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Municipal and industrial wastewater can be a potential source of magnesium. Therefore, the development of magnesium recovery technology can both release the burden of wastewater treatment and help ...

A bimetallic Fe-Cu catalyst was applied as a catalyst for heterogeneous Fenton reaction. Fluidized-bed crystallization of bimetallic catalyst supported by a silica seed (FeIII0.66CuI0.33 @SiO2) was conducted at specific hydraulic conditions. The deposited state of copper and iron of FeIII0.66CuI0.33@SiO2 were identified as Cu(I) and Fe(III), which could effectively catalyze H2O2 to form hydroxyls radical for the abatement and mineralization of benzoic acid under blue light irradiation (436 nm). The cupric species as an electron donor enabled the reductive dissolution of the deposited iron to drive a Fenton reaction. The blue light irradiation promoted the regeneration of Fe(III) to Fe(II) through the photoreduction mechanism. Operating parameters included Fe to Cu ratio (0.5–4), dose of H2O2 (0–4 mM), initial pH (3–7) and light intensity (0–10 mW/cm2). The photo Fenton process using FeIII0.66CuI0.33@SiO2 catalyst resulted in 86% of benzoic acid mineralization in 3 h.

Elucidating hydrogen oxidation reaction (HOR) mechanisms in alkaline conditions is vital for understanding and improving the efficiency of anion-exchange-membrane fuel cells. However, uncertainty remains around the alkaline HOR mechanism owing to a lack of direct in situ evidence of intermediates. In this study, in situ electrochemical surface-enhanced Raman spectroscopy (SERS) and DFT were used to study HOR processes on PtNi alloy and Pt surfaces, respectively. Spectroscopic evidence indicates that adsorbed hydroxy species (OHad ) were directly involved in HOR processes in alkaline conditions on the PtNi alloy surface. However, OHad species were not observed on the Pt surface during the HOR. We show that Ni doping promoted hydroxy adsorption on the platinum-alloy catalytic surface, improving the HOR activity. DFT calculations also suggest that the free energy was decreased by hydroxy adsorption. Consequently, tuning OH adsorption by designing bifunctional catalysts is an efficient method for promoting HOR activity.

PtNi alloy catalysts have excellent catalytic activity and are considered some of the most promising electrocatalysts capable of replacing pure Pt for the oxygen reduction reaction (ORR). For PtNi alloys, Ni-doping can improve performance by changing the electronic and structural properties of the catalyst surface and its interaction with reaction intermediates. However, to date there is no direct spectral evidence detecting or identifying the effect of Ni on the ORR in PtNi alloy catalysts. Herein, we introduce a surface-enhanced Raman spectroscopic (SERS) "borrowing" strategy for investigating ORR processes catalyzed by Au@PtNi nanoparticles (NPs). The bond vibration of adsorbed peroxide intermediate species (*OOH) was obtained, and the effect of Ni on the interaction between surface Pt and *OOH was studied by varying the Ni content in the alloy. The frequency of the *OOH spectral band has an obvious red-shift with increasing Ni content. Combined with density functional theory (DFT) calculations, we show that Ni-doping can optimize *OOH surface binding on the Pt surface, achieving more efficient electron transfer, thus improving the ORR rate. Notably, these results evidence the SERS borrowing strategy as an effective technique for in situ observations of catalytic processes.

Organic–inorganic hybrid Pb-based halide perovskites, especially the well-known MAPbI3, have shown great promise for photovoltaic applications due to their fast-growing power-conversion efficiency (PCE) and low manufacturing cost. However, their poor ambient stability and Pb-toxicity are still challenging issues for future commercialization. Here, by combining first-principles calculations with large-scale screening, we propose a Pb-free all-inorganic Dion–Jacobson perovskite CsSbCl4, which has an optimal bandgap (∼1.4 eV) in the first place. Our calculations also show that CsSbCl4 possesses high carrier mobility (∼102–104 cm2 V−1 s−1) and strong interband optical absorption (∼105 cm−1). Consequently, its spectroscopic limited maximum efficiency can reach up to ∼27%, similar to MAPbI3. Moreover, the TiO2/CsSbCl4/spiro-OMeTAD junction has a PCE of 20.07%, which can be further enhanced by optimizing parameters, such as absorber defect density. These favourable characteristics of CsSbCl4 make it a potential alternative to Pb-based halide perovskites in photovoltaic devices.

Alkali metal anodes (AMAs) with high theoretical capacity, high energy density, and low redox potentials have attracted tremendous attention for high-energy-density batteries. However, their practical applications are hindered by severe metal dendrite growth, detrimental side reactions, and infinite volume expansion during plating and stripping processes. In this review, we summarize the recent advances in AMAs that are enabled by two-dimensional (2D) materials, which by their diverse chemical, physical, electrical, and mechanical properties, contribute to resolving the notorious challenges faced by AMAs, including composite anode construction, separator modification, artificial solid electrolyte interphase, and new electrolyte fabrication. Particular focus is devoted to the advanced characterization techniques and theoretical simulations, with the aim of providing a deeper understanding of the interfacial reactions and insight for the future design of AMAs. Finally, the challenges, potential solutions, and future perspectives for utilizing 2D materials in AMAs are highlighted and presented.

In order to explore the variation law of mechanical properties of tailing sand of a metal ore in Hunan Province under the action of moisture absorption and dehumidification circulation, based on the indoor triaxial test results of tailing sand, this paper introduces the statistical damage theory, combined with the physical and mechanical properties of tailing sand, and studies the elastic-plastic mechanical properties of tailing sand on the basis of the Lemaitre strain equivalent theory. Giving full consideration of the change of tailing sand’s pore and volume in the deformation process, an improved statistical damage constitutive model is proposed; it can reflect that the residual strength of tailings after the peak value still has bearing capacity under the action of dry wet circulation. Compared with the results of indoor triaxial consolidation undrained test, this constitutive model is more reliable.

Acid mine drainage (AMD) released from gold and coal mining contains a large quantity of heavy metals, thus being a threat to the surrounding ecosystem. The recovery of metals from AMD can both address the potential contamination and bring more economic profits. In this study, the sequential selective precipitation and fluidized bed homogeneous crystallization (FBHC) were integrated to recover iron(II) and Al(III) from real AMD wastewater. The selective precipitation of Fe was optimized by adjusting pH. The FBHC recovery of Al performed its best at pH 9.25 ± 0.2, molar ratio of [H2O2]/[Al(III)] = 2.0 and up-flow velocity (U) = 30.5 m/h. Iron(II) and Al(III) were recovered in the form of iron hydroxide (Fe(OH)3) and bayerite (α-Al(OH)3) pellets. Removal efficiencies were as high as 99.7% and 99.3% for Fe(II) and Al(III), respectively. A brief cost-benefit estimation was performed and showed that the estimated profit gained from field-scale recovery of Fe(II) and Al(III) would be $1.31/m3-AMD.

Advanced oxidation process is a promising technology for the treatment of azo dye wastewater, owing to its high degradation performance and less secondary contamination. Herein, the mineralization of azo dye Reactive Black 5 (RB5) by the heterogeneous photo-Fenton process was investigated in a three-phase fluidized bed reactor. The waste iron oxide (denoted as BT) obtained from tannery wastewater process with Fenton’s reagent was selected as a heterogeneous catalyst. The introduction of BT to the UV/H2O2 process (UV/H2O2/BT) shows obviously higher mineralization efficiency because ferric complexes of carboxylic acid, the degradation intermediates of RB5, could be readily decomposed by UV irradiation. The decolorization was achieved by homogenous photo-Fenton reaction induced by leached iron, while the mineralization was contributed to heterogeneous oxidation. Under the conditions of 254 nm UV irradiation, 19.00 mM H2O2, 2.0 g L–1 catalyst loading and natural pH0 of 5.0, 90.2% TOC removal of RB5 could be achieved. The catalyst indicated an acceptable stability and reusability after four cycles. The proposed heterogeneous photo-Fenton process with stable performance is environmental-friendly for the mineralization of RB5.

The alkyne is a biologically significant moiety found in many natural products and a versatile functional group widely used in modern chemistry. Recent studies have revealed the biosynthesis of acetylenic bonds in fatty acids and amino acids. However, the molecular basis for the alkynyl moiety in acetylenic prenyl chains occurring in a number of meroterpenoids remains obscure. Here, we identify the biosynthetic gene cluster and characterize the biosynthetic pathway of an acetylenic meroterpenoid biscognienyne B based on heterologous expression, feeding experiments, and in vitro assay. This work shows that the alkyne moiety is constructed by an unprecedented cytochrome P450 enzyme BisI, which shows promiscuous activity towards C5 and C15 prenyl chains. This finding provides an opportunity for discovery of new compounds, featuring acetylenic prenyl chains, through genome mining, and it also expands the enzyme inventory for de novo biosynthesis of alkynes.

In the paper, the microstructure and mechanical properties of ZYK530 Mg alloy with different aging heat treatment processes were analyzed and studied by OM, SEM, EDS and XRD. The results show that after heat treatment at different temperatures and aging times, the hardness of the alloy first decreases, then increases in a wave-like manner, and then decreases in a wave-like manner after reaching its peak value. The optimum aging process of ZYK530 alloy is T5-220°C×5h, and the maximum hardness is 88.34HRE, which tensile strength, yield strength and elongation are 335MPa, 305MPa and 13.5% respectively. Compared with the untreated forged alloy, the mechanical properties are increased by 6.3%, 4.8% and 35%, which its fracture mechanism is mainly ductile-brittle mixed fracture.

Effect of Ta-alloying on microstructure, martensitic transformation, mechanical property and shape memory effect of Ni54Mn25Ga17.5Ta0.5 alloy has been systematically investigated. The results show that the substructure of Ni-Mn-Ga alloy significantly changed, which was converted from the plate martensite to the lath martensite. Compression tests show that a compressive strength of 1380 MPa with a fracture strain up to 21.92% can be achieved in the Ni54Mn25Ga17.5Ta0.5 alloy at room temperature. This is no changed martensite structure with non-modulated T martensite. In addition, the martensitic transition temperature obviously decreases from 350 °C to 208 °Cand hysteresis loop increases about 20 °Cwhen Ta substituted of Ni. The shape memory effect increased with the increase of pre-deformation, nevertheless, the shape recovery ratio appeared firstly increases and then decreases. When the pre-deformation is 10%, 15%, 20%, the shape memory effect of the alloy is 5.1%, 6.8% and 10%, respectively.

Life history theory predicts that animals often produce fewer offspring of larger size and indicate a stronger trade-off between the number and size of offspring to cope with increasing environmental stress. In order to evaluate this prediction, we tested the life history characteristics of Bufo minshanicus at eight different altitudes on the eastern Tibetan Plateau, China. Our results revealed a positive correlation between female SVL and clutch size or egg size, revealing that larger females produce more and larger eggs. However, high-altitude toads seem to favor more offspring and smaller egg sizes when removing the effect of female SVL, which is counter to theoretical predictions. In addition, there was an overall significantly negative relationship between egg size and clutch size, indicative of a trade-off between egg size and fecundity. Therefore, we suggest that higher fecundity, rather than larger egg size, is a more effective reproductive strategy for this species of anuran living at high-altitude environments.

The Xinxing granitic pluton is a large batholith cropping out in southern South China with its long axis parallel to the regional NE–trending faults. We conduct the first comprehensive study of zircon laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) U–Pb chronology and trace element chemistry, rock-forming mineral chemistry and whole-rock element and Sr–Nd isotope geochemistry for this pluton. Our new data indicate that the pluton was emplaced during the interval 234–232 Ma, i.e. early Indosinian rather than late Mesozoic as previously considered. The southern pluton consists of syenogranite and monzogranite, which are composed of K-feldspar, oligoclase, quartz and ferri-biotite. The northern pluton consists of monzogranite and granodiorite, which are composed of andesine, K-feldspar, quartz and magnesio-biotite. The southern granites have high SiO2 contents (72.5–79.2 wt%) and high FeOT/(FeOT + MgO) (T refers to total) ratios with low Mg# [atomic Mg/(Mg + FeT)]. They are enriched in rare earth elements and depleted in Sr and Ba with Zr + Y + Ce + Nb >350 ppm and 10,000 × Ga/Al >2.6. Their initial magma temperatures are unusually high (>886 °C). All those features strongly suggest an affinity with A-type granites. The northern granites have lower SiO2 contents (63.4–72.5 wt%) and lower FeOT/(FeOT + MgO) ratios as well as higher Mg# than the southern granites. They are also enriched in rare earth elements and depleted in Sr and Ba, with high Ga/Al ratios and high Zr + Y + Ce + Nb contents. Geochemical data and major element modeling confirm that the southern A-type granites were generated by the moderate degree (~49%) shallow (ca. 15–20 km depth) dehydration melting of the early Paleozoic granitoids triggered by intraplating of basaltic magmas. Subsequent moderate degree (~57%) fractionation of such crustal melts produced the more felsic granites in the southern pluton, whereas subsequent mixing of such crustal melts with about 8 to 48% intraplated mafic magmas generated the less felsic granites in the northern pluton. Interaction of mafic magmas with A-type crustal melts causes the northern granites to lose some diagnostic geochemical features of A-type granites such as high FeOT/(FeOT + MgO) ratios and to be transitional towards I-type granites. We further suggest their origin to have been related to the transtension of the regional NE–trending strike-slip faults coupled with the early Indosinian continental collisions.

A lithium titanate (Li2TiO3) precursor colloid with high stability was synthesized via a novel inorganic precipitation–peptization method using low cost titanium sulfate as a titanium source, lithium acetate as a lithium source and hydrogen peroxide as a complexing agent. The formation mechanism of the precursor sol was discussed, and the effect of the addition of triethanolamine (TEOA) and sodium dodecylbenzenesulfonate (SDBS) on the colloidal stability was investigated in detail. Samples were characterized with thermogravimetric analysis–differential scanning calorimetry (TG-DSC), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Brunnauer–Emmet–Teller (BET) analysis. The results indicate that the colloid stability is enhanced by increased dosage of TEOA and SDBS within a certain range. The best colloid stability is achieved when the amount of TEOA added is 0.75%, and the sol system can remain stable for up to 15 days, which is 7.5 times that of the precursor sol without added surfactant. The optimal amount of added SDBS is 0.125%, and the effect of SDBS on colloid stability is not as significant as that of TEOA. SDBS favors the formation of the crystal structure of Li2TiO3, while TEOA inhibits the ordered arrangement of Li+ in the main crystal layer. The sample (Li2TiO3) surface with SDBS shows a porous structure, which is conducive to the subsequent pickling treatment.

Searching for energetic photovoltaic absorbers is a favorable solution to the current energy crisis. As a star material for solar cells, MAPbI3 (MA = CH3NH3) has a suitable band gap, strong optical...

In order to precisely design the active sites in two-dimensional (2D) gold-based catalysts, we have developed a convenient and versatile plasma-assisted droplet evaporation-rigid crosslinking metho...

Fibrous Sm3+-doped TiO2 (Sm/TiO2) was prepared using collagen fibers as a template. Samples were calcined at different temperatures to prepare TiO2 as well as Sm/TiO2, and effects of Sm-doping on crystallization, crystal transformation and grain size were investigated in detail. The morphology, crystalline structure, diffuse reflection spectrum and element chemical status of the products were characterized using scanning electron microscopy (SEM), X-ray diffractometer (XRD), ultraviolet visible spectrophotometry (UV–Vis DRS) and X-ray photoelectron spectroscopy (XPS), respectively. The photocatalytic performance was evaluated by the following degradation of methyl orange. The results show that the original fiber structure of collagen template is fully preserved when calcinations are carried out at 500–700°C. Sm-doping has an significant effect on crystallization and grain size of TiO2. After samarium doping, the band gap of sample decreased from 3.06 to 3.02 eV, the product has a significant red shift of optical absorption band edge, and the absorbance is also enhanced in visible region. The orbit component of O 1s for 4% Sm–TiO2 is shifted to a higher binding energy. The biggest enhancement in photocatalytic activity was obtained with a dopant amount of 4% samarium calcined at 600°C, and the degradation rate of methyl orange reaches 98.22% after 40 min using metal halide lamp (350 W) as illuminant, which is much higher than that of undoped one.

A new heat source model consisted of inverted conical heat source and rotary Gauss body heat source is established using the CAE software for the keyhole effect of laser-TIG hybrid welding. The inverted conical heat source is used for analyzing the wide upper part of weld pool due to the rapid heat up by the laser and arc. The rotary Gauss body heat source model is used for analyzing the long and narrow lower part of weld pool formed by the laser. The result showed that, compared with other single source mode, this new heat source model may get a better simulation of the weld pool morphology, especially the inflection point near the keyhole. It provides a new method to predict the morphology and size of the weld pool of magnesium alloy laser-TIG welding.

In this paper we propose some efficient schemes for the Navier-Stokes equa-tions. The proposed schemes are constructed based on an auxiliary variable reformu-lation of the underlying equations, recently introduced by Li et al. [20]. Our objectiveis to construct and analyze improved schemes, which overcome some of the shortcom-ings of the existing schemes. In particular, our new schemes have the capability to capture steady solutions for large Reynolds numbers and time step sizes, while keeping the error analysis available. The novelty of our method is twofold: i) Use the Uzawa algorithm to decouple the pressure and the velocity. This is to replace the pressure-correction method considered in [20]. ii) Inspired by the paper [21], we modify thealgorithm using an ingredient to capture stationary solutions. In all cases we ana-lyze a first- and second-order schemes and prove the unconditionally energy stability.We also provide an error analysis for the first-order scheme. Finally we validate ourschemes by performing simulations of the Kovasznay flow and double lid driven cav-ity flow. These flow simulations at high Reynolds numbers demonstrate the robustness and efficiency of the proposed schemes

Modern pharmacological studies have shown that Fructus Tribuli can improve sexual function and treat cardiovascular diseases. In this study, we focused on comparing the pharmacokinetics of crude Fructus Tribuli (CFT) and stir-fried Fructus Tribuli (SFT) to further clarify the changes in chemical composition in vivo. The quantitation of six analytes was performed in a triple quadrupole mass spectrometer using the multiple reaction monitoring mode. Separation was performed on a Halo® C18 column using 0.05% formic acid and 5 μmol/L sodium formate in water, and 0.05% formic acid and 5 μmol/L sodium formate in acetonitrile as the mobile phase. The selectivity, precision, accuracy, extraction recovery, matrix effect and stability of the method were fully validated. Compared with the crude group, the parameters Cmax and AUC0-t of terrestroside B and terrestrosin K increased significantly (P < 0.05), but the Cmax and AUC0-t of polianthoside D, terrestrinin D, tribuluside A and terrestrosin D were decreased, terrestrosin D being especially decreased (P < 0.05), after oral administration of SFT extract. These results showed that the developed method was suitable for pharmacokinetic analysis of the six steroid saponins of CFT and SFT in rat plasma, and can be used to facilitate future clinical studies.

An electrode made of loofah sponge derived activated carbon supported on nickel foam (AC/Ni) was successfully fabricated and used to remove ammonium ion (NH4+) from aqueous solution. A multilayer adsorption isotherm was used to describe ammonium electro-sorption on AC/Ni electrodes at different temperature, initial NH4+ concentration, and electrical field. The cyclic voltammetry (CV) results suggested that the electrical capacitance of AC/Ni electrodes, with the AC being prepared without preheating (OAC) or with low temperature heating (i.e., 300 AC), were higher than those prepared at high preheating temperature (i.e., 400 AC and 500 AC). Increasing the electro-sorption temperature from 10 to 50 °C decreased the monolayer NH4+ adsorption capacity from 5 to ca. 2–3 mg-N g−1, respectively. Background electrolyte, namely, sodium sulfate, exhibited significant competitive effect on the adsorption of ammonium ion at sodium ion concentration > 10−2 M. The activation energy and heat of adsorption were 9–23.2 kJ mol−1 and −3.7–−10.7 kJ mol−1, respectively, indicating a physisorption and exothermic adsorption characteristics. Based on the kinetics and thermodynamics analysis, there was slight increase in the activation energy with elevating preheating temperature, which increased the quantity of micro-pores and surface heterogeneity of the AC materials. Overall, results clearly demonstrated that carbon pyrolysis played a role on the capacitive charging behaviors of electrodes and the efficiency of NH4+ electro-sorption on the AC/Ni electrodes.

Sesquiterpanes are ubiquitous components of crude oils and ancient sediments. Liquid saturated hydrocarbons from simulated pyrolysis experiments on immature organic-rich mudstone collected from the Lower Cretaceous Hesigewula Sag were analyzed by gas chromatography–mass spectrometry (GC–MS). C14 bicyclic sesquiterpanes, namely, 8β(H)-drimane, 8β(H)-homodrimane, and 8α(H)-homodrimane were detected and identified on basis of their diagnostic fragment ions (m/z 123, 179, 193, and 207), and previously published mass spectra data, and these bicyclic sesquiterpanes presented relatively regular characteristics in their thermal evolution. The ratios 8β(H)-drimane/8β(H)-homodrimane, 8β(H)-homodrimane/8α(H)-homodrimane, and 8β(H)-drimane/8α(H)-homodrimane all show a clear upward trend with increasing temperature below the temperature turning point. Thus, all these ratios can be used as evolution indexes of source rocks in the immature–low-maturity stage. However, the last two ratios may be more suitable than the first ratio as valid parameters for measuring the extent of thermal evolution of organic matter in the immature–low-maturity stage because their change amplitude with increasing temperature is more obvious.

Tetrafluoroborate anion (BF4−) is found in the streams of flue-gas desulfurization and borosilicate glasses etching which deteriorates water quality through slow hydrolysis into boric acid and fluoride. Decomposition and electrocoagulation (EC) of BF4− were studied using metallic aluminum as the sacrificial electrode. The dissolved Al(III) from the anode could efficiently decompose BF4− in forms of fluoroaluminate complexes, and the derived boric acid and fluoride ion were removed by sweep flocculation. Major variables were investigated to optimize EC, including the reaction pH, initial concentration of BF4−, current density and electrolyte type. The mechanism of EC process was elucidated with the kinetics of consecutive reactions. Experimental results suggested that the removal of BF4− and total fluoride were less influenced by pH, and that of total boron reached a maximum at pH 8 which favored the surface complexation between borate species and EC precipitates. Under the conditions: [BF4−]0 = 9.3 mM, [NaCl] = 10 mM, pH = 8.0, current density = 5 mA/cm2, 98.3% of BF4− was decomposed and the removal of total fluoride and boron attained 98.2% and 74.1%, respectively within 3 h. EC using the Al electrode outperformed the conventional chemical coagulation and reduced the levels of BF4 , B(OH)3 and F− in aqueous solution synergically.

Solid/liquid interfaces are ubiquitous in nature and knowledge of their atomic-level structure is essential in elucidating many phenomena in chemistry, physics, materials science and Earth science1. In electrochemistry, in particular, the detailed structure of interfacial water, such as the orientation and hydrogen-bonding network in electric double layers under bias potentials, has a significant impact on the electrochemical performances of electrode materials2–4. To elucidate the structures of electric double layers at electrochemical interfaces, we combine in situ Raman spectroscopy and ab initio molecular dynamics and distinguish two structural transitions of interfacial water at electrified Au single-crystal electrode surfaces. Towards negative potentials, the interfacial water molecules evolve from structurally ‘parallel’ to ‘one-H-down’ and then to ‘two-H-down’. Concurrently, the number of hydrogen bonds in the interfacial water also undergoes two transitions. Our findings shed light on the fundamental understanding of electric double layers and electrochemical processes at the interfaces. Interfacial water structures in electric double layers under bias potentials can impact the electrochemical performance of electrodes. Two structural transitions of interfacial water at electrified Au single-crystal electrode surfaces have now been identified.

According to Bergmann’s rule, in endothermic species, body sizes of individuals tend to be larger in colder climates compared to those in warmer climates. Some ectotherms, including amphibians, have also been found to conform to this rule. However, the validity of this rule is disputed, as it is uncertain whether Bergmann’s clines are generally applicable to all anuran species. Here we studied altitudinal variation in mean body size, egg size, age, and growth rate in Bufo minshanicus across six altitudes in the eastern Tibetan Plateau. Our results showed that mean body size increased with increasing altitude, which is consistent with Bergmann’s rule. Toads from higher altitudes also tended to have faster growth rates and older mean ages of reproductively mature adults, but did not have larger egg sizes. We suggest that, as growth rate is positively correlated with altitude, and it contributes to body size variation more than mean age does, then this explains why this species follows Bergmann’s rule.

In this study, iron is removed from aqueous solution using a fluidized-bed crystallizer. Homogeneous oxyhydroxide pellets (FeOOH) were recovered at various value of pH, surface loading (L), and initial ferrous concentration to assess the treatability of iron-containing water. The optimal conditions for treating initial ferrous concentrations of 100–300 mg/L were L = 0.6 kg/m2/h (with 29 m/h of upflow velocity), a bed expansion of 50% and pH = 6.5 yielding the total iron removal (TR) of more than 99% and a corresponding iron crystallization ratio (CR) of 85%. X-ray diffractometry (XRD) revealed that the pellets consisted of a mixture of goethite (α-FeOOH) and lepidocrocite (γ-FeOOH). Scanning electron microscopy (SEM) yielded images of pellets of up to 1 mm in diameter, which were assembled from FeOOH flakes with thicknessess of 0.2–0.4 µm.

Colour fading is now a popular process used for imparting a vintage look to textile and fashion products, which enhances market value because of the current fashion trends. This study examined a non-aqueous colour fading process with the use of oxygen plasma-induced ozone treatment. An industrial scale machine and commercially available red sulpur-dyed cotton fabric (with 0.5 %, 1.5 % and 2.5 % colour depths) were used in this study. Since the colour fading process factors are inter-related to each other, a specific experiment approach, i.e. orthogonal method, was used for obtaining the optimum conditions in an industrial scale colour fading process. Three process factors used in the industrial scale colour fading process, i.e. (i) oxygen gas concentration (%); (ii) amount of water in fabric (%); and (iii) treatment time (minutes), would be studied in this paper. Through the orthogonal method, the optimum conditions for colour fading of the three colour depths of cotton fabric dyed by red sulphur dye were determined and their optimum conditions were same. The optimum conditions of the colour fading of the three colour depths were: (i) 70 % oxygen gas concentration; (ii) 35 % amount of water in fabric; and (iii) 30 minutes treatment time. Although colour fading conditions are the same, the order of importance of these process factors was different. Unlike the conventional colour fading process, oxygen plasma-induced ozone colour fading treatment can achieve uniform and even colour fading effect in the cotton fabric effectively.

Unprecedented hydroxy-alkynylation and -alkenylation reactions of arylalkenes have been developed through electrochemically enabled addition of an organotrifluoroborate reagent and H2O across the double bond of the alkene. The use of electrochemistry to promote these oxidative alkene 1,2-difunctionalization reactions not only obviates the need for transition-metal catalysts and oxidizing reagents but also ensures high regio- and chemoselectivity to afford homopropargylic or homoallylic alcohols. The possibility of extending the electrochemical alkene difunctionalization strategy to other alkene carbo-heterofunctionalization reactions has been demonstrated.

Magnetically separable spinel ferrites were created in an electrocoagulation (EC) process for removing boron from aqueous solution. Coprecipitates of NiFe2O4, CoFe2O4 and CuFe2O4 were obtained using sacrificial iron anodes (EC-Fe) in an electrolyte that contained transition metal salts (Ni, Co, Cu). The use of nickel chloride (NiCl2) as the supporting electrolyte yielded the highest boron removal since the maximum adsorption capacity of the resulting sludge was 28.9 mg-B/g. An EC that used iron and nickel as anodes (EC-Fe/Ni) in NaCl electrolyte was then employed to form nickel ferrite by electrochemical dissolution of ferrous (Fe(II)) and nickel (Ni(II)) ions, providing comparable removal efficiency but minimizing the residual level of Ni(II) in the treated water. The saturation magnetization of the precipitate that was produced in the EC-Fe/Ni system was 50.3 emu/g which exceeded that in the EC-Fe system with nickel chloride – 21.8 emu/g, indicating its outstanding magnetic separability. EC-Fe/Ni was optimized to remove 95% of boron from solution in 60 min with an initial boron concentration of 10 ppm at pH 8 and a current density of 3.75 mA/cm2.

The present study describes a method of using a nonlinear energy sink (NES) to realize vibration reduction of the flywheel system, and integrates the NES with the flywheel support structure consisting of a simply supported plate and the flywheels to achieve vibration control. In the micro-vibration environment of the laser communication satellite, the device is proposed on the vibration attenuation of the momentum wheel system. In the system, the external excitation consists of a superposition of several discrete sinusoidal harmonics generated by the radial micro-vibration of the flywheel. A finite-element model is developed and then verified by the equivalent model results. The governing equations of the plate are discretized via the Galerkin method. The complexification-averaging (CX-A) method is employed to obtain approximate solutions. The amplitude-frequency responses of the system are obtained. The vibration suppression of the system is analyzed, and the approximate solutions are verified by numerical results. To systematically analyze the dynamic behaviors of the designed nonlinear vibration absorber, different parameters are selected for NES, and saddle-node bifurcations and Hopf bifurcations are obtained by selecting some specific parameters. The RMS ratio of the transmitted force to the excitation force is used to calculate the transmissibility of the system equipped with the NES. A parametric study is conducted for further optimization. Results illustrate that NES has a good vibration reduction effect on the micro-vibration of the system.

The imidacloprid was mineralized by heterogeneous photo-Fenton process in a three-phase fluidized bed reactor using waste iron oxide as catalyst. The effects of catalyst loading, dosage of H2O2 and...

Ostrinia furnacalis (Lepidoptera: Pyralidae) is one of the most destructive agricultural pests in Asia. Traditional pest-management methods include sex pheromone capture, transgenic crops that produce Bacillus thuringiensis toxin, and pesticides. Although these strategies control pest populations effectively, they also cause negative side effects, including dramatically increased pesticide resistance, severe pollution, and hazards for human health. Recently developed genome editing tools provide new prospects for pest management and have been successfully used in several species. However, few examples have been reported in the agricultural pest O. furnacalis due to a lack in genomic information. In this report, we identified only one transcript of O. furnacalis Argonaute 1 (OfAgo1) gene from the genome and cloned the open reading frame. OfAgo1 presented the maximum expression at the embryo stage or in the fat body during the larval stages. To understand its function, an OfAgo1 mutant was constructed using the Clustered Regularly Interspaced Short Palindromic Repeat/RNA-guided Cas9 nuclease (CRISPR/Cas9). Mutagenesis of OfAgo1 disrupted cuticle pigmentation by down-regulating micro RNAs and pigmentation-related genes. This is the first report for the cloning and functional analysis of OfAgo1, revealing a role of OfAgo1 in cuticle pigmentation. The current report also established a CRISPR/Cas9 system in O. furnacalis, providing a new insight for pest management.

A nickel foam-supported Ni(OH)2/NiOOH electrode, synthesized in-situ at a specific electrode overpotential, was used to study the oxidation of ammonia in aqueous solution. Results of voltammetric analysis showed the formal potential of Ni(OH)2/NiOOH transition at +0.6 V (vs. Hg/HgO, pH 11) at which the current profile was improved by electron transfers of NH3 in the electrolyte. Selectivity of NH3 conversion to NO3− and N2 was evaluated by batch constant current experiments. Electrochemical parameters, including solution pH (6–12), temperature (20–40 °C), current density (0.2–3 mA cm−2), and initial NH3-N concentration (20–450 mg-L−1), that may affect ammonia oxidation toward nitrogen selectivity were studied. At constant current density of 1.5 mA cm−2A, ammonia removal reached 98.5% and NO3− was the major product at initial NH3-N concentration of 50 mg-L−1 in 7 h. By contrast, N2 evolution dominated at low current density ( 100 mg-L−1). A surface steady-state approach, with NH3 deprotonation as the rate-limiting step, provided the reaction pathways of NH3 conversion to molecular nitrogen byproduct.

This study presents a noncontact measurement of biological tissues with the elimination of curved-surface air gap using a triple-ring complementary split-ring resonator (CSRR). The resonance frequency deviations are accessed to measure the thickness of the material under test (MUT), with multiple estimations to reduce the errors. An equivalent mapping is proposed to convert the curved-surface boundary to a simplified uniform air-gap method. The accuracy of the thickness measurement of the MUT improves under the existence of unknown curved air gap. This paper proposes a low-cost CSRR to measure the thickness of a curved porcine fat. The average absolute errors of measured results of a 3-mm porcine fat is 1.43 mm, which is acceptable for a lossy curved, rough-surfaced material. The provided technique shows an excellent solution of eliminating the influence of non-planar surface on measurement.

Plasmonic random lasers have been demonstrated in combining dye-doped cholesteric liquid crystals (DD-CLCs) and silver nanoparticles (AgNPs). The DD-CLC laser reveals the lowest threshold and highest slope efficiency through the localized surface plasmon resonance of AgNPs with the best coupling of the emission spectrum of lasing dye and resonance of electron oscillation on the metal surface. Thermal control of the DD-CLC lasers has been achieved to simultaneously shift the long- and short-edge lasing peaks. By the α -stable analysis, the DD-CLC random laser (RL) reveals heavy tail distribution with relatively low α ∼ 1.06 to show the Lévy behavior. Owing to its low spatial coherence, the DD-CLC RL has been demonstrated to produce a speckle-reduced image with a lower contrast of about 0.04.

The main objective of this research is to investigate the permanent deformation of asphalt mixtures containing direct coal liquefaction residue (DCLR) under various tire pressures and temperatures. Three types of asphalt mixtures, including control/DCLR/composite-DCLR modified asphalt mixture, were prepared by the Marshall design method. The rutting test was conducted under a tire pressure range of 0.7–1.0 MPa with a 0.1-MPa interval and at a temperature range of 55–70°C with a 5°C interval. Moreover, the dynamic stability and rutting depth of three asphalt mixtures were obtained to evaluate their resistance of permanent deformation. It was found that the rutting resistance of three asphalt mixtures declines with the increased tire pressures and temperatures. The asphalt mixture containing DCLR has a higher dynamic stability and lower rutting depth compared to the control asphalt mixture under the same conditions. Furthermore, the rutting resistance of composite-DCLR modified asphalt mixture is better than that of DCLR modified asphalt mixture. It indicates that the composite-DCLR is favorable for the improvement of rutting resistance of asphalt mixture. Moreover, the analysis of variance was applied, which analysis results showed that the rutting resistance of asphalt mixture is more sensitive to temperature than tire pressure. Based on the least-squares procedure, the relationship between dynamic stability and rutting depth was obtained, and the accuracy of the prediction is acceptable.

The anthropogenic emission of boron to river has become a serious problem that deteriorates the water quality and endangers the ecosystem. Although boron is a micronutrient, it is toxic to plants, animals and humans upon exposure. In this review, we first present the sources of the boron-containing streams and their composition, and then summarize the recent progress of boron removal methods based on adsorption and coagulation systematically. The boron-spiked streams are produced from coal-fired and geothermal power plants, the manufacturing and the activities of oil/gas excavation and mining. The adsorbents for boron removal are classified into the ones functionalized by chelating groups, the ones on the basis of clays or metal oxide. Three subgroups reside in the coagulation approach: electrocoagulation, chemical precipitation and chemical oxo-precipitation. The hybrid technology that combines membrane process and adsorption/coagulation was covered as well. To provide a comprehensive view of each method, we addressed the reaction mechanism, specified the strength and weakness and summarized the progress in the past 5 years. Ultimately, the prospective for future research and the possible improvement on applicability and recyclability were proposed.

Transplantation of submerged macrophytes to restore shallow lakes has been used as an effective measure to maintain a clear water state. Water quality is highly correlated with submerged macrophytes community, however, the relationships between water quality and the diversity, coverage and biomass of submerged macrophytes are, so far, not yet well studied. We analyzed the correlations of nutrient concentrations, water clarity and phytoplankton biomass with the metrics of submerged macrophytes community in two Chinese restored shallow subtropical lakes, Lake Wuli (Wuli-E, 5 ha) and Lake Qinhu (Qin-E, 8 ha). A similar biomass of submerged macrophytes was transplanted into each lake, while both the species richness and coverage of macrophytes in Qin-E were lower than Wuli-E. After a 1&ndash, 2-year restoration, the diversity almost had no change, but the biomass density and coverage decreased in Wuli-E. As for Qin-E, the coverage of submerged macrophytes increased but biomass density and diversity decreased. The dominance of canopy-forming submerged macrophyte species Myriophyllum spicatum was observed in Qin-E and less meadow-forming biomass and species was observed than that in Wuli-E. Moreover, it was also observed that Wuli-E had a better water quality than that of Qin-E after transplantation. Path analysis results showed that macrophyte coverage and the diversity related to meadow-forming species (e.g., Vallisneria spinulosa) had strong effects on enhancing clarity and reducing nutrient concentrations. But the high biomass density accompanied by the canopy-forming species like M. spicatum was unfavorable for controlling nutrients. Our results provide important insight into the different roles that macrophyte diversity, biomass and coverage play in improving water clarity and controlling nutrient concentrations. This new knowledge will be instrumental in implementing more effective lake restoration, especially using macrophyte transplantation as a restoration tool in warm shallow lakes.

Demethylation is a chemical process widely distributed in nature to remove a methyl group from an organic molecule, which is a key aspect of diverse biological processes including biosynthesis of natural products, degradation of plant biomass and epigenetic regulation. This process is facilitated by diverse demethylases via distinct mechanisms. Recent studies have disclosed some novel demethylation reactions as well as their underlying demethylases in the biosynthesis of bacterial sterols, fungal terpenoids, and plant alkaloids. This article focuses on current advances in dissecting the demethylation reactions in biosynthesis of natural products and aims to point out the enzymatic mechanisms, which will further enhance our knowledge and understanding of demethylation process in nature.

Despite rapid progress in the power-conversion efficiency of $\mathrm{Pb}$-based perovskite solar cells, both the long-term instability and $\mathrm{Pb}$ toxicity are still the main challenges for their commercial applications. Here, by first-principles $GW$ calculations, we find three kinds of two-dimensional (2D) 111-type $\mathrm{Pb}$-free $\mathrm{In}$-based halide perovskites of the form ${\mathrm{Cs}}_{3}{\mathrm{In}}_{2}{X}_{9}\phantom{\rule{0.2em}{0ex}}(X=\mathrm{Cl},\mathrm{Br},\mathrm{I})$ as promising alternatives to the star material ${{\mathrm{CH}}_{3}{\mathrm{NH}}_{3}\mathrm{Pb}\mathrm{I}}_{3}$ (${\mathrm{MA}\mathrm{Pb}\mathrm{I}}_{3}$) because of the following excellent electronic, optical, and transport properties: (i) The 2D $\mathrm{In}$-based halide perovskites are environmentally friendly lead-free materials. (ii) Compared with $\mathrm{MA}\mathrm{Pb}{X}_{3}$, they have greater structural stability. (iii) As energetic photovoltaic materials, 2D ${\mathrm{Cs}}_{3}{\mathrm{In}}_{2}{\mathrm{I}}_{9}$ perovskites are direct-band-gap semiconductors with optimal band gaps from 1.25 eV (trilayer) to 1.47 eV (monolayer). (iv) The 2D ${\mathrm{Cs}}_{3}{\mathrm{In}}_{2}{X}_{9}$ perovskites have ideal band structures for solid-state lighting with a wide direct-optical-band-gap range (approximately 0.94--3.54 eV), covering the whole visible-light region, and light electron (heavy hole) effective mass, which will directly enhance the defect-insensitive emission efficiency due to the localization of holes. Particularly, ${\mathrm{Cs}}_{3}{\mathrm{In}}_{2}{\mathrm{Br}}_{x}{\mathrm{Cl}}_{9\ensuremath{-}x}$ has a suitable direct optical band gap for highly desired blue emission. (v) The absorption coefficient of ${\mathrm{Cs}}_{3}{\mathrm{In}}_{2}{X}_{9}$ is up to $7\ifmmode\times\else\texttimes\fi{}{10}^{4}\phantom{\rule{0.2em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$, which is between that of $\mathrm{Ga}\mathrm{As}$ (${10}^{4}\phantom{\rule{0.2em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$) and that of ${\mathrm{MA}\mathrm{Pb}\mathrm{I}}_{3}$ (${10}^{5}\phantom{\rule{0.2em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$). (vi) The estimated power-conversion efficiency in ${\mathrm{Cs}}_{3}{\mathrm{In}}_{2}{\mathrm{I}}_{9}$ reaches 28%, which is close to that of ${\mathrm{MA}\mathrm{Pb}\mathrm{I}}_{3}$ (30%). These findings pave a way for designing nontoxic, stable, and high-performance photovoltaic and light-emitting devices.

The investigation of substrate spectrum towards five racemic (rac-) aryl glycidyl ethers (1a–5a) indicated that E. coli/pveh3, an E. coli BL21(DE3) transformant harboring a PvEH3-encoding gene pveh3, showed the highest EH activity and enantiomeric ratio (E) towards rac-3a. For efficiently catalyzing the kinetic resolution of rac-3a, the activity and E value of PvEH3 were further improved by site-directed mutagenesis of selected residues. Based on the semi-rational design of an NC-loop in PvEH3, four single-site variants of pveh3 were amplified by PCR, and intracellularly expressed in E. coli BL21(DE3), respectively. E. coli/pveh3E134K and /pveh3T137P had the enhanced EH activities of 15.3 ± 0.4 and 16.1 ± 0.5 U/g wet cell as well as E values of 21.7 ± 1.0 and 21.2 ± 1.1 towards rac-3a. Subsequently, E. coli/pveh3E134K/T137P harboring a double-site variant gene was also constructed, having the highest EH activity of 22.4 ± 0.6 U/g wet cell and E value of 24.1 ± 1.2. The specific activity of the purified PvEH3E134K/T137P (14.5 ± 0.5 U/mg protein) towards rac-3a and its catalytic efficiency (kcat/Km of 5.67 mM−1 s−1) for (S)-3a were 1.7- and 3.54-fold those (8.4 ± 0.3 U/mg and 1.60 mM−1 s−1) of PvEH3. The gram-scale kinetic resolution of rac-3a using whole wet cells of E. coli/pveh3E134K/T137P was performed at 20 °C for 7.0 h, producing (R)-3a with 99.4% ees and 38.5 ± 1.2% yield. Additionally, the mechanism of PvEH3E134K/T137P with remarkably improved E value was analyzed by molecular docking simulation.

Background Epoxide hydrolase can regioselectively catalyze the oxirane ring-opening hydrolysis of rac-epoxides producing the corresponding chiral diols. In our laboratory, a gene named pveh1 encoding an EH from Phaseolus vulgaris was cloned. Although the directed modification of PvEH1 was carried out, the mutant PvEH1Y3 showed a limited degree of enantioconvergence towards racemic (rac-) m-chlorostyrene oxide (mCSO). Results PvEH1 and PvEH1Y3 were combinatively subjected to laboratory evolution to further enhance the enantioconvergence of PvEH1Y3 towards rac-mCSO. Firstly, the substrate-binding pocket of PvEH1 was identified using a CAVER 3.0 software, and divided into three zones. After all residues in zones 1 and 3 were subjected to leucine scanning, two E. coli transformants, E. coli/pveh1Y149L and /pveh1P184L, were selected, by which rac-mCSO was transformed into (R)-m-chlorophenyl-1,2-ethanediol (mCPED) having 55.1% and 27.2% eep. Secondly, two saturation mutagenesis libraries, E. coli/pveh1Y149X and /pveh1P184X (X: any one of 20 residues) were created at sites Y149 and P184 of PvEH1. Among all transformants, both E. coli/pveh1Y149L (65.8% αS and 55.1% eep) and /pveh1P184W (66.6% αS and 59.8% eep) possessed the highest enantioconvergences. Finally, the combinatorial mutagenesis was conducted by replacements of both Y149L and P184W in PvEH1Y3, constructing E. coli/pveh1Y3Z2, whose αS reached 97.5%, higher than that (75.3%) of E. coli/pveh1Y3. In addition, the enantioconvergent hydrolysis of 20 mM rac-mCSO was performed by E. coli/pveh1Y3Z2, giving (R)-mCPED with 95.2% eep and 97.2% yield. Conclusions In summary, the enantioconvergence of PvEH1Y3Z2 was successfully improved by laboratory evolution, which was based on the study of substrate-binding pocket by leucine scanning. Our present work introduced an effective strategy for the directed modification of enantioconvergence of PvEH1.

A new complex [(CH3)3NH]2[Co(NCS)4], in which zero-dimensional [Co(NCS)4] n 2− anions are balanced by 2n [(CH3)3NH]+ cations, was synthesized. The complex has been characterized by single X-ray diffraction, infrared spectroscopy, elemental analysis, and magnetic measurements. Magnetic susceptibility data indicate ferromagnetic interactions among the CoII ions.

Within the framework of the spin-polarized density-functional theory , we have studied the electronic and magnetic properties of InSe/black-phosphorus (BP) heterostructure doped with 3d transition-metal (TM) atoms from Sc to Zn. The calculated binding energies show that TM-atom doping in the van der Waals (vdW) gap of InSe/BP heterostructure is energetically favorable. Our results indicate that magnetic moments are induced in the Sc-, Ti-, V-, Cr-, Mn- and Co-doped InSe/BP heterostructures due to the existence of non-bonding 3d electrons. The Ni-, Cu- and Zn-doped InSe/BP heterostructures still show nonmagnetic semiconductor characteristics. Furthermore, in the Fe-doped InSe/BP heterostructure, the half-metal property is found and a high spin polarization of 100% at the Fermi level is achieved. The Cr-doped InSe/BP has the largest magnetic moment of 4.9 μB. The Sc-, Ti-, V-, Cr- and Mn-doped InSe/BP heterostructures exhibit antiferromagnetic ground state. Moreover, the Fe- and Co-doped systems display a weak ferromagnetic and paramagnetic coupling, respectively. Our studies demonstrate that the TM doping in the vdW gap of InSe/BP heterostructure is an effective way to modify its electronic and magnetic properties.

The Q-switched pulse and mode-locked pulse were investigated in an all-normal dispersion Yb-doped fiber laser (YDFL) based on the topological insulators (TIs) with mixing of polyvinyl alcohol (PVA) to produce Bi2Se3 /PVA film or deposition on the end facet of fiber to manufacture TI-compatible fiber. Through the dark Bi 2Se3/PVA films with large nonsaturable loss, the YDFL was operated in the Q-switched state. The repetition rate and the duration of the Q-switched pulses increased and declined, respectively, with the pump power to show 2.2 μs duration and 137.8 kHz repetition rate at the highest pump power. Moreover, the mode-locked pulses, with a 16 MHz repetition rate and 380 ps pulsewidth, were generated at high pump power by using the light Bi2Se3/PVA film. By means of a Bi2Se3 compatible fiber, through optical deposition of the Bi2Se3 nanoplatelets on the end facet of the fiber, the mode-locked YDFL was generated at low-threshold pump power and revealed more stabilized operation state up to two hours.

In this work, the structure, electronic, elastic, elastic anisotropy, thermoelectric, and thermodynamic properties of CaMgSi under pressure are calculated via first-principles methods. The optimized structure and lattice parameters are in agreement with previously published experimental results, indicating the methods used in this work are feasible and reliable. The calculated results show that the values of bulk modulus, B, Young’s modulus, E, and shear modulus, G, increase with the pressure overall, while the values of G and Y decrease in special pressure regimes from 20 to 24 GPa. Analyses of Poisson’s ratio, v, and Pugh’s modulus ratio, B/G, imply that CaMgSi is prone to change from brittle to ductile with increasing pressure. The transition from brittleness to ductility occurs at a pressure of 16 GPa. The value of Hv decreases with the pressure overall, although it increases over the pressure ranges of 16–20 GPa and 24–28 GPa. Universal elastic anisotropy increases at pressures from 4 to 24 GPa, while it decreases over the pressure ranges from 0–4 and from 24–28 GPa. Moreover, the variation of elastic anisotropy for G and E is larger compared to that of B. In addition, the electrical conductivity and electronic thermal conductivity decrease with increasing pressure based on the total density of states for CaMgSi. In addition, the heat capacity decreases with increasing pressure, indicating the reduction of lattice thermal conductivity, which is beneficial for thermoelectric performance, especially at pressures from 8 to 16 GPa. Meanwhile, the structural stability can be enhanced at higher pressures, while the thermal stability of crystalline CaMgSi becomes weaker with increasing pressure. The investigation presented in this work offers a comprehensive understanding of the effects of pressure on the mechanical, thermoelectric, and thermodynamic properties of CaMgSi, which can provide guidance for further theoretical work and practical applications.

Gas chromatography/mass spectrometry (GC/MS) can only analyze volatile molecular compounds, and it has limitations when applied to determine the complex components of crude oils and hydrocarbon source rocks. Based on Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and GC/MS analyses, the molecular compositions of NSO compounds in extracts from the Permian Dalong Formation, Sichuan Basin and the Permian Lucaogou Formation, Junggar Basin in China were compared. Analyses of types of heteroatoms present (S1, S2, S3, OS, OS2, O2S, NS, and NOS compounds) suggest that marine shales from the Dalong Formation are mainly composed of carboxylic acids (O2 compounds) with a high abundance of fatty acids, indicating a marine phytoplankton organic source. However, lacustrine shales from the Lucaogou Formation are dominated by pyrrolic compounds (N1 compounds) with abundant dibenzocarbazole. It suggests that the organic source materials may be derived from lower aquatic organisms and lacustrine algae. Overall, FT-ICR-MS has potential for applications in analyses and determination of depositional environments and organic sources in petroleum geology.

A new coordination network based on 5-(1H-benzoimidazol-2-ylsulfanylmethyl)-isophthalic acid (H2bismip) along with 4,4-bis(1-imidazolyl)bibenzene (bimb), formulated as [Ni2(bismip)2(bimb)2(H2O)]n (1) has been synthesized under solvothermal condition. Compound 1 has been structurally characterized by elemental analysis, IR spectroscopy, powder X-ray diffraction (PXRD). Single crystal X-ray diffraction analysis shows compound 1 is a 2D network with a Schlafli symbol of 44. The layer framework exhibits effective adsorption on organic dye. The kinetic of the adsorption process was analyzed by the pseudo-first-order and pseudo-second-order model equations and the data was fitted well with the pseudo-second-order kinetic model (R > 0.99). The compound was found to be an excellent selective absorbent for the removal of methyl orange (MO) from the mixture solution of methyl orange - methylene blue (MO-MB).

Chemical oxo-precipitation (COP) is a modified precipitation process in which hydrogen peroxide is used to transform boric acid to perborate anions, which are precipitated with calcium salt under ambient conditions. To minimize the production of sludge, chemical oxo-precipitation was performed in a fluidized-bed reactor to reclaim boron as unseeded calcium perborate pellets. Several major experimental parameters, including effluent pH, calcium dosage, and surface loading that affected the degree of supersaturation and the efficiency of boron removal, were tested. A crystallization ratio of around 60% was attained under the following conditions: initial boron concentration = 1000 ppm, molar ratios of [Ca]/[B] = 0.6 and [H2O2]/[B] = 2, effluent pH = 10.6, bed height = 80 cm, and hydraulic retention time = 18 min. On the basis of the characterization of XRD, SEM, and Raman spectroscopy, the granules recovered were amorphous calcium perborates Ca(B(OH)3OOH)2 and CaB(OH)3OOB(OH)3.