X-ray photoelectron spectroscopy data further indicated that both chemical and physical reactions occurred during the adsorption process according to the binding energy. Because of lower solubility of pyromorphite compared to cerussite, the APRs are more effective in immobilizing Pb than that of PRs.

To investigate the role and effects of the medium-grade phosphate rocks on Cu2+ removal in aqueous solution, three phosphate rocks (PRs) were selected from Hubei Province and the characteristics of Cu2+ removal were studied using batch experiment with phosphate rocks under different conditions in aqueous solution. The results showed: that the Cu2+ in aqueous solution was effectively removed by the PRs, the effects of Cu2+ removal were related to the composition of PRs, solution pH, ionic strength, Cu2+ concentration, coexisting metal ions such as Cd2+. With the increase of total content P of PRs, the pH of solution, the ionic strength, and the decrease of coexisting metal ions, the amount of Cu2+ adsorption in PRs increased. Further studies, using FTIR and XRD, have shown that Cu2+ combined with PRs on their surfaces, but did not form new compounds. These findings have an important impact on the rational development and application of phosphate rocks as adsorbents, and heavy metals treatment in wastewater in the future.

Virtual enterprise is becoming a production form of project organization. Minimizing risk in VE and ensuring success are the key problems to overcome. In this paper, in view of different risk effects from stochastic completion time choices of sub-projects , a risk programming model based on Markov process is presented. A genetic algorithm (GA) for this problem with embedded program evaluation and review technique (PERT) is developed to solve this problem. The performance of this algorithm is demonstrated by a case and the experimental problems of different sizes. The results of this trial demonstrate the real life capability of the algorithm.

The effect of phosphate rock (PR) on exogenous Pb fractions in yellow cinnamon soil (S1) and latosol soil (S2) were studied by Tessier’s sequential extraction procedures after PR was applied into the two soils at four levels of 0, 50, 500 and 2000 mg·kg−1. The results indicated that the content of exchangeable Pb in two soils decreased significantly with the rising of PR amount, which reached the minimum of 2.95 mg·kg−1 for yellow cinnamon soil and 3.57 mg·kg−1 for latosol soil under the treatment of 2000 mg P·kg−1 soil (PR3). Both of the residual fractions of Pb in the two soils reached the maximum under the treatment of 2000 mg P·kg−1 soil, 38.5 mg·kg−1 for yellow cinnamon soil and 66.1 mg·kg−1 for latosol soil. To sum up, the content of exogenous exchangeable Pb decreased and the residual fraction augmented conversely for both soils after the two soils being applied with testing PR. In conclusion, the result reflected that Pb had been immobilized effectively by PR in two tested soils.

With the emergence of global economy and in order to respond fast to the constantly changing market demand, virtual enterprises arise at this historic moment. Risk management of virtual enterprise draws attentions of researchers. This paper proposes a three-level model to deal with the dynamic risk of virtual enterprise, based on nonlinear integer programming, network analysis, and Markov process. The model focuses on project organization mode and dynamic features of risk in virtual enterprise. It helps to determine the completion time of each process with the objectives of maximizing the minimum completion probability of all processes under the constraints of project investment, customers' due dates, and process quality. Furthermore, an algorithm of integrated GA/CPM/Markov is designed to solve the problem and its efficiency is shown by instances analysis.

Generally, more than 120 ultrasonic sensors are necessary in a non-destructive testing (NDT) system for wide and thick steel plates. With the increase of the numbers of sensors, the system becomes more complex. It means that much higher automatization level is required in the parameters setting and much higher efficiency is demanded on data transmission in the network. This paper presents a novel ultrasonic NDT system based on the Ethernet network. The system accommodates 196 sensors and can detect plates with 4.8-meter width. The solution solves the data communication problem successfully. New technologies on hardware and software are introduced to improve the automatization level. All endeavors we have made ensure the new detection system can set parameters, adjust parameters automatically and complete the whole detection task automatically. In this paper, the network topology, network configuration and measures on real-time data transmission are also discussed. It is proved that the system is feasible in practice.

With the emergence of global market economy and in order to respond fast to the constantly changing market demand, virtual enterprises arise at this historic moment. Risk management of virtual enterprise draws attentions of researchers. This paper proposes a three-level programming model to deal with the dynamic risk of virtual enterprise, based on non-linear integer programming, network analysis, and Markov Process. The model focuses on project organization mode and dynamic features of risk in virtual enterprise. It helps to determine the completion time of each process with the objectives of maximizing the minimum completion probability of all processes under the constraints of project investment, customers' due dates, and process quality. Furthermore, an algorithm of integrated SA/CPM/Markov is designed to solve the problem and its efficacy is shown by instances.