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Microbial-induced carbonate precipitation (MICP) is a relatively innovative and environmentally-friendly soil reinforcement technology, primarily used on sand, but its application in loess has rarely been studied. This paper explores the viability of the MICP technique for improving the engineering properties of typical loess. Sporosarcina pasteurii was used to trigger carbonate precipitation. Factors such as reaction temperature, pH of the media, and the inoculation ratio were adopted to determine the optimum conditions. Different concentrations of Sporosarcina pasteurii and cementation reagent were selected for combination to treat the loess samples with a self-designed vacuum test device. The unconfined compressive strength and calcium carbonate content of the treated samples were tested and Scanning Electron Microscopy (SEM) was carried out to evaluate the improving effect. The results showed that the optimum conditions are reaction temperature of 30°C, pH of the media of 9, a higher inoculation ratio can produce higher enzyme activity and monomer enzyme activity. The engineering properties of the MICP-treated loess are significantly improved. The obtained unconfined compressive strength increases nearly 4 times when the OD600 is 1.5 and cementation reagent concentration is 1 mol/L. The test results of calcium carbonate content are consistent with unconfined compressive strength. Finally, the microstructure of loess samples was quantitatively analyzed by Pore (Particle) and cracks analysis system (PCAS). It was showed that MICP has a great influence on the surface porosity, followed by the pore fractal dimension and the probability entropy, but has little influence on the pore average form factor.

The functionalization of waxy corn starch (WCS) was better realized by combing the cross-linking of epichlorohydrin with oxidation of sodium periodate. The results indicated that the cross-linking had a greater influence on the retrogradation than the oxidation, and the oxidation worsened the freeze–thaw stability of WCS. Both cross-linking and oxidation could ameliorate the alkali and acid resistance of WCS, and enhanced its heat stability. Cross-linking weakened the absorption peak of the –OH groups according to FTIR and had a small influence on the crystalline configuration of WCS belonging to a typical A-type structure, whereas the oxidation almost entirely damaged the particle structure. After the cross-linking, the tiny pits with a diameter of around 1 μm only appeared on sides of WCS granules, and proving that the cross-linking was very unevenly completed on some of WCS particles. The pasting curve of WCS was obviously different from those of its derivatives. The combination of oxidation and cross-linking could effectively decrease the setback of WCS.

The interlayer bonding in two-dimensional (2D) materials is particularly important because it is not only related to their physical and chemical stability but also affects their mechanical, thermal, electronic, optical, and other properties. To address this issue, we report the direct characterization of the interlayer bonding in 2D SnSe using contact-resonance atomic force microscopy (CR-AFM) in this study. Site-specific CR spectroscopy and CR force spectroscopy measurements are performed on both SnSe and its supporting SiO2/Si substrate comparatively. Based on the cantilever and contact mechanic models, the contact stiffness and vertical Young’s modulus are evaluated in comparison with SiO2/Si as a reference material. The interlayer bonding of SnSe is further analyzed in combination with the semi-analytical model and density functional theory calculations. The direct characterization of interlayer interactions using this non-destructive methodology of CR-AFM would facilitate a better understanding of the physical and chemical properties of 2D layered materials, specifically for interlayer intercalation and vertical heterostructures.

To promote sustainability, it has become increasingly vital to properly account material and energy flows in industrial production processes. Therefore, a generic process-level input–output (IO) model was developed to provide an integrated energy (material) accounting and analysis approach for industrial production processes. By extending the existing process-level IO models, the production, usage, export and loss of by-products were explicitly considered in the proposed IO model. Moreover, the by-products allocation procedures were incorporated into the proposed IO model to reflect individual contributions of products to energy consumption. Finally, the proposed model enabled calculating embodied energy of main products and total energy consumption under hierarchical accounting scope. Plant managers, energy management consultants, governmental officials and academic researchers could use this input–output model to account material and energy flows, thus calculating energy consumption indicators of a production process with their specific system boundary requirements. The accounting results could be further used for energy labeling, identifying bottlenecks of production activities, evaluating industrial symbiosis effects, improving materials and energy utilization efficiency, etc. The model could also be used as a planning tool to determine the effect that a particular change of technology and supply chains may have on the industrial production processes. The proposed model was tested and applied in a real integrated steel mill, which also provided the reference results for related researches. At last, some concepts, computational issues and limitations of the proposed model were discussed.

A hierarchical structural decomposition analysis (SDA) model has been developed based on process-level input-output (I-O) tables to analyze the drivers of energy consumption changes in an integrated steel plant during 2011-2013. By combining the principle of hierarchical decomposition into D&L method, a hierarchical decomposition model for multilevel SDA is obtained. The developed hierarchical IO-SDA model would provide consistent results and need less computation effort compared with the traditional SDA model. The decomposition results of the steel plant suggest that the technology improvement and reduced steel final demand are two major reasons for declined total energy consumption. The technical improvements of blast furnaces, basic oxygen furnaces, the power plant and the by-products utilization level have contributed mostly in reducing energy consumption. A major retrofit of ancillary process units and solving fuel substitution problem in the sinter plant and blast furnace are important for further energy saving. Besides the empirical results, this work also discussed that why and how hierarchical SDA can be applied in a process-level decomposition analysis of aggregated indicators.

Plasmodium falciparum is responsible for the vast majority of the morbidity and mortality associated with malaria infection globally. Although a number of studies have reported the emergence of drug resistance in different therapies for P. falciparum infection, the degree of the drug resistance in different antimalarials is still unclear. This research investigated the risk of drug resistance in the therapies with different medications based on meta-analyses. Relevant original randomized control trials (RCTs) were searched in all available electronic databases. Pooled relative risks (RRs) with 95% confidence intervals (95% CIs) were used to evaluate the risk of drug resistance resulting from different treatments. Seventy-eight studies were included in the meta-analysis to compare drug resistance in the treatment of P. falciparum infections and yielded the following results: chloroquine (CQ)sulfadoxine-pyrimethamine (SP) (RR = 3.67, p 0.001 ), mefloquine (MQ)SP (RR = 0.26, p 0.001), artesunate + sulfadoxine-pyrimethamine (AS + SP)artemether + lumefantrine (AL) (RR = 2.94, p 0.001), dihydroartemisinin + piperaquine (DHA + PQ)AL (RR = 0.7, p 0.05), and non-artemisinin-based combination therapies (NACTs)artemisinin-based combination therapies (ACTs) (RR = 1.93, p 0.001); no significant difference was found in amodiaquine (AQ) vs. SP, AS + AQ vs. AS + SP, AS + AQ vs. AL, or AS + MQ vs. AL. These results presented a global view for the current status of antimalarial drug resistance and provided a guidance for choice of antimalarials for efficient treatment and prolonging the life span of the current effective antimalarial drugs.

Recently, long-range surface plasmon resonance (LRSPR) sensor has attracted a great deal of attention as a potentially non-destructive and label-free technique for cellular studies in real time. Thus, much effort has been placed on the fabrication and optimization of multilayered structure required for the excitation of LRSPR. In this work, a detailed study about the influence of both plasma polymerized dielectric buffer layer (DBL) and thin gold film on the excitation of LRSPR was performed. The DBLs of different thicknesses were deposited directly onto SF11 glass slides by radio frequency plasma polymerization (pp) of perfluorooctyl ethylene (PFOE). Thereafter, Au films of different thicknesses were thermally evaporated onto the ppPFOE layers. Atomic force microscopy (AFM) results suggest that the resulting SF11/ppPFOE/Au structure has a smooth surface regardless of Au film’s thickness. LRSPR measurements indicate that the excitation of LRSPR relies not only on the thickness of the ppPFOE buffer layer, but also on the thickness and optical property of thin Au film. Theoretical simulation based on Fresnel’s equation allows for the determination of both the thickness and optical constant of each layer supporting the LRSPR, and also enables us to predict the optimum combination of ppPFOE and Au film in a LRSPR sensor. The performance of various LRSPR sensors to monitor the bulk refractive index variation has also been investigated.

The 885 nm direct pumping directly into the 4F3/2 emitting level of Nd3+ is applied on an Nd:Lu0.15Y0.85VO4 crystal. The maximum output power of 2.8 W for continuous wave (CW) operation is obtained. For Q-switched operation, the maximum average output power is 1.2 W with pulse repetition of 23.69 kHz and pulse width of 35 ns at the pump power of 27.9 W. The high-quality fundamental transverse mode can be observed owing to the reduction of thermal effect for Nd:Lu0.15Y0.85VO4 crystal by 885 nm direct pumping.

In this work, lanthanide doped zinc oxide nanoparticles synthesized in room-temperature ionic liquid via a sonochemical method have been studied. Firstly, the cavitation bubble temperatures in 1-butyl-3-methylimidazolium hexafluorophosphate (ImPF6) have been estimated by the methyl radical recombination method. The temperatures measured in ImPF6 are in the range of 3000–4000 K. Secondly, a facile method has been proposed to prepare lanthanide (III) doped zinc oxide nanoparticles in ImPF6 via an ultrasonic irradiation. The nanomaterials are studied by transmission electron microscopy, X-ray diffraction, photoacoustic and luminescence techniques. The results show that the relaxation processes of the samples depend strongly on the lanthanide doping. Moreover, a mechanism is proposed to interpret the formation of lanthanide (III) doped zinc oxide nanoparticles in the ImPF6 upon ultrasonic irradiation.

In this study, fairly uniform anatase TiO2 spheres doped with neodymium (III) have been prepared. It is found that the impregnation of neodymium (III) can remarkably inhibit the anatase–rutile transition. In order to analyze the correlation of the dopant effect with the local environment of neodymium (III) ions, photoacoustic spectra of the f–f transitions of neodymium (III) have been studied. The variation of the nephelauxetic parameters can be attributed to the substitutional neodymium (III) ions at low doping level (≤ 1 mol%), and to both the substitutional and interstitial neodymium (III) ions at high doping level (1 mol% to 8 mol%). The phase transformation mechanism of the samples has been interpreted based on the X-ray diffraction and transmission electron microscopy results. The nephelauxetic parameters are the same for all the samples calcined at 1150 °C. This is due to the segregation of neodymium (III) ions in the samples as a separated phase.

In this study, lanthanide complexes Tb(o-HBA)3 · H2O and Ln(o-HBA)3· H2O (o-HBA: o-hydroxy benzoic acid; Ln3+:Y3+ or Er3+) co-doped silica samples have been prepared via a sol–gel method. The photoacoustic (PA) intensity of the ligand decreases with the addition of the Y3+ complex, and increases remarkably with the addition of the Er3+ complex. Different PA intensities of the samples are interpreted by comparison with their luminescence spectra. The luminescence quantum yields, which are accurate within 10%, have been determined to be 26 %, 22 %, and 6.9% for the silica samples doped with Tb3+–Y3+ complexes, Tb3+ complex, and Tb3+–Er3+ complexes, respectively. A possible mechanism for the co-luminescence phenomena is proposed.

Recently, photoacoustic (PA) spectroscopy has emerged as a valuable tool for the study of various kinds of materials. Herein, we present the results of PA spectral studies of chemical materials. First, the PA study on luminescent materials in condensed states is reported. Combining with the luminescence technique, the energy transfer efficiency and the intrinsic luminescence quantum yield are determined for a europium (III) complex in the glassy state, smectic A phase, and the isotropic liquid. Second, neodymium (III) compounds with l-glycine, l-phenylalanine, and l-tryptophan are synthesized and their PA spectra are reported. The nephelauxetic ratio and Sinha parameter are calculated based on the PA spectra. The environmental effect on the f–f transitions of the neodymium(III) ion is also studied.

In this paper, we mainly discuss the normality of two families of functions concerning shared values and proved: Let F and G be two families of functions meromorphic on a domain D ⊂ ℂ, a1, a2, a3, a4 be four distinct finite complex numbers. If G is normal, and for every f e F, there exists g e G such that f(z) and g(z) share the values a1, a2, a3, a4, then F is normal on D.

Let F be a family of functions holomorphic on a domain D ⊂ ℂ Let k ≥ 2 be an integer and let h be a holomorphic function on D, all of whose zeros have multiplicity at most k −1, such that h(z) has no common zeros with any f ∈ F. Assume also that the following two conditions hold for every f ∈ F: (a) f(z) = 0 ⇒ f′(z) = h(z); and (b) f′(z) = h(z) ⇒ |f(k)(z)| ≤ c, where c is a constant. Then F is normal on D.

The isothermal and cyclic oxidizing kinetics of Co-40Cr alloy and its lanthanum ion-implanted samples were studied at 1 000 °C in air by thermal gravimetric analysis (TGA). Scanning electron microscopy (SEM) was used to examine the Cr 2 O 3 oxide film's morphology after oxidation. Secondary ion mass spectrum (SIMS) method was used to examine the binding energy change of chromium caused by La-doping and its influence on the formation of Cr 2 O 3 film. Acoustic emission (AE) method was used in situ to monitor the cracking and spalling of oxide films during oxidizing and subsequent air-cooling stages. Laser Raman spectrum was used to examine the stress changes within oxide films. A theoretical model was proposed relating to the film fracture process and was used to analyze the AE spectrum both on time domain and AE-event number domain. It was found that lanthanum implantation remarkably reduced the isothermal oxidizing rate of Co-40Cr and improved the anti-cracking and anti-spalling properties of Cr 2 O 3 oxide film. The reasons for the improvement were mainly that the implanted lanthanum reduced the grain size and internal stress of Cr 2 O 3 oxide, increased the high temperature plasticity of oxide film, and remarkably reduced the number and size of Cr 2 O 3 /Co-40Cr interfacial defects.

Lanthanide complexes Ln(bta)3L2 (Ln3+: Eu3+, Tb3+ and Ho3+; bta: benzoyltrifluoroacetonate; L: N-octadecyl-2-hydroxy-4-tetradecyloxybenzal- dimine) are synthesized. Their photoacoustic (PA) spectra are reported and interpreted. In the region of ligand absorption, PA intensity increases for Eu(bta)3L2, Tb(bta)3L2 and Ho(bta)3L2, respectively. It is found that the PA intensity of the ligand bears a relation to the intramolecular energy transfer process. By comparison with luminescence spectra, the energy transfer process and phase transition of lanthanide complexes are studied from two aspects: radiative and nonradiative processes.

For the detection of wheat yellow mosaic virus (WYMV), we established a reverse transcription loop-mediated isothermal amplification (RT-LAMP) method. Using Primer Explorer software, four sets of primers were designed and RT-LAMP assay reaction conditions were optimized. The RT-LAMP was performed at different times by four primer sets. Agarose gel analysis showed that WYMV could be detected after 30 min with the primer set III and after 45 min with the other three primer sets, both under the 80-min reaction time. RT-LAMP had the same results with the four primer sets, thus primer set III and 65°C for 80 min reaction were selected for virus detection. There was no significant different when avian myeloblastosis virus (AMV) and moloney murine leukemia virus (M-MLV) RT-LAMP with the four primer sets and M-MLV was chosen due to its relatively cheap price. The result on specificity showed that the assay could amplify WYMV specifically, and the sensitivity comparison showed that the RT-LAMP was 100 times more sensitive than conventional reverse-transcriptase-polymerase chain reaction (RT-PCR). Overall, RT-LAMP was found to be a simple, specific, sensitive, convenient and time-saving method for WYMV detection.

Background We apply a new machine learning method, the so-called Support Vector Machine method, to predict the protein structural class. Support Vector Machine method is performed based on the database derived from SCOP, in which protein domains are classified based on known structures and the evolutionary relationships and the principles that govern their 3-D structure.