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The comparative study of the transformation among sediment phosphorus (P) fractions in different lake types is a global issue in lake ecosystems. However, interactions between sediment P fractions, environmental factors, and microorganisms vary with the nutrient status of lakes. In this study, we combine sequential extraction and metagenomics sequencing to assess the characteristics of P fractions and transformation in sediments from different lake types in the Inner Mongolian section of the Yellow River Basin. We then further explore the response of relevant microbial and environmental drivers to P fraction transformation and bioavailability in sediments. The sediments of all three lakes exhibited strong exogenous pollution input characteristics, and higher nutritional conditions led to enhanced sediment P fraction transformation ability. The transformation capacity of the sediment P fractions also differed among the different lake types at the same latitudes, which is affected by many factors such as lake environmental factors and microorganisms. Different drivers reflected the mutual control of weakly adsorbed phosphorus (WA-P), potential active phosphorus (PA-P), Fe/Al-bound phosphorus (NaOH-P), and Ca-bound phosphorus (HCl-P) with the bio-directly available phosphorus (Bio-P). The transformation of NaOH-P in reducing environments can improve P bioavailability, while HCl-P is not easily bioavailable in weakly alkaline environments. There were significant differences in the bacterial community diversity and composition between the different lake types at the same latitude (p < 0.05), and the role of P fractions was stronger in the sediments of lakes with rich biodiversity than in poor biodiversity. Lake eutrophication recovery was somewhat hindered by the microbial interactions of P cycling and P fractions within the sediment. This study provides data and theoretical support for exploring the commonalities and differences among different lake types in the Inner Mongolian section of the Yellow River Basin. Besides, it is representative and typical for promoting the optimization of ecological security patterns in ecologically fragile watersheds. [ABSTRACT FROM AUTHOR]

Despite the superelastic deformation of NiTi has been documented and analyzed elaborately, its shape-memory behavior during stress-biased thermal cycling has not been thoroughly unveiled. This paper examines the evolution of transformation pattern in NiTi upon thermal cycling over a wide range of biasing stress. For the present shape-memory NiTi, both forward and reverse transformations proceed via the growth of localized deformation band (LDB) under low biasing stress (σ bias ≤ 150 MPa), while LDB only appears during forward transformation and reverse transformation is uniform under high biasing stress (σ bias ≥ 200 MPa). This is the first time that delocalization (conversion of deformation mode from localization to homogeneity) is observed during stress-biased thermal cycling. We clarify that the intrinsic undercooling/overheating of martensitic transformation results in unstable thermomechanical response, and it is the origin of localization in shape-memory NiTi. It is found that transformation-induced plasticity (TRIP), which is dominated by dislocation slip and deformation twining, not only causes irreversibility in the present shape-memory NiTi but also leads to delocalization through stabilization of intrinsic thermomechanical response of reverse transformation. • The first time that delocalization is observed under stress-biased thermal cycling of shape-memory NiTi. • TRIP dominated by dislocations and deformation twins causes irreversibility in the present shape-memory NiTi. • The intrinsic undercooling/overheating of martensitic transformation is the origin of localization in shape-memory NiTi. • Stabilization of intrinsic thermomechanical response by TRIP leads to delocalization during stress-biased thermal cycling. [ABSTRACT FROM AUTHOR]

Based on thin plate tensile tests of super-elastic NiTi alloy at different temperatures, a trilinear elasto-plastic constitutive model was adopted and the effect of latent heat of phase transformation on the temperature rise was considered through an equivalent method of thermo-physical constants.The transformation pattern evolutions were simulated by finite element software ABAQUS, and the rate-dependent mechanisms were also revealed. The simulated results show that the stress-induced martensitic transformation occurs under tensile loading, which macroscopically exhibits as the initiation, propagation and merging of local transformation bands; due to the release of latent heat, the initiation of transformation bands is accompanied by local temperature rise, and peak temperature rise is closely related to the loading strain rate; the local transformation bands are at a certain angle to the loading direction, which is about 50°-65°; with the increase of loading rate, the sample is changed from the isothermal state to the adiabatic one, the transformation stress and local temperature rise increase then. Therefore, the transformation tends to occur in the low temperature region, which results in an increasing number of transformation bands. The simulated transformation patterns and temperature field evolutions of super-elastic NiTi alloy at different strain rates are in good agreement with the corresponding experimental results, which provide a reference for clarifying the evolution of transformation localization of the alloy.

Model transformation plays an important role in developing software systems using the model-driven engineering paradigm. Examples of applications of model transformation include forward engineering, reverse engineering of code into models, and refactoring. Poor-quality model transformation code is costly and hard to maintain. There is a need to develop techniques and tools that can support transformation engineers in designing high-quality model transformations. The goal of this paper is to present a process, called MUPPIT (method for using proper patterns in model transformations), which can be used by transformation engineers to improve the quality of model transformations by detecting anti-patterns in the transformations and automatically applying pattern solutions. MUPPIT consists of four phases: (1) identifying a transformation anti-pattern, (2) proposing a pattern-solution, (3) applying the pattern-solution, and (4) evaluating the transformation model. MUPPIT takes a transformation design model (TDM), which is a representation of the given transformation, to search for the presence of an anti-pattern of interest. If found, MUPPIT proposes a pattern solution from a catalogue of patterns to the transformation engineer. The application of the pattern solution results in the restructuring of the TDM. While MUPPIT, as a process, is independent of any transformation language and transformation engineering framework, we have implemented an instance of it as a tool using transML and MeTAGeM, which support exogenous transformations using rule-based transformation and OCL-based languages such as ATL and ETL. We evaluate MUPPIT through a number of case studies in which we show how MUPPIT can detect four anti-patterns and propose the corresponding pattern solutions. We also evaluate MUPPIT by collecting a number of metrics to assess the quality of the resulting transformations. The results show that MUPPIT optimizes the transformations by improving reusability, modularity, simplicity, and maintainability, as well as decreasing the complexity. MUPPIT can help transformation engineers to produce high-quality transformations using a pattern-based approach. An immediate future direction would be to experiment with more anti-patterns and pattern solutions. Moreover, we need to implement MUPPIT using other transformation engineering frameworks. [ABSTRACT FROM AUTHOR]

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To describe the grain size dependence and rate dependence of superelastic NiTi, a constitutive model involving intrinsic material instability and thermomechanical coupling is proposed and implemented implicitly into finite element software. The material is regarded as a mixing of transformable phase and non-transformable phase. The thermodynamic driving force for martensitic transformation and the heat equilibrium equation are deduced in the framework of irreversible thermodynamics. The global thermomechanical response, i.e. stress–strain curve, and local thermomechanical response, i.e. strain and temperature profiles, are simulated. If the grain size is above 68 nm, NiTi is characterized with Lüders like deformation associated with strong thermomechanical coupling. If the grain size is 42 nm and 27 nm, Lüders like deformation does not take place because Considere criterion is not fulfilled. Strain localization is visible owing to the collective effect of thermomechanical coupling and temperature inhomogeneity. If the grain size is 10 nm, thermomechanical coupling is suppressed and NiTi deforms homogeneously. [ABSTRACT FROM AUTHOR]

• 49 TPs including 14 new TPs were identified by molecular networking strategy. • Five transformation patterns for sulfonamides in wastewater were summarized. • The role of formylation as the dominant pathway for sulfonamides was firstly reported. • The same active site may cause the specific transformation patterns of sulfonamides in wastewater. Biotransformation of emerging contaminants (ECs) is of importance in various natural and engineered systems to eliminate the adverse effects of ECs toward organisms. In wastewater, structurally similar ECs may transform through similar reactions triggered by common enzymes. However, the transformation pattern for them was scarcely studied. To fill the research gaps, five sulfonamides were chosen as the targeted ECs with similar structure to explore the transformation pattern in wastewater biological treatment experiments at lab scale. Through molecular networking based nontarget screening, 45 transformation products (TPs) of sulfonamides were identified and 14 of them were newly found. On the basis, five specific transformation patterns were summarized for sulfonamides by transformation pathways comparing, reaction frequency analyzing and dominant TPs comparing. Results suggested that pterin-chelation and formylation (dominant transformation pathway) and acetylation, methylation and deamination reactions were commonly occurred for sulfonamides in wastewater. Among them, the role of formylation as the dominant transformation pathway for sulfonamides transformed in wastewater was firstly reported in present study. Subsequent frontier molecular orbital calculation suggested the active site of amino (N 1 H 2 -) may contribute the specific transformation pattern of sulfonamides. Present study reveals the specific transformation pattern of sulfonamides from the aspect of TPs and transformation pathways. In the future, knowledge on the specific transformation pattern can be used to regulate and enhance the removal of a class of ECs with similar structure rather than just one of ECs. [Display omitted] [ABSTRACT FROM AUTHOR]

Recent studies showed that sulfidated nano zerovalent iron (S-nZVI) is a better alternative to non-sulfidated nano zerovalent iron (NS-nZVI) commonly used for contaminated site remediation. However, its reactivity with different halogenated pollutants such as tetrabromobisphenol A (TBBPA) remains unclear. In this study, we explored the reductive transformation of TBBPA by S-nZVI and compared it with that by NS-nZVI. The results showed that over 90% of the initial TBBPA (20 mg L −1 ) was transformed by S-nZVI within 24 h of reaction, which was 1.65 times as high as that for NS-nZVI. The TBBPA transformation by S-nZVI was well described by a pseudo-first-order kinetic model, whilst that by NS-nZVI was well fitted by a three-parameter single exponential decay model. After 11 weeks of aging, S-nZVI was still able to transform up to 56% of the initial TBBPA within 24 h of reaction; by contrast, the two-week aged NS-nZVI lost more than 95% of its original capacity to transform TBBPA. Moreover, S-nZVI showed only an approximately 20% decrease in its capacity to transform TBBPA in the seventh cycle, while NS-nZVI was no longer able to transform TBBPA in the fourth cycle. XPS analysis suggested the formation of FeS layer on S-nZVI surface and electrochemical analysis revealed an elevated electron transfer capacity of S-nZVI, which were likely responsible for the superior performances of S-nZVI in TBBPA transformation. While the transformation rate of TBBPA by S-nZVI decreased with increasing initial concentration of TBBPA, it showed an increasing trend with increasing S/Fe ratio and initial concentration of S-nZVI. The study indicated that S-nZVI has the potential to be a promising alternative to NS-nZVI for remediation of TBBPA-contaminated aquatic environments. [ABSTRACT FROM AUTHOR]

Service-oriented computing (SOC) is the computing paradigm that utilizes services as a fundamental building block. Services are self-describing, open components intended to support composition of distributed applications. Currently, Web services provide a standard-based realization of SOC due to: (1) the machine-readable format (XML) of their functional and nonfunctional specifications, and (2) their messaging protocols built on top of the Internet. However, how to methodologically identify, specify, design, deploy and manage a sound and complete set of Web services to move to a service-oriented architecture (SOA) is still an issue. This paper describes a process for reverse engineering relational database applications architecture into SOA architecture, where SQL statements are insulated from the applications, factored, implemented, and registered as Web services to be discovered, selected, and reused in composing e-business solutions. The process is based on two types of design patterns: schema transformation pattern and CRUD operations pattern. First, the schema transformation pattern allows an identification of the services. Then the CRUD operations pattern allows a specification of the abstract part of the identified services, namely their port types. This process is implemented as a CASE tool, which assists analysts specifying services that implement common, reusable, basic business logic and data manipulation. [ABSTRACT FROM AUTHOR]

Based on the characteristic of ‘one river one oasis’ in the arid areas, the Yerqiang River Basin, which is the largest irrigated area of Xinjiang, is taken as an example in this paper, and the regional water circulation pattern is investigated through the analysis of 60 groups of isotope data in the basin. From the phreatic evaporation data analysis of different soils, we study the law of phreatic evaporation, complete the research of the main consumption path of the groundwater, and improve the assessment precision of water resources. The transformation mount of regional water resources are predicted by calculation, which provides a scientific basis for water resources assessment and allocation in arid regions, and offers a new method for the study of regional water circulation patterns. [ABSTRACT FROM AUTHOR]

In this paper, multiple cases of cyclic loadings on superelastic NiTi are studied experimentally and then numerically by means of finite element simulations. A novel constitutive framework is proposed to account for cyclic response of superelastic NiTi shape memory alloy. Martensitic transformation and degradation of mechanical properties are taken into consideration. The mechanical instability is involved in the model to reproduce transformation pattern under primarily tensile stress states. The Helmholtz free energy of the representative volume element is derived and the evolutions of internal variables are obtained keeping to dissipative inequality. Based on backward Euler integration scheme, the model is implemented implicitly into a finite element code. By comparing the simulation results with the experimental ones, it is verified that the proposed approach captures the features of the cyclic response and the associated strain pattern reasonably. Image, graphical abstract [ABSTRACT FROM AUTHOR]