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This study investigates the utility of plant δ¹3C natural labeling in predicting the impacts of environmental shifts on carbon cycling within ecosystems, particularly focusing on paddy fields treated with maize (Zea maysL.) residues and biochar. Specifically, it examines how soil δ¹3C and the sources of soil organic carbon (SOC), respond in paddy fields (which cultivate C3plants like rice) when amended with maize residues, maize biochar, and silica‐enriched biochar (derived from C4plants). Conducted in the Fuzhou paddy fields, the experiment included control groups and treatment groups with maize residue (4 t ha⁻¹), maize biochar (4 t ha⁻¹), and silicon‐modified maize biochar (4 t ha⁻¹) during both the early and late rice growth periods. The results indicate that all soil treatments increased soil δ¹3C. The application of maize residues notably affected the δ¹3C of the upper soil profile (0–15 cm) differently from the deeper layers (15–30 cm), and it increased soil organic C more than biochar or silicon‐modified maize biochar. Soil available P (AP) and pH emerged as significant factors linking δ¹3C, influencing rice yield through changes in soil physicochemical properties. Unlike maize residues, which reduced rice yields, applications of biochar and silicon‐modified maize biochar increased rice yields. The latter, which was particularly effective in lowering SOC decomposition rates and addressing rice's silica needs, emerged as the preferred option. The study highlights maize biochar and silicon‐modified maize biochar as sustainable alternatives to maize residues for rice cultivation, enhancing soil fertility, carbon pool stability, and yields. New management of crop residues to improve crop soil quality in paddy fields is studied.New management of crop residues to improve rice yield is studied.The suitability of use of δ13C labeling methods for this type of research is determined.The relationship between diverse soil physicochemical properties with changes in soil organic carbon contents and quality is studied.The use of excessive industrial fertilizers should be avoided.

Super 13Cr, as an economy stainless steel (SS) for oil country tubular goods, needs stable corrosion resistance in high-pressure and high-temperature (HPHT) downhole medium. Severe plastic deformation (SPD) are the surface modification technology to improve mechanical properties, fatigue behavior and corrosion resistance of metals, and shot peening (SP) has been the most widely used SPD process. However, there are quite limited studies about the microsutructure evolution, residual stress, and high-temperature corrosion behavior of SP-treated martensitic SS. In this study, super 13Cr martensitic SS was treated by SP with various air pressures and nozzle speeds. The surface characteristics and high-temperature corrosion behaviour in 3.17 mol/L K2HPO4solution were investigated through finite element model analysis, characterization of residual stress and microstructure, as well as electrochemical and stress corrosion cracking (SCC) tests at 160 °C and 10 MPa. The results showed that SP-treated super 13Cr could generate high-level compressive residual stress and SPD microstucture, including nano-sized equiaxed grains, gradient lamellar structure and fragmented carbides. Increasing air pressure contributed to achieve uniform nanocrystalline, but tended to generate high dislocation density and surface defects. The improving effect of SP treatment at low air pressure of 0.15 MPa on passivation ability was limited, and high air pressure adversely impacted corrosion resistance. SP-treated specimens showed high SCC susceptibility, due to the introduction of more surface defects, high angle grain boundaries, and dislocations.

A detailed understanding of the distribution and potential of natural gas hydrate (NGHs) resources is crucial to fostering the industrialization of those resources in the South China Sea, where NGHs are abundant. In this study, this study analyzed the applicability of resource evaluation methods, including the volumetric, genesis, and analogy methods, and estimated NGHs resource potential in the South China Sea by using scientific resource evaluation methods based on the factors controlling the geological accumulation and the reservoir characteristics of NGHs. Furthermore, this study compared the evaluation results of NGHs resource evaluations in representative worldwise sea areas via rational analysis. The results of this study are as follows: (1) The gas hydrate accumulation in the South China Sea is characterized by multiple sources of gas supply, multi-channel migration, and extensive accumulation, which are significantly different from those of oil and gas and other unconventional resources. (2) The evaluation of gas hydrate resources in the South China Sea is a highly targeted, stratified, and multidisciplinary evaluation of geological resources under the framework of a multi-type gas hydrate resource evaluation system and focuses on the comprehensive utilization of multi-source heterogeneous data. (3) Global NGHs resources is nx 1015m3, while the NGHs resources in the South China Sea are estimated to be 1013m3, which is comparable to the abundance of typical marine NGHs deposits in other parts of the world. In the South China Sea, the NGHs resources have a broad prospect and provide a substantial resource base for production tests and industrialization of NGHs.

A mechanistic modelling of the adsorption processes onto individual minerals presenting in the near- and far-fields can greatly enhance the credibility of long-term safety assessments of granite-based geological repositories. In this study, the titration and U(VI) adsorption characteristics of chlorite, one of the major minerals of rock fractures, have been studied. Potentiometric titration curves at two ionic strengths (0.1 and 0.4 mol/L NaCl) are successfully interpreted by considering protonation/deprotonation reactions on generic edge sites (≡SOH) in the framework of a non-electrostatic surface complexation model (SCM). The adsorption of U(VI) on chlorite was reached after 24 h, the adsorption kinetics can be described by a pseudo-second-order model. A non-electrostatic SCM with three surface complexes (≡SOUO2+, ≡SO(UO2)3(OH)5and ≡SO(UO2)3(OH)72−) was set up based on pH edges of U(VI) at adsorption equilibrium in the absence of CO2. Additional, experimental data measured as a function of U(VI) concentration, solid-to-liquid ratio and carbonate concentration were well reproduced by the proposed model. Finally, parallel experiments were conducted using X-ray photoelectron spectroscopy (XPS) to analyze the variation of U(VI) surface species speciation at different pH values. The good agreement between SCM prediction and XPS analysis demonstrates the reliability of the model in predicting and quantifying the radionuclides retention by chlorite.

It has been hypothesized that trap charge plays an important role in PMOS (positive-channel metal oxide semiconductor) device reliability. By using electron holography, trap charge in a spacer oxide was observed to cause an inversion of junction in an un-stressed PMOS device prepared using a Ga+ focused ion beam (FIB). Through 400°C annealing for 10 min in vacuum, trap charge in the spacer oxide dispersed and the junction recovered. Technology computer-aided design (TCAD) simulation was used to confirm the positive trap charge effect on the junction. Furthermore, the simulation showed that a low concentration of positive trap charge at the Si/SiO2interface under the spacer led to a higher tunneling current due to an abrupt junction near the Si surface through a very localized junction inversion.

This article studies the finite-time stabilization and finite-time H∞control problems for a class of Takagi–Sugeno fuzzy singular systems and proposes a finite-time H∞fuzzy controller to enable the system to cope with external disturbances, and the closed-loop system state converges to the equilibrium point. Before designing the controller, impulse controllability of the Takagi–Sugeno fuzzy singular system is discussed. Then, a finite-time H∞fuzzy controller is designed, and the finite-time stabilization conditions of the Takagi–Sugeno fuzzy singular system are expressed by linear matrix inequality. Finally, the simulation outcomes of a nonlinear singular system demonstrate that the designed controller has a good suppression effect on external disturbances, and the closed-loop system state converges to the equilibrium point in finite-time T and remains at the equilibrium point after T.

Antibiotic resistance caused by biofilm formation is a clinical challenge. Nitric oxide (NO) can effectively disperse a mature biofilm and can also synergistically influence the level of cyclic diguanylate (c-di-GMP), a universal secondary messenger that plays an important role in biofilm formation in bacteria. Based on our previous finding that c-di-GMP G-quadruplex inducers are effective biofilm formation inhibitors, we designed and synthesized a c-di-GMP G-quadruplex inducer-NO donor conjugate (A11@NO) as a bifunctional antibiofilm agent after obtaining the c-di-GMP G-quadruplex inducer (A11), which has an amino group capable of binding to a nitroso group (NO donor). The conjugate A11@NOshowed better biofilm inhibition efficiency than A11, and it can also eradicate mature biofilm. Additionally, it exhibited good antimicrobial synergism against Pseudomonas aeruginosaand helped elevate the bactericidal efficiency of tobramycin against biofilm-formed bacteria. In combination with tobramycin, A11@NOalso improved the survival rate of Caenorhabditis elegansin a hyperbiofilm environment.

Intuitionistic fuzzy (IF) set theory combined with twin support vector machines (TSVM) has shown highly advantageous performance in robust and fast classification. However, the existing methods have some inherent flaws: 1) The inaccurate confidence caused by the single-center-based IF strategy degrades the classification performance of the model. 2) The nonmembership degree is time-consuming and the threshold is difficult to determine, as it depends on sample's local neighborhood set. 3) Recent theoretical studies have demonstrated that optimizing the margin distribution achieve better generalization performance than maximizing the minimum margin in SVM-based models (SVMs). In view of the aforementioned shortcomings, we propose a novel dual-center-based IF (DC-IF) function, and introduce the margin distribution into IFTSVM, forming a DC-IF twin bounded large margin distribution machines (DC-IFTBLDM). Initially, the DC-IF strategy references the contribution of one sample to both categories, which is time efficient and more accurately reflects the credibility of the samples. Moreover, the margin mean and variance are used to optimize the margin distribution, and a regularization term is utilized to minimize structural risk. Therefore, DC-IFTBLDM has a good performance in noise immunity and classification capability. Comparative experiments based on synthetic datasets, UCI benchmark datasets, and datasets with different noise ratios verify the effectiveness of the proposed model. The parameter sensitivity analysis further proves the high accuracy and stability of DC-IFTBLDM.

As a prerequisite and a guarantee for safe and efficient natural gas hydrates (NGHs) exploitation, it is imperative to effectively determine the mechanical properties of NGHs reservoirs and clarify the law of the change in the mechanical properties with the dissociation of NGHs during NGHs production tests by depressurization. Based on the development of Japan’s two offshore NGHs production tests in vertical wells, this study innovatively proposed a new subsea communication technology—accurate directional connection using a wet-mate connector. This helps to overcome the technical barrier to the communication between the upper and lower completion of offshore wells. Using this new communication technology, this study explored and designed a mechanical monitoring scheme for lower completion (sand screens). This scheme can be used to monitor the tensile stress and radial compressive stress of sand screens caused by NGHs reservoirs in real time, thus promoting the technical development for the rapid assessment and real-time feedback of the in-situmechanical response of NGHs reservoirs during offshore NGHs production tests by depressurization.

China's urban bicycle-sharing is crucial in promoting carbon mitigation owing to its inherent green and low-carbon intention. However, the real carbon mitigation potential is overshadowed by the reality of regional differences and associated environmental and social problems; therefore, an objective evaluation is urgent. Based on the SE-SBM model considering undesirable outputs, this paper combines the Malmquist index to measure carbon mitigation efficiency. The study found that the four major categories of cities show continuous W-shaped fluctuations of decreasing and then increasing, and only ten cities have higher relative efficiency, with 13.89% of DMU being effective. The carbon reduction performance shows a regional difference pattern of west-middle-east stepped growth, and the evolutionary characteristics of different types of cities have noticeable spatial and temporal inertia and spatial aggregation characteristics. Additionally, the area positioning for carbon reduction was determined by a three-dimensional matrix analysis, and Tobit regression was used to identify the significant variables influencing the effectiveness of carbon reduction.

The aggregation of nano-aluminum powder seriously hinders the energy release of aluminized explosives. This study developed a strategy of using the droplet microfluidic technology to prepare HMX/15 ​wt% n-Al/2 ​wt% (NC and F2604) high-energy microspheres and systematically studied the effects of different binders on the morphology (i.e., roundness) and dispersion properties of microspheres. Moreover, it investigated the thermal decomposition, mechanical sensitivity, and combustion performance using TG, differential scanning calorimetry (DSC), and mechanical sensitivity and combustion experiments. Results show that all the prepared microspheres are regular spherical and enjoy excellent dispersion and high packing density. Using NC as a binder offers more advantages, including favorable roundness, angle of repose, and bulk density values, which were found to be 0.921, 27.1°, and 0.723 ​g·cm-3, respectively. Using fluorine rubber (F2604) as a binder promotes the oxidation of nano-aluminum and delays the decomposition of HMX. Meanwhile, the microsphere structure can effectively reduce the sensitivity, and the use of F2604 as a binder can significantly improve the safety performance. As a result, the obtained aluminum-containing explosives have impact and friction sensitivities of 60 ​J and 220 ​N, respectively. In addition, compared to physically mixed samples, the microsphere samples have significantly improved combustion performance, more intense combustion reactions, and a shorter burning time, all of which are attributed to their uniform structures and the interactions between components. These results indicate that the strategy using the droplet microfluidic technology provides a new method for preparing high quality aluminized explosives efficiently and safely.

Thermal-responsive hydrogel actuators have aroused a wide scope of research interest and have been extensively studied. However, their actuating behaviors are usually monotonous due to their unchangeable shapes and structures. Here, we report thermal-responsive poly(isopropylacrylamide-co-2-(dimethylamino)ethyl methacrylate)/alginate hydrogels with programmable external shapes and internal actuating trajectories. The volume phase transition temperatures of the resulting hydrogels can be tuned in a wide temperature range from 32 to above 50 °C by adjusting the monomer composition. While the formation and photo-dissociation of Fe3+–carboxylate tri-coordinates within the entire hydrogel network enable photo-responsive shape memory property, the insufficient dissociation of the tri-coordinates along the irradiation path gives rise to gradient crosslinking for realizing thermal-responsive actuation. Controlling the evolution of the gradient structure facilitates the regulation of the actuating amplitude. Furthermore, we show that the combination of these two types of shape-changing functionalities leads to more flexible and intricate shape-changing behaviors. One interesting application, a programmable hook with changeable actuating behaviors for lifting different objects with specific shapes, is also demonstrated. The proposed strategy can be extended to other types of actuating hydrogels with more advanced actuating behaviors.

Walnut (Juglans regiaL.) is a good source of lipids and polyunsaturated fatty acids (PUFAs). In order to explore the biosynthesis molecular mechanism of oil accumulation and fatty acid (FA) synthesis in walnut, the samples at different development periods of three walnut cultivars, ‘Zhipi’ (ZP), ‘Xinwu 417’ (W417) and ‘Xinwen 81’ (W81) were collected for transcriptomic analysis. The analysis of oil accumulation and FA profiles showed that the oil content in mature walnut kernel was nearly 70 %, and over 90 % of FAs were PUFAs. We identified 126 candidate genes including 64 genes for FA de novosynthesis, 45 genes for triacylglycerol assembly, and 17 genes for oil bodies involved in lipid biosynthesis by RNA-sequencing. Ten key enzymes including ACCase, LACS6, LACS8, SAD, FAD2, FAD3, LPAAT1, DGAT2, PDAT2, and PLC encoded by 19 genes were highly associated with lipid biosynthesis. Quantitative PCR analysis further validated 9 important genes, and the results were well consistent with our transcriptomic data. Finally, 5 important transcription factors including WRI1, ABI3, FUS3, PKL and VAL1 were identified, and their main regulatory genes might contain ACCase, KASⅡ, LACS, FAD3 and LPAAT which were determined through correlation analysis of expression levels for 27 walnut samples. These findings will provide a comprehensive understanding and valuable information on the genetic engineering and molecular breeding in walnut.

To obtain the characteristics of the gas hydrate reservoirs at GMGS3-W19, extensive geophysical logging data and cores were analyzed to assess the reservoir properties. Sediment porosities were estimated from density, neutron, and nuclear magnetic resonance (NMR) logs. Both the resistivity and NMR logs were used to calculate gas hydrate saturations, the Simandoux model was employed to eliminate the effects of high clay content determined based on the ECS and core data. The density porosity was closely in agreement with the core-derived porosity, and the neutron porosity was higher while the NMR porosity was lower than the density porosity of sediments without hydrates. The resistivity log has higher vertical resolution than the NMR log and thus is more favorable for assessing gas hydrate saturation with strong heterogeneity. For the gas hydrate reservoirs at GMGS3-W19, the porosity, gas hydrate saturation and free gas saturation was 52.7%, 42.7% and 10%, on average, respectively. The various logs provide different methods for the comprehensive evaluation of hydrate reservoir, which supports the selection of candidate site for gas hydrate production testing.

Evaluating velocity-porosity relationships of hydrate-bearing marine sediments is essential for characterizing natural gas hydrates below seafloor as either a potential energy resource or geohazards risks. Four sites had cored using pressure and non-pressure methods during the gas hydrates drilling project (GMGS4) expedition at Shenhu Area, north slope of the South China Sea. Sediments were cored above, below, and through the gas-hydrate-bearing zone guided with logging-while-drilling analysis results. Gamma density and P-wave velocity were measured in each pressure core before subsampling. Methane hydrates volumes in total 62 samples were calculated from the moles of excess methane collected during depressurization experiments. The concentration of methane hydrates ranged from 0.3% to 32.3%. The concentrations of pore fluid (25.44% to 68.82%) and sediments (23.63% to 54.28%) were calculated from the gamma density. The regression models of P-wave velocity were derived and compared with a global empirical equation derived from shallow, unconsolidated sediments data. The results were close to the global trend when the fluid concentration is larger than the critical porosity. It is concluded that the dominant factor of P-wave velocity in hydrate-bearing marine sediments is the presence of the hydrate. Methane hydrates can reduce the fluid concentration by discharging the pore fluid and occupying the original pore space of sediments after its formation.

Various factors controlling the accumulation of natural gas hydrates (NGHs) form various enrichment and accumulation modes through organic combination. This study mainly analyzes the geological and geophysical characteristics of the NGHs occurrence in the uplifts and their slope zones within the deep-water area in the Qiongdongnan (QDN) Basin (also referred to as the study area). Furthermore, it investigates the dominant governing factors and models of NGHs migration and accumulation in the study area. The results are as follows. (1) The uplifts and their slope zones in the study area lie in the dominant pressure-relief direction of fluids in central hydrocarbon-rich sags in the area, which provide sufficient gas sources for the NGHs accumulation and enrichment through pathways such as gas chimneys and faults. (2) The top and flanks of gas chimneys below the bottom simulating reflectors (BSRs) show high-amplitude seismic reflections and pronounced transverse charging of free gas, indicating the occurrence of a large amount of gas accumulation at the heights of the uplifts. (3) Chimneys, faults, and high-porosity and high-permeability strata, which connect the gas hydrate temperature-pressure stability zones (GHSZs) with thermogenic gas and biogenic gas, form the main hydrate migration system. (4) The reservoir system in the study area comprises sedimentary interlayers consisting of mass transport deposits (MTDs) and turbidites. In addition, the reservoir system has developed fissure- and pore-filling types of hydrates in the pathways. The above well-matched controlling factors of hydrate accumulation enable the uplifts and their slope zones in the study area to become the favorable targets of NGHs exploration.

Byline: Victor Chu, Jin-qiang Kuang, Amy McGinna, Adel Giaid, Stephen Korkola, Ray C.-J. Chiu Abstract: Background: Angiogenesis is the proposed mechanism of transmyocardial revascularization. We evaluated mechanical transmyocardial revascularization in a chronically ischemic porcine model by measuring myocardial angiogenic response. Methods: Ameroid constrictors were implanted 6 weeks before mechanical transmyocardial revascularization. Group I (n = 5) and group II (n = 3) animals received 30 punctures with an 18-gauge needle and samples were harvested at 1 and 4 weeks, respectively, after the operation. Group III (n = 5) had sternotomy only and served as the control group. Myocardial samples were immunohistochemically stained for vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and transforming growth factor [beta] (TGF-[beta]) using specific antibodies. Growth factor expression was quantified by means of computer-assisted morphometry. Vascular density was assessed by immunohistochemical stain for VEGF and factor VIII. Results: Compared with group III, increased angiogenic factor levels were found in group I (VEGF 0.47 [+ or -] 0.03 mm.sup.2 vs 0.05 [+ or -] 0.05 mm.sup.2, P = .000; bFGF 0.67 [+ or -] 0.14 mm.sup.2 vs 0.03 [+ or -] 0.03 mm.sup.2, P = .000; TGF-[beta] 1.40 [+ or -] 0.18 mm.sup.2 vs 0.09 [+ or -] 0.06 mm.sup.2, P = 0.000), and in group II (VEGF 0.34 [+ or -] 0.06 mm.sup.2 vs 0.05 [+ or -] 0.05 mm.sup.2, P = .003; bFGF 0.06 [+ or -] 0.02 mm.sup.2 vs 0.03 [+ or -] 0.03 mm.sup.2, P = .135; TGF-[beta] 0.28 [+ or -] 0.09 mm.sup.2 vs 0.09 [+ or -] 0.06 mm.sup.2, P = .042). Vascular densities after mechanical transmyocardial revascularization were also increased (group I, VEGF stain 8.1 [+ or -] 0.6 vs 1.1 [+ or -] 0.5, P = .000; factor VIII stain 5.1 [+ or -] 2.7 vs 0.4 [+ or -] 0.3, P = .018; group II, VEGF stain 1.9 [+ or -] 0.5 vs 1.1 [+ or -] 0.5, P = 0.107; factor VIII stain 2.3 [+ or -] 0.4 vs 0.4 [+ or -] 0.3, P = .004). Conclusions: Mechanical transmyocardial revascularization is associated with increased angiogenic factor expression and concomitant neovascularization at up to 4 weeks. These changes are indistinguishable from those of laser transmyocardial revascularization. Myocardial perfusion studies are needed to establish the functional significance of these angiogenic changes. (J Thorac Cardiovasc Surg 1999; 118:849-56) Author Affiliation: From the Division of Cardiothoracic Surgery.sup.a and the Department of Pathology, McGill University,.sup.b Montreal, Quebec, Canada Article History: Received 19 March 1999; Revised 4 May 1999; Revised 8 July 1999; Accepted 13 July 1999 Article Note: (footnote) [star] Read at the Seventy-ninth Annual Meeting of The American Association for Thoracic Surgery, New Orleans, La, April 18-21, 1999., [star][star] Address for reprints: Ray C.-J. Chiu, MD, Room C9.169, Montreal General Hospital, 1650 Cedar Ave, Montreal, Quebec, H3G 1A4, Canada (E-mail: mdiu@musica.mcgill.ca )., a 0022-5223/99 $8.00 + 0 12/6/101413

China is considering Beishan granitic formation (Gansu Province, China) as the site for high-level radioactive waste (HLW) repositories. Thus, it is crucial to understand the transport behavior of radionuclide in Beishan granitic media under disposal conditions. In this context, the co-transport of U(VI) (as the representative of radionuclides) and bentonite colloid (BC, from erosion of compacted bentonite) in particulate Beishan granite was studied as a function of important in-situfactors, such as BC concentration, ionic strength, pH and flow rate. We found that the increase of BC concentration (BC = 240–480 mg/L) did not affect the transport of individual BC, whereas it significantly facilitated the transport of U(VI). The increase of ionic strength (I= 0.001–0.01 M NaCl) or decrease of pH (pH = 7.50–5.40) obviously inhibited the BC transport, where these inhibiting effects were relatively slight for the transport of U(VI). The increase of flow rate significantly facilitated both the transport of BC and U(VI). Finally, a two-site kinetic attachment/detachment model was applied to describe the breakthrough curves of individual and co-transport of BC. The experimental and modeling results of this study have a significant implication on the safety assessment of HLW repositories built in granitic formation.

Low-temperature silicon nitride (SiNx) films deposited by plasma-enhanced chemical vapor deposition (PECVD) have huge application potential in the flexible display. However, the applicability of SiNxlargely depends on the film’s general properties, including flexibility, deposition rate, residual stress, elastic modulus, fracture strain, dielectric constant, refraction index, etc. Process optimization towards specific application by conventional experiment design needs lots of work due to the interaction of muti quality and process parameters. Therefore, an efficient global optimization approach for the process technology was proposed based on the Taguchi orthogonal experiment method considering muti-factor muti-responses. First of all, the Taguchi orthogonal experiment design and analysis was used to rank the influences of main process parameters on the quality characteristics, including radio frequency (RF) power, pressure, silane flow rate, ammonia flow rate and nitrogen flow rate. Then, the global optimization approach was carried out utilizing the multi-response optimizer considering the combination target of film formation rate, residual stress, dielectric constant, elastic modulus, fracture strain, refractive index. Finally, the optimal solution of the SiNxfilm was finally obtained and verified.

As a hazardous waste, secondary aluminum dross (SAD) has troubled the aluminum industry for many years. The inefficient and incomplete hydrolysis of active aluminum components such as AlN, Al4C3, Al2S3, AlP in SAD was the main obstacle, which can react with water or even humid air to release toxic, harmful, flammable and odorous gases such as NH3, CH4, H2S, and PH3to the environment. In this study, a novel approach to prepare adsorbent was proposed by the deep hydrolysis of active aluminum components from SAD with the aid of grinding activation. High-energy grinding could increase the hydrolysis rate of AlN by ∼30% and reduce the apparent activation energy of AlN hydrolysis by ∼40 kJ⋅mol−1in SAD. After grinding-leaching treatment, up to 94.3% AlN, and most of Al4C3, Al2S3and AlP were hydrolyzed and transformed into honeycomb boehmite (AlOOH). The leachability of F-, Cl-, NH4+, and heavy metals of the treated SAD was evaluated and met the specified requirements for pollution control. Moreover, adsorbent with uniformly covered active γ-alumina was prepared by roasting the harmless product at 600℃ for 2 h. The BET surface area and total pore volume of the as-prepared adsorbent reached 424 m2/g and 1.30 cm3/g, respectively, and the adsorption capacity of the adsorbent for F-reached 6.40 mg/g. Overall, the novel approach had the advantages of no additives, short process, and simple operation, which was expected to provide deep insights into the harmless treatment and reutilization of SAD.

•Comprehensive sustainability of the photovoltaic module is assessed from a life cycle perspective.•Processes of panel assembly and ingot casting show the highest overall risks.•Environmental risks mainly fall in climate change indicator and social risks in illiteracy indicator.•The highest added value in life cycle costing is panel assembly process.

A systematic study on chemical constituents of the roots of Astragalus ernestiiwas performed by silica gel, sephadex LH-20, MCI gel and Rp-18 column chromatography and spectral analysis such as MS, 1D and 2D NMR. As a result, nine cycloartane triterpenoid saponins were obtained from the methanol extract including a new compound asernestioside D (1), along with eight known constituents, 3-O-β-d-xylopyranosyl-3β,6a,16β,20(S),24(R),25-hexahydroxycycloartane (2), cycloasgenin C-3-O-β-d-xylopyranoside (3), cycloascidoside (4), cyclosiversigenin-3-O-β-d-xylopyranoside (5), isoastragaloside IV (6), asernestioside A (7), asernestioside B (8), and asernestioside C (9).

A resorufin-based isoform-specific fluorescent probe (CHPO) has been designed and developed for highly selective and sensitive sensing cytochrome P450 1A1 (CYP1A1) activities in complex biological systems. CHPO has been successfully used for high-throughput screening of CYP1A1 inhibitors and sensing CYP1A1 activities in living systems, which strongly facilitate the investigations on the biological functions of CYP1A1 in complex biological systems.

Shenhu Area is located in the Baiyun Sag of Pearl River Mouth Basin, which is on the northern continental slope of the South China Sea. Gas hydrates in this area have been intensively investigated, achieving a wide coverage of the three-dimensional seismic survey, a large number of boreholes, and detailed data of the seismic survey, logging, and core analysis. In the beginning of 2020, China has successfully conducted the second offshore production test of gas hydrates in this area. In this paper, studies were made on the structure of the hydrate system for the production test, based on detailed logging data and core analysis of this area. As to the results of nuclear magnetic resonance (NMR) logging and sonic logging of Well GMGS6-SH02 drilled during the GMGS6 Expedition, the hydrate system on which the production well located can be divided into three layers: (1) 207.8–253.4 mbsf, 45.6 m thick, gas hydrate layer, with gas hydrate saturation of 0–54.5% (31% av.); (2) 253.4–278 mbsf, 24.6 m thick, mixing layer consisting of gas hydrates, free gas, and water, with gas hydrate saturation of 0–22% (10% av.) and free gas saturation of 0–32% (13% av.); (3) 278–297 mbsf, 19 m thick, with free gas saturation of less than 7%. Moreover, the pore water freshening identified in the sediment cores, taken from the depth below the theoretically calculated base of methane hydrate stability zone, indicates the occurrence of gas hydrate. All these data reveal that gas hydrates, free gas, and water coexist in the mixing layer from different aspects.

Clayey silt reservoirs bearing natural gas hydrates (NGH) are considered to be the hydrate-bearing reservoirs that boast the highest reserves but tend to be the most difficult to exploit. They are proved to be exploitable by the first NGH production test conducted in the South China Sea in 2017. Based on the understanding of the first production test, the China Geological Survey determined the optimal target NGH reservoirs for production test and conducted a detailed assessment, numerical and experimental simulation, and onshore testing of the reservoirs. After that, it conducted the second offshore NGH production test in 1225 m deep Shenhu Area, South China Sea (also referred to as the second production test) from October 2019 to April 2020. During the second production test, a series of technical challenges of drilling horizontal wells in shallow soft strata in deep sea were met, including wellhead stability, directional drilling of a horizontal well, reservoir stimulation and sand control, and accurate depressurization. As a result, 30 days of continuous gas production was achieved, with a cumulative gas production of 86.14 ×104m3. Thus, the average daily gas production is 2.87 ×104m3, which is 5.57 times as much as that obtained in the first production test. Therefore, both the cumulative gas production and the daily gas production were highly improved compared to the first production test. As indicated by the monitoring results of the second production test, there was no anomaly in methane content in the seafloor, seawater, and atmosphere throughout the whole production test. This successful production test further indicates that safe and effective NGH exploitation is feasible in clayey silt NGH reservoirs. The industrialization of hydrates consists of five stages in general, namely theoretical research and simulation experiments, exploratory production test, experimental production test, productive production test, and commercial production. The second production test serves as an important step from the exploratory production test to experimental production test.

This paper presents a closed-form solution for the temperature prediction in selective laser melting (SLM). This solution is developed for the three-dimensional temperature prediction with consideration of heat input from a moving laser heat source, and heat loss from convection and radiation on the part top boundary. The consideration of heat transfer boundary condition and latent heat in the closed-form solution leads to an improvement on the understanding of thermal development and prediction accuracy in SLM, and thus the usefulness of the analytical model in the temperature prediction in real applications. A moving point heat source solution is used to calculate the temperature rise due to the heat input. A heat sink solution is used to calculate the temperature drop due to heat loss from convection and radiation on the part boundary. The heat sink solution is modified from a heat source solution with equivalent power due to heat loss from convection and radiation, and zero-moving velocity. The temperature solution is then constructed from the superposition of the linear heat source solution and linear heat sink solution. Latent heat is considered using a heat integration method. Ti-6Al-4V is chosen to test the presented model with the assumption of isotropic and homogeneous material. The predicted molten pool dimensions are compared to the documented values from the finite element method and experiments in the literature. The presented model has improved prediction accuracy and significantly higher computational efficiency compared to the finite element model.

Bottom simulating reflector (BSR) has been recognized as one of the indicators of gas hydrates. However, BSR and hydrate are not one-to-one correspondence. In the Xisha area of South China Sea (SCS), carbonate rocks wildly develop, which continuously distribute parallel to the seafloor with high amplitude on seismic sections, exhibiting reflections similar to BSRs in the Shenhu area nearby. This phenomenon causes some interference to hydrates identification. In this paper, the authors discussed the typical geophysical differences between carbonate rocks and hydrates, indicating that the main difference exists in relationship between porosity and velocity, causing different amplitude versus offset (AVO) characters. Then the authors proposed a new model assuming that the carbonates form the matrix and the hydrate fill the pore as a part of the matrix. The key modeling parameters have been optimized constrained by P-velocities and S-velocities simultaneously, and the model works well both for carbonate rock and gas hydrate bearing sediments. For quantitative identification, the authors calculated the velocities when carbonates and hydrates form the matrix together in different proportions. Then they proposed a carbonate and hydrate identification template (CHIT), in which the possible hydrate saturation (PHS) and possible carbonate content (PCC) can be both scaled out for a group of sample composed by P-velocity and S-velocity. If PHS is far larger than PCC, it is more likely to be a hydrate sample because carbonates and hydrates do not coexist normally. The real data application shows that the template can effectively distinguish between hydrates and carbonate rocks, consequently reducing the risk of hydrate exploration.

Dipeptidyl peptidase-IV (DPP-IV), an important prolyl-specific peptidase in the serine hydrolase family, hydrolyzes a large number of endogenous oligopeptides. In clinical studies, the detection of DPP-IV, especially the detection of its activity, is particularly important. We previously reported a specific fluorescent two-photon probe for DPP-IV. In this study, to further verify that our probe can be used for DPP-IV activity detection, we developed an accurate and sensitive method for the determination of DPP-IV activity in human tissue microsomes, cell homogenates or cell supernatants by liquid chromatography-fluorescence detection (LC-FD). This method is based on the fluorescence generated from BAN obtained from the hydrolysis of GP-BAN by detecting DPP-IV. The linearity, sensitivity, recovery, precision and stability of the method were fully validated. The method based on LC-FD has a lower limit of quantitation for BAN (product of DPP-IV), as low as 5 nM (only needs 2 μL), which is much lower than that of the others. This method also demonstrated good accuracy and precision; variances of both were less than 15% between the intra- and inter-assay. In addition, the method was successfully applied to the determination of DPP-IV activity in various cell homogenates and cell supernatants. The development of the LC-FD method will help to understand the expression and function of DPP-IV in different biological samples in humans for future studies.

The ghrelin receptor, also known as the growth hormone secretagogue receptor 1a (GHS-R1a), is a G-protein coupled receptor that is differentially expressed in healthy tissue and several cancers, including prostate, testicular, and ovarian. Selectively targeting the ghrelin receptor using fluorine-18 tagged entities would allow localization and visualization of ghrelin receptor expressing carcinomas using PET imaging. The endogenous ligand ghrelin, a 28 amino acid peptide with 3.1 nM affinity, has poor in vivo stability. Here we report on ghrelin(1-8) analogues bearing modifications at residues 1, 3, 4, and 8. The lead analogue, [Inp1,Dpr3(6-fluoro-2-naphthoate),1-Nal4,Thr8]ghrelin(1-8), possessed an IC50value of 0.11 nM that is a 28-fold improvement compared to the natural ligand. A novel 6-fluoro-2-pentafluorophenyl naphthoate (PFPN) prosthetic group was synthesized to incorporate fluorine-18 for PET imaging. This is not only the highest affinity ghrelin analogue reported, it is also the shortest ghrelin analogue capable of binding GHS-R1a with better affinity than ghrelin(1-28).

Post-operative adhesions, a common complication of surgery, cause pain, impair organ functionality, and often require additional surgical interventions. Control of inflammation, protection of injured tissue, and rapid tissue repair are critical for adhesion prevention. Adhesion barriers are biomaterials used to prevent adhesions by physical separation of opposing injured tissues. Current adhesion barriers have poor anti-inflammatory and tissue regenerative properties. Umbilical cord tissue (UT), a part of the placenta, is inherently soft, conforming, biocompatible, and biodegradable, with antimicrobial, anti-inflammatory, and antifibrotic properties, making it an attractive alternative to currently available adhesion barriers. While use of fresh tissue is preferable, availability and short storage time limit its clinical use. A viable cryopreserved UT (vCUT) “point of care” allograft has recently become available. vCUT retains the extracellular matrix, growth factors, and native viable cells with the added advantage of a long shelf life at −80 °C. In this study, vCUT's anti-adhesion property was evaluated in a rabbit abdominal adhesion model. The cecum was abraded on two opposing sides, and vCUT was sutured to the abdominal wall on the treatment side; whereas the contralateral side of the abdomen served as an internal untreated control. Gross and histological evaluation was performed at 7, 28, and 67 days post-surgery. No adhesions were detectable on the vCUT treated side at all time points. Histological scores for adhesion, inflammation, and fibrosis were lower on the vCUT treated side as compared to the control side. In conclusion, the data supports the use of vCUT as an adhesion barrier in surgical procedures.

The solubilities of 1,3,5-trifluoro-2,4,6-triiodobenzene (IFB) in 12 pure organic solvents including methanol, ethanol, acetone, toluene, ethyl acetate, 1,4-dioxane, 1,2-dichloroethane, acetonitrile, tetrahydrofuran, 1-propanol, 2-propanol, and n-hexane were determined from 289.25 to 332.15 K at atmospheric pressure using the synthetic method. It was found that the solubilities of IFB in different solvents increase with increasing temperature. The experimental solubilities of IFB were regressed by the modified Apelblat equation, λhequation, and Wilson model. The modified Apelblat equation fits the best with the experimental solubilities of IFB with the average relative deviations less than 1.44%.

The solubilities of 2-oxindole in 12 pure organic solvents including acetonitrile (MeCN), dichloromethane, 1,4-dioxane, ethyl acetate (EtOAc), acetone, toluene, methanol, ethanol, 2-propanol, tetrahydrofuran, 1-butanol, and 1-propanol were experimentally measured from (283.15 to 358.15) K at normal pressure p= 0.1 MPa by employing the synthetic method. The measured solubilities of 2-oxindole in these pure organic solvents were found to increase with the rise of temperature. The experimental solubilities of 2-oxindole were correlated with several thermodynamic models including the modified Apelblat equation, λh(Buchowski) equation, Wilson equation, and nonrandom two-liquid equation. These data could be applied for the large-scale synthesis of 2-oxindole with high purity.

Objective:Wound healing is a complex process involving the dynamic interplay of various types of cells and bioactive factors. Impaired wound healing is characterized by a loss in synchronization of the process, resulting in non-healing chronic wounds. Human amniotic membrane (AM) has been shown to be effective in the management of chronic wounds. Recently, a viable lyopreserved AM (VLAM) has been developed. The VLAM retains the structural, molecular, and functional properties of fresh AM with the advantage of a long shelf life for living tissue at ambient temperatures. The objective of this study was to evaluate the effects of VLAM on the impaired wound microenvironment and wound closure in db/db mice.Approach:VLAM or saline gel (control) was applied weekly to 7-mm excisional wounds in diabetic (db/db) mice. Wound appearance and size were assessed weekly. Inflammation and redox state in wounds were tested by cytokine gene and protein expression, and by catalase and glutathione peroxidase activities, respectively. Wound tissue granulation and neovascularization were assessed histologically.Results:Diabetic wounds treated with VLAM closed faster than control wounds. On an average, VLAM-treated wounds closed 4 days faster than the control wounds, with a significantly faster rate of closure at days 7 and 14 as compared with control wounds. The faster closure correlated with a decrease in the expression of proinflammatory factors and oxidative stress, and an increase in angiogenesis and dermal thickness.Innovation:Effects of VLAM on a chronic wound microenvironment and underlying molecular mechanisms were investigated for the first time.Conclusion:VLAM accelerates wound closure in db/db mice by decreasing inflammation and oxidative stress and supporting wound tissue granulation, neovascularization, and re-epithelialization.

Continuous-wave (CW) mid-infrared (MIR) wavelength conversion is experimentally demonstrated using degenerate four-wave mixing (FWM) between two thulium-doped fiber (TDF) lasers in a silicon waveguide. One TDF laser is homemade with a high power and tunable wavelength, while the other one is a commercial product. The conversion efficiency is measured with respect to the pump power and the signal wavelength detuning. In the 2 μm MIR band, the measured 3 dB conversion bandwidth is 52 nm. It verifies the feasibility of FWM-based wavelength conversion based on silicon waveguides in future MIR optical communication systems.

Although the Shenhu sea area has been a topic and focus of intense research for the exploration and study of marine gas hydrate in China, the mechanism of gas hydrate accumulation in this region remains controversial. The formation rate and evolution time of gas hydrate are the critical basis for studying the gas hydrate formation of the Shenhu sea area. In this paper, based on the positive anomaly characteristics of chloride concentration that measured in the GMGS3-W19 drilling site is higher than the seawater value, we numerically simulated the gas hydrate formation time of GMGS3-W19 site. The simulation results show that the gas hydrate formation rate positively correlates with the chloride concentration when the hydrate reaches the measured saturation. The formation time of gas hydrate in the GMGS3-W19 site is approximately 30 ka. Moreover, the measured chloride concentration is consistent with the in-situ chloride concentration, indicating that the formation rate of gas hydrate at the GMGS3-W19 site is very fast with a relatively short evolution time.

A practical and isoform-specific fluorescent probe based on BIDIPY dye have been designed, synthesized and well characterized for sensing CES1 activities in various biological systems such as living cells, tissues and zebrafish.

Efficient organic gain media with high optical gain and good photostability are highly desirable for organic semiconductor lasers. To shed light on the rational molecular design, in this work, a novel deep-blue organic emitter consisting of a carbazole core substituted by a diphenylamine-functionalized triazine unit and two arms of bifluorene with flexible alkyl chains (denoted as C2) was designed and synthesized. Various basic photophysics and amplified spontaneous emission (ASE) characterizations were conducted with a particular focus to unravel the impact of the molecular structure on the photostability. Relatively low ASE threshold of 7.0 μJ/cm2, high net gain coefficient of 79.9 cm–1(under 40-fold threshold pump fluence), and low optical loss coefficient of 7.0 cm–1were recorded for C2 in neat films. For comparison, C2 was also dispersed into polystyrene (PS), a low-loss transparent matrix, with various ratios to form PS-C2 blend films. Among them, a 50 wt % PS-C2 blend film exhibited a high gain coefficient of 61.8 cm–1and a low-loss coefficient of 5.4 cm–1, manifesting enhanced gain properties in comparison with that of pure C2 sample (52.2 and 7.0 cm–1) under identical pump conditions (10-fold threshold pump fluence). With simple high-ratio blending, the photostability and the film morphology stability under annealing conditions were found to be significantly enhanced, giving rise to highly stable optical gain properties. The optical gain properties of the PS-C2 blend films remained almost unchanged even upon harsh annealing treatment in ambient atmosphere. The results suggest an efficient strategy to enhance the photostability of organic gain media without sacrificing the optical gain properties by combining the merits of robust gain media and a low-loss transparent matrix for achieving efficient and stable organic semiconductor lasers.

Mid-infrared (MIR) integrated waveguides with strong local field enhancement and relatively low loss have shown their potential in nonlinear optical applications. We present a novel highly nonlinear silicon hybrid waveguide by setting an insulator-metal-insulator structure with [2-[4-(dimethylamino)phenyl]-3-([4-(dimethylamino)phenyl]ethynyl)buta-1,3-diene-1,1,4,4-tetracarbonitrile] (DDMEBT) and silver materials into the silicon slot. The mode field is strongly confined in the DDMEBT layers via the surface plasmon polariton effect. Two rectangular silicon nanobridges are used to further confine the optical field and reduce the loss simultaneously. The waveguide dimensions are optimized to obtain a figure of merit as high as 0.55 at 2.1 μm and a zero-dispersion wavelength of 2.06 μm. In a 6.6-mm-long waveguide, a maximum four-wave mixing efficiency of −6.65  dB and a bandwidth of 512 nm (1.894–2.406 μm) can be simultaneously obtained, pumped by a 2.104-μm source with a power of only 500 mW. Our designed waveguide exhibits excellent overall performance for nonlinear optical applications such as all-optical signal processing in the MIR band.

An all-optical wavelength conversion method for telecommunication-band mode-division multiplexing (MDM) signals is proposed in integrated silicon waveguides by using the four-wave mixing effect with a dual-mode pump. By engineering the dispersion profile of the integrated silicon waveguide, the phase-matching conditions are realized simultaneously for the TE_01 mode and the TE_11 mode of the MDM signal in the telecommunication band, and they can be converted to the idler modes simultaneously. In a 1.2-cm-long waveguide, the 3-dB conversion bandwidth reaches 58 nm with a conversion efficiency of −22.3  dB pumped by a 100-mW TE_01 and 105-mW TE_11 pump source.

The parasitic nematode Angiostrongylus cantonensisis the primary pathogen causing eosinophilic meningitis and meningoencephalitis in nonpermissive hosts. The larval parasites are eliminated by the host's immune responses in the central nervous system (CNS) through infiltration of eosinophils and lymphocytes. This study aimed to determine primary alterations of microRNA (miRNA) during A. cantonensisinfection in mice.

The oil expulsion efficiency of hydrocarbon source rocks is a key parameter for predicting conventional oil and gas resources and is closely related to the source rock thickness. Pyrolysis experiments and oil expulsion models were used to establish an oil expulsion efficiency calculation formula and to then analyze the trend of the oil expulsion efficiency. We determine the theoretical maximum oil expulsion efficiency via pyrolysis experiments to investigate hydrocarbon generation and expulsion. Then, we establish three ideal and effective oil expulsion models based on the single-layer source rock thickness: full type, full and transition type, and full and transition and retention type. Finally, we derive a corresponding correction formula for the oil expulsion efficiency. Using a type II1hydrocarbon source rock from the Dongying Sag as an example, we calculate the oil expulsion efficiencies. The oil expulsion efficiencies of single-layer source rocks of different thicknesses exhibit only small differences at a low-maturity stage but exhibit obvious differences at a high-maturity stage. The oil expulsion of thin hydrocarbon source rocks is high, even exceeding 70%, but the oil expulsion of super-thick hydrocarbon source rocks is only approximately 30%. Therefore, the thickness of a single-layer hydrocarbon source rock exerts an important influence on oil expulsion, particularly during the raw oil generation and peak discharge stages.

Listeria monocytogenes, one of the most important foodborne pathogens, can cause listeriosis, a lethal disease for humans. L. ivanovii, which is closely related to L. monocytogenes,is also widely distributed in nature and infects mainly warm-blooded ruminants, causing economic loss. Thus, there are high priority needs for methodologies for rapid, specific, cost-effective and accurate detection, characterization and subtyping of L. monocytogenesand L. ivanoviiin foods and environmental sources. In this review, we (A) described L. monocytogenesand L. ivanovii, world-wide incidence of listeriosis, and prevalence of various L. monocytogenesstrains in food and environmental sources; (B) comprehensively reviewed different types of traditional and newly developed methodologies, including culture-based, antigen/antibody-based, LOOP-mediated isothermal amplification, matrix-assisted laser desorption ionization-time of flight-mass spectrometry, DNA microarray, and genomic sequencing for detection and characterization of L. monocytogenesin foods and environmental sources; (C) comprehensively summarized different subtyping methodologies, including pulsed-field gel electrophoresis, multi-locus sequence typing, ribotyping, and phage-typing, and whole genomic sequencing etc. for subtyping of L. monocytogenesstrains from food and environmental sources; and (D) described the applications of these methodologies in detection and subtyping of L. monocytogenesin foods and food processing facilities.

Prion protein has drawn great attention due to its pathological potential to prion diseases. Discriminate and detection of the trace quantities PrPSc is an important measure for prion disease diagnosis at the presymptomatic stage. In this study, we developed a novel sandwich surface plasmon resonance (SPR) assay for the detection of PrPSc, involving bare gold surfaces and bare gold nanoparticles. PrPSc can be captured by the SPR sensing surface via a surface assisted coupling reaction between its intra-molecular disulfide bond and the gold atoms, while PrPC cannot bind to the gold surface strongly. The gold nanoparticles were proved to amplify the SPR detection signals via the coupling of their localized surface plasmon (LSP) with the propagating plasmon on the SPR gold surface. Our results confirmed that the bare SPR gold surface successfully captured the PrPSc from the solution with a LOD of 0.5ng/mL and a linear detection range from 0.5ng/mL to 500ng/mL. Injecting the gold nanoparticles after PrPSc yielded a dramatic enhancement of signal, with a lower LOD of 0.001ng/mL and a linear detection range from 0.001ng/mL to 10ng/mL. The gold nanoparticles permitted 4 to 322-fold increase of the signals. The required detection time was controlled in 15 min. PrPC, cys-protein G and their mixtures with PrPSc, were also detected via this sandwich SPR detection assay. Atomic force microscope (AFM) was used to evaluate the surface morphology of the SPR gold substrate after the detection. All the obtained results suggested that this novel SPR sandwich detection assay in our work was efficient, sensitive and specific for the detection of trace PrPSc

Nonlinear enhancement is experimentally demonstrated by depositing graphene scraps from graphene ethanol dispersion onto a tapered microfiber. The enhancement of the nonlinearity is verified by observing the four-wave mixing (FWM) effect in the homemade graphene-deposited microfiber (GDMF). When the incident pump power is 24.2 dBm, the FWM conversion efficiency in the GDMF reaches −57.1  dB. Compared to the bare microfiber with the same dimensions, the conversion efficiency is improved by more than 3 dB. Our fabricated GDMF provides a simple way to enhance the fiber nonlinearity, and it will be suitable for nonlinear applications such as wavelength conversion and other optical signal processing operations.

Listeria monocytogenesis an important foodborne pathogen responsible for listeriosis, a fatal disease. It is widely distributed in various foods and environmental sources. In this review, we focused on addressing PCR-based technologies, including conventional PCR, qPCR and droplet digital PCR (ddPCR). Specifically, we described (a) conventional PCR and mono-, duplex- and multiplex-qPCR methodologies; (b) development and applications of gene HlyA-, Iap-, PrfA– and SsrA-based conventional and qPCR assays as well as PCR assays targeting newly identified gene targets for specific detection of L. monocytogenes; differentiation of viable from dead L. monocytogenesby qPCR in conjugation with propidium monoazide pretreatment; PCR-based serotype identification of L. monocytogenesisolates; PCR-based detection of L. ivanovii,infecting ruminants, differentiation of L. monocytogenesfrom other Listeriaspecies; and sigB-gene based PCR identification of Listeria spp; (c) applications of ddPCR in detection of L. monocytogenes; and (d) application of qPCR assays in detection and subtyping of L. monocytogenesin milk and dairy products; meats, meat products and meat-processing environment; and seafood, seafood products and processing environment. Our goal was to provide a relatively comprehensive overview of PCR-based methodologies available in detection, characterization and subtyping of various strains of L. monocytogenesin foods and environmental sources.

Studies were conducted to disclose the feasibility of membrane in simulated electroplating rinse wastewater. Single nanofiltration (NF) and reverse osmosis (RO) membrane were carried out under different operation pressure, temperature and feed Ni2+concentration. These four hybrid systems, built in concentrate staging, were investigated under optimized conditions. The results demonstrated that permeate flux of NF membrane, which was substandard (>0.5 mg/L), was almost double that of RO membrane. The values obtained for water recovery were 39.00%, 0%, 20.00% and 18.33%, concentration ratio were 1.60, 4.90, 2.45 and 2.45. The total exergy loss of four systems was 0.241, 0.460, 0.350 and 0.362MJ/h for RO–RO, NF–NF, RO–NF and NF–RO system, respectively. The specific entropy production (SEP) and unit production water cost were 0.69, 2.01 and 2.19 MJ/m3and 0.38, 0.46 and 0.50 $/m3for RO–RO, RO–NF and NF–RO system, respectively. So RO–RO system had the highest freshwater flow rate, lowest exergy loss and SEP, but NF–NF system had the highest concentration ratio and the highest exergy loss. In total, RO–NF and NF–RO system integrated the performance of the first two; furthermore RO–NF system was superior to NF–RO system as a whole.

The combined strengthening effect of grain refinement by equal channel angular pressing (ECAP) and aging on a wrought Mg-12Gd-3Y-0.5Zr (mass fraction, %) alloy was investigated. The resulting mechanical properties and microstructures were examined by uniaxial tensile test, optical microscope (OM) and transmission electronic microscope (TEM). It is found that ECAP for 4 passes at 673K followed by aging treatment at 523K for 16h is the optimum condition to strengthen the selected alloy Microstructure analysis reveals that precipitates appear at grain boundaries, accompanies by a few precipitates in grain interior after ECAP and aging treatment. By contrast of as-annealed sample, the strength and elongation were improved which revealed that grain boundaries and precipitation hardening were the main contributor to the high tensile strength of the experimental alloy.