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In the investigation of criminal cases involving metallic weapons such as firearms and knives, the trace metal detection test (TMDT) and the transfer detection technique are two effective and on-the-spot methods to link a suspect and a suspected metallic weapon. In general, these tests need to be conducted on suspects' hands or done by lifting trace metals from their hands within 3 days of the crime being committed. However, if no suspects are arrested within this period, neither of these two techniques is applicable. This paper presents preliminary development of a modified TMDT to overcome the intrinsic disadvantages of conventional TMDTs. The method primarily focuses on the secondary imprints on porous substrates that are transferred unconsciously from the palms of criminals after handling galvanized weapons. The modified TMDT was established by studying the effect of various factors on secondary imprints on porous substrates. We also tested the effectiveness of the modified TMDT for common porous substrates and galvanized weapons and its relative sensitivity in a depletion series. Additionally, the storage conditions of the developed secondary imprints as physical evidence were studied under different time lapses and light conditions. Finally, we proposed an improved procedure for detecting metal traces formed in the use of metallic weapons and subsequent activities at a crime scene. The modified TMDT provides a novel method for investigators to demonstrate the relationship between a suspect and a metallic weapon, thus reducing the heavy reliance of conventional TMDTs on suspects and the time limit available to visualize or lift metal traces. For this reason, it can be used as a complementary and remedial method for conventional TMDTs, especially when suspects are not arrested within 3 days of the commission of a crime. Furthermore, the improved procedure can serve as a guide for investigators to apply the TMDT series properly to solving the cases involving metallic weapons. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient SERS detection of morphine in solutions is achieved with a solid chip. • The special structure of the Au-SNCA chip makes it have excellent SERS performance. • The chip can be used to identify morphine homologues and broad-spectrum detect drugs. Rapid and flexible detection or accurate recognition of trace drugs is of great importance in cracking down on drug crimes, but it remains to be expected. Here, a solid chip is presented for the efficient detection and recognition of trace opioids (typically morphine) in aqueous solutions based on surface-enhanced Raman spectroscopy (SERS). Firstly, a Au-coated Si nano-cone array (Au-SNCA) is designed and fabricated via Si-based organic colloidal template etching and Au deposition. This Au-SNCA shows three-dimensional nanostructure with high densities of nanotips and deep nanogaps as well as high structural consistency, which exhibits strong SERS activity to morphine and outstanding stability. Then, such Au-SNCA is used as solid SERS chip to detect morphine in aqueous solutions. It has been demonstrated that using such solid chip, trace morphine in solutions could be recognized and detected within 1 min, and the detection limit is 10-5 mg/mL (∼10 ppb), showing rapid and sensitive detection, which is much better than the previous reports. Meanwhile, the Au-SNCA chip also can be utilized to detect trace morphine in tap water and reservoir water, the recoveries range from 90.4% to 102.4%. Such excellent SERS performance of this Au-SNCA chip is attributed to its special structure which enhances not only local electromagnetic field but also molecular adsorption. The experimental results about the effects of immersion time and concentration show that the adsorption behavior of morphine molecules on such Au-SNCA chip can be explained by the pseudo-second-order kinetic model and Freundlich adsorption mode. Moreover, the Au-SNCA chip is also suitable for the identification of morphine homologues and the broad-spectrum detection of various common drugs. This study presents a practical solid chip and a simple approach for the efficient SERS detection and recognition of trace drugs in solutions. This is of significance to on-site detect drugs in forensic science. [ABSTRACT FROM AUTHOR]

Abstract: The mm-sized capsule catalyst Co/SiO2-Z with the H-type zeolite (HZSM-5) as the shell, and the Co/SiO2-Z-Sp-Pd capsule catalyst with Pd loaded by sputtering method, as well as the Co/SiO2-Z-IW-Pd capsule catalyst, loading the Pd by incipient wetness impregnation, were prepared and used for isoparaffin direct synthesis by Fischer–Tropsch synthesis reaction from syngas with H2/CO ratio of 2/1 at 1.0MPa and 533K. The analysis results of XRD, SEM, EDS and NH3-TPD showed that a compact HZSM-5 shell was formed on the Co/SiO2 pellet, and the metallic Pd was well sputtered on the surface of the HZSM-5 shell for the Co/SiO2-Z-Sp-Pd catalyst. The isoparaffin and olefin selectivity increased in the FTS reactions on the HZSM-5 capsule catalyst than on the Co/SiO2 catalyst. The selectivity of isoparaffins increased, and the selectivity of olefins decreased when using the Co/SiO2-Z-Sp-Pd catalyst, compared with the Co/SiO2-Z catalyst or the Co/SiO2-Z-IW-Pd catalyst, because metallic Pd introduced by sputtering on the zeolite shell could hydrogenate olefins efficiently. It was suitable to use the sputtering method for the preparation of the zeolite capsule catalyst loaded with metallic Pd, as conventional impregnation method could not reduce Pd cation due to the strong interaction from zeolite surface. The CO conversion, CH4 and CO2 selectivity on the catalyst of Co/SiO2-Z-Sp-Pd increased with temperature increasing from 513K to 553K. At elevated temperature, the isoparaffin selectivity also increased while the olefin selectivity was suppressed. [Copyright &y& Elsevier]

Abstract: The CO2 reforming reaction of CH4 was conducted by using a Ni-based catalyst prepared by the co-impregnation method. The properties of the catalysts and the carbon deposition performance on the catalyst surface were surveyed by XRD, TPR, TG-DTA, and SEM. The results showed that the activity of the Ni/γ-Al2O3 catalyst with Ni loading of 10% was higher than that of those with other Ni loadings. However, the Ni/γ-Al2O3 catalyst was not stable in the continuous reaction due to a large amount of carbon deposition on the catalyst surface. Although the activity of Ni/γ-Al2O3 with the La2O3 and CeO2 as promoters was not obviously increased, the carbon deposition on Ni/γ-Al2O3 with La2O3 and CeO2 as promoters was greatly suppressed in the CO2 reforming reaction of CH4. The amount of carbon deposition on the 10%Ni/3%CeO2–3%La2O3–γ-Al2O3 catalyst was reduced 76.2% compared with the 10%Ni/γ-Al2O3 catalyst, due to alkaline function and dispersion enhancement of La2O3–CeO2, as well as the electronic interactions between CeO2 and Ni. The results of SEM showed that the moss-like carbon on the 10%Ni/γ-Al2O3 catalyst was not easily gasified with CO2 and Ni particles, which would result in the catalyst deactivation. On the other hand, the filamentous carbon on the 10%Ni/3%CeO2–3%La2O3–γ-Al2O3 catalysts could be eliminated readily by gasifying with CO2. Because of the suppression in the sintering of Ni particles and the dominant formation of the reactive filamentous carbon on the Ni-based catalyst that included La2O3 and CeO2 promoters, 10%Ni/3%CeO2–3%La2O3–γ-Al2O3 catalyst showed stable activity in the continuous CO2 reforming reaction of CH4 at 1073K and atmospheric pressure. [Copyright &y& Elsevier]

Abstract: A new synthesis method of low-temperature methanol proceeded on Cu/ZnO/Al2O3 catalysts from CO/CO2/H2 using 2-butanol as promoters. The Cu/ZnO/Al2O3 catalysts were prepared by co-impregnation of r-Al2O3 with an aqueous solution of copper nitrate and zinc nitrate. The total carbon turnover frequency (TOF), the yield and selectivity of methanol were the highest by using the Cu/ZnO/Al2O3 catalyst with copper loading of 5% and the Zn/Cu molar ratio of 1/1, which precursor were not calcined, and reduced at 493K. The activity of the catalysts increased due to the presence of the CuO/ZnO phase in the oxidized form of impregnation Cu/ZnO/Al2O3 catalysts. The active sites of the Cu/ZnO/Al2O3 catalyst for methanol synthesis are not only metallic Cu but also special sites such as the Cu–Zn site, i.e. metallic Cu and the Cu–Zn site work cooperatively to catalyze the methanol synthesis reaction. [Copyright &y& Elsevier]

Abstract: Mechanism and kinetics of catalytic process for a new low-temperature methanol synthesis on Cu/ZnO catalysts from syngas (CO/CO2/H2) using catalytically active alcohol promoters were investigated by in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Two intermediate species, adsorbed formate species and alkyl formate species, were formed in this synthesis process. The adsorbed formate species easily reacted with ethanol or 2-propanol at 443K and atmospheric pressure, and the reaction rate with 2-propanol was faster than that with ethanol. Alkyl formate was readily reduced to form methanol at 443K and 1.0MPa, and the hydrogenation rate of 2-propyl formate was found to be quicker than that of ethyl formate. As a promoter, 2-propanol exhibited a higher activity than ethanol in the reaction of the low-temperature methanol synthesis. [Copyright &y& Elsevier]

Abstract: In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) was used to study the reaction mechanism of the formate adsorbed species with ethanol to form the ethyl formate on Cu/ZnO catalyst surface in a novel low-temperature methanol synthesis process. The results indicate that the formate adsorbed species were firstly formed by CO/CO2/H2 adsorbed on Cu/ZnO catalyst, followed by rapid reaction with ethanol to form ethyl formate. It was found that the species reacted with formate adsorbed species were ethanol in gas phase rather than adsorbed ethoxy species. The reaction of the adsorbed formate species with ethanol on Cu/ZnO catalyst surface proceeded according to Rideal-type mechanism, not Langmuir–Hinshelwood mechanism. [Copyright &y& Elsevier]

Abstract: A simple, rapid and relatively solventless method for extraction of objective compounds would be useful for forensic, judicial and clinical purposes. Solid phase micro-extraction membrane (SPMEM) is one such extraction technique that integrates sampling, extraction and concentration into a single step, and combines the advantages of both the solid phase micro-extraction (SPME) and membrane separation. In this study, a new kind of membrane was prepared using polyamide and Tenax compounds, and applied to solid phase micro-extraction. Characteristics of the membrane such as adsorption capacity were tested. Extraction conditions such as adsorption time, desorption solvents, desorption time and assisted desorption treatment methods were studied and optimized. Tetrahydrocannabinol (THC) and cannabidiol (CBD) in blood and brain of the injected male mice, and in spiked human urine were extracted using this solid phase micro-extraction membrane method. The extracted THC and CBD were further determined with LC–MS using APCI. Ions analyzed in single ion monitoring mode were 315 for THC and CBD, and 318 for the deuterated THC internal standard. [Copyright &y& Elsevier]

Abstract: In situ diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS) was used to clarify the reaction mechanism of a new methanol synthesis method on a Cu/MgO catalyst at 443K from syngas containing CO2 using an ethanol promoter. The adsorbed formate species were formed by exposing Cu/MgO catalyst to syngas (CO/CO2/H2), and it reacted easily with ethanol to form ethyl formate in two states: gas-phase species and physisorbed species, at low temperature. The ethyl formate was the reactive intermediate, and it was reduced easily by hydrogen atoms on Cu to form methanol at low temperature. The reaction temperature was significantly decreased due to the promotional catalytically active action of ethanol. This is a new reaction route, as ethanol used in this reaction was not consumed due to its self-regeneration by hydrogenation of ethyl formate. In order to accelerate this reaction, one must introduce a large amount of ethanol into the reaction system. [Copyright &y& Elsevier]

Abstract: In situ diffuse reflectance infrared Fourier-transform spectroscopy was used to clarify the reaction mechanism of a new methanol synthesis method on a Cu/ZnO catalyst at low temperature such as 423K from syngas containing CO2 and H2O using a 2-propanol promoter. The formate species was formed by exposing Cu/ZnO catalyst to syngas, and it easily reacted with 2-propanol to form a 2-propyl formate species at low temperature. 2-Propyl formate was then quickly reduced to form methanol and 2-propanol. The Cu/ZnO catalyst was active for all these steps while catalytically cycled 2-propanol realized a low-temperature route. [Copyright &y& Elsevier]

In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) was used to study the reaction mechanism of a new methanol synthesis method on Cu/ZnO at low temperatures from syngas (CO/CO2/H2) using ethanol promoter. The adsorbed formate species were formed by exposing Cu/ZnO catalysts to syngas (CO/CO2/H2), and it reacted easily with ethanol in the gas phase to form ethyl formate in two states of species, gas phase and physisorbed, at low temperatures. Ethyl formate was the reactive intermediate, and it was reduced easily by hydrogen atoms on Cu to form gas-phase methanol. The reaction temperature was significantly decreased due to the catalytic action of ethanol and a new reaction route. In order to accelerate this reaction, a large amount of ethanol must be introduced into the reaction system. When there was no ethanol or little ethanol in the reaction system, this reaction was difficult to complete at a temperature as low as 443 K. [Copyright &y& Elsevier]

Liquid–liquid or solid phase extraction methods are widely used for isolating analytes from urine, blood and other samples. But the preparation procedures of the samples are laborious, intensive, and costly. In addition, the organic solvents used are toxic to both the human body and the environment. An accurate, simple and rapid method for analysis of some compounds is required for forensic, judicial, and clinical purposes. Solid phase micro-extraction membrane (SPMEM) is a new, simple and solventless preparation technique. It integrates sampling, extraction and concentration into a single step and has the advantages of both the solid phase micro-extraction (SPME) and membrane separation.In this paper, a new kind of membrane used for the solid phase micro-extraction was prepared with amide compounds. The extraction conditions such as adsorption time, desorption solvents, methods and time are studied and optimized. The dichlorvos in the blood, morphine and phenobarbital in the urine were perfectly separated by using this solid phase micro-extraction membrane, and were tested by gas chromatograph–mass spectrometer (GC–MS). All the data were acquired in scan mode except that of morphine which was obtained in a selected ion monitoring (SIM) mode. Ions used for identification were those with m/z 57, 115, 162, 215, 285. [Copyright &y& Elsevier]

Considering the high use of inkjet printing in forgery cases, the classification of inkjet printing is particularly important in questioned document examination. In this work, a universal GC-MS method has been developed to analyze various ink components extracted from inkjet printouts. The results indicated that several components detected and identified across 195 inks could be used to distinguish printer manufacturers. A trend of decreasing solvent concentration over time was observed through the continuous monitoring of 7 samples. The results shown that this method is useful for forensic classification purposes, and can be useful regardless effects of storage environment, paper or printer. Furthermore, the application of this method in the analysis of counterfeit banknotes illustrated its feasibility and applicability. [ABSTRACT FROM AUTHOR]

Lanthanide neodymium (Nd)‐based nanocrystals exhibit exceptional near‐infrared II (NIR‐II) fluorescence imaging properties, like narrow and multi‐peak emissions, long luminescence lifetime, and good photostability. However, long‐term accumulation in the reticuloendothelial system restrains their clinical applications due to toxicity in vivo. Here, a biodegradable hollow virus‐like neodymium oxide (Nd2O3) Nd‐nanoprobe is presented that is modified with cyclic arginine‐glycine‐aspartic acid (cRGD) pentapeptide, showing remarkable cancer‐targeting ability and NIR‐II fluorescence imaging features. The nanoprobe is biodegraded to 4–6 nm Nd2O3 nanogranules in vivo, and the pharmacokinetics of the nanoprobe demonstrated its rapid urine excretion and negligible systematic toxicity. Moreover, this nanoprobe can accurately identify malignant lesions from normal tissues in xenograft and transgenic mice models and precisely navigate breast cancer surgery under NIR‐II imaging guidance. Taken together, this Nd2O3‐based nanoprobe enables real‐time, dynamic delineation and accurate resection of cancers guided by NIR‐II fluorescence imaging with great potential for future clinical translation during breast‐conservative surgery. [ABSTRACT FROM AUTHOR]

Phytohormone melatonin (MT) has shown promise in alleviating chilling injury (CI) in kiwifruit; however, the performance and mechanism remain largely unknown. In this study, the effect of pretreatment of MT at concentration of 0.05 mM on CI in 'Xuxiang' kiwifruit during storage at 1 °C for 90 d was investigated, as well as the implication of endogenous salicylic acid (SA) in MT-induced chilling-and oxidative-stress tolerance. MT pretreatment protected kiwifruit against CI, as figured out by lower CI index, firmness loss and soluble solids accumulation and better pulp appearance than those in control fruit. MT pretreatment stimulated endogenous SA generation by activating the gene expression of phenylalanine ammonia lyase (PAL) and activity of PAL and benzoic acid-2-hydroxylase, therefore up-regulated SA-responsive pathogenesis-related gene 1 expression, and provoked kiwifruit defense response to chilling stress. Moreover, reactive oxygen species in MT-pretreated fruit were neutralized by evaluating endogenous MT, ascorbic acid and glutathione contents and superoxide dismutase, catalase and ascorbate peroxidase activity, thus reducing membrane damage. However, such positive regulations of MT on kiwifruit were counteracted to varying extent by pretreatment of the combination of paclobutrazol PAC, a SA biosynthesis inhibitor, with MT. These findings indicated a mediating role of endogenous SA in chilling-and oxidative-stress tolerance in kiwifruit induced by MT pretreatment that could be operative by evoking defense response to chilling stress and enhancing antioxidative protection. • Exogenous MT pretreatment alleviated chilling injury in 'Xuxiang' kiwifruit. • MT elicited endogenous SA biosynthesis primarily through the PAL pathway. • MT-induced chilling-and oxidative-stress tolerance implicated the mediation of SA. [ABSTRACT FROM AUTHOR]

To investigate the correlation between electrochemical performance and physicochemical properties, three types of 1D WO3 nanostructures were fabricated by hydrothermal method using K2SO4, Na2SO4, and (NH4)2SO4 as capping agents. Hexagonal phase was obtained with the assistant of Na2SO4 and (NH4)2SO4, while monoclinic phase was developed using K2SO4 as agent. WO3 nanostructures prepared by (NH4)2SO4 and Na2SO4 exhibited superior specific capacitance (400 F/g and 388 F/g) relative to WO3 prepared by K2SO4 (259 F/g), suggesting hexagonal phase is more suitable for energy storage. The nanostructures prepared using Na2SO4 exhibited inferior rate performance compared with those obtained by (NH4)2SO4 due to low specific surface area and high crystallinity. The electrochemical performance demonstrated nanostructures prepared by (NH4)2SO4 was surface-controlled whereas those using Na2SO4 and K2SO4 were battery-type material. These findings raise the prospects of developing tungsten oxide for energy storage. [ABSTRACT FROM AUTHOR]

This study combined the structural characteristics of amanita peptide toxins to prepare a Fe 3 O 4 /P4VPBA/PPy/GO composite material as a magnetic solid-phase extraction adsorbent. The experimental results indicated that this adsorbent showed excellent selectivity for the extraction of amatoxins and phallotoxins from mushroom samples. Compared with traditional dispersive solid-phase extraction, this adsorbent enables rapid separation in the enrichment and elution recovery stages through the application of a magnetic field. Simultaneously, the study optimized the conditions for ultraperformance liquid chromatography–mass spectrometry (UPLC–MS/MS), ensuring both separation efficiency and accuracy while reducing the analysis time. The researchers established the MSPE–UPLC–MS/MS method for the determination of amanita peptide toxins in wild mushrooms. This method not only simplified and expedited the sample pretreatment process but also achieved qualitative and quantitative analyses in a short period, thus demonstrating high detection sensitivity and outstanding recovery rates. Furthermore, the developed method was successfully applied to analyze toxic mushrooms discovered in Nanjing, China. The potential for extensive utilization of this method is highlighted in the field of food analysis and detection. [Display omitted] • Magnetic nanocomposite Fe 3 O 4 /P4VPBA/PPy/GO was prepared and used as adsorbents. • MSPE-UPLC-MS/MS method for the analysis of amanita toxins. • The method was applied to the analysis of real poisonous mushroom samples. • The method has potential applications in food analysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • UPLC-Q-TOF MS fingerprint of G. elegans was established. • Fingerprint was conducted to analyze the differences before and after processing. • Compounds for significant changes were screened by PCA and OPLS-DA model. • Fifteen compounds were considered the tracing markers in poisoning cases. • The method can distinguish morphologically similar plants. Fingerprints of 13 batches of Gelsemium elegans (G. elegans) were established by ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF MS). The study aimed to explore the compositional variations in G. elegans before and after high-temperature processing and to distinguish it from honeysuckle and Ficus hirta Vahl. Chemical constituents of 25 peaks in G. elegans were identified by precisely determining retention times, MS2 spectra fragments, and validation against relevant databases and reference materials (RM). The entire analysis process was completed within 15 min. Moreover, the similarities and significant differences of chemical components of G. elegans before and after processing were analyzed via principal component analysis (PCA) and orthogonal partial least square discriminant analysis (OPLS-DA). The results showed that the contents of 10 components (kouminol, celastrol, sempervirine, 14,15-dihydroxygelsenicine, 4,20-dehydrogelsemicine, 4-O-caffeoylquinic acid, Nb-Methylgelsedilam, 3-hydroxykoumidine,14-acetoxygelsenicine, and humantenine) were related to the degree of processing. In addition, 15 alkaloids exhibited relative stability before and after processing, serving as distinctive marker compounds for traceability studies. This research provides a valuable basis for the source analysis and species traceability of toxin in forensic science. [ABSTRACT FROM AUTHOR]

A novel method, that the precursor is burnt in argon without further reduction to directly prepare metallic catalyst, is developed using low-valued by-product. Rice husk not only contributed as catalyst support, but also as reductant and fuel. The XRD, TPR and TG-DTA analysis prove that Cu phase in the as-burnt catalyst is almost reduced to metallic Cu 0 . The as-prepared catalysts exhibit higher activity and methanol selectivity than those prepared by a conventional impregnation method. This method may open a new way to prepare metallic catalysts without further reduction, especially for some catalytic reactions promoted by K, Ca, Mg and Mn. [ABSTRACT FROM AUTHOR]

Abstract: A series of the as-burnt and the burnt Cu/ZnO catalysts were prepared by a sol–gel auto-combustion method using metal nitrates with the mole ratio of Cu/Zn=1/1 (noted as M, M=Cu+Zn) and citric acid (noted as CA). When the xerogels were burnt in the argon atmosphere, H2 and CH4 which were came from the decomposition of the citric acid, were the reducing agents and were used in the redox process for synthesizing metallic Cu from Cu2+ in the chelated compound. The XRD patterns revealed that all the as-burnt catalysts with different M/CA molar ratios were converted into pure Cu and ZnO species. TPR analysis of the as-burnt catalyst illustrated that almost no hydrogen was consumed. It proved that Cu2+ in the chelated compound was absolutely reduced to metallic Cu in the as-burnt catalyst. The effects of M/CA molar ratio on the properties of catalysts were studied by TG-DTA, FT-IR, Raman spectrum, XRD, SEM-EDS, BET, and N2O chemisorption techniques. The activity of the as-burnt catalysts without reduction was investigated for low-temperature methanol synthesis from syngas containing CO2 using ethanol as a promoter at 443K and 5.0MPa for 12h. The total carbon conversion increased with increasing the content of citric acid and reached a maximum for the as-burnt Cu/ZnO catalyst C0.8 with M/CA=1/0.8, and then decreased. The variation trend was in accordance with that of the copper (Cu0) surface area. Comparing with the burnt catalyst C0.8-air after reduction, the methanol selectivity of the as-burnt Cu/ZnO catalyst was much lower owing to lower hydrogenation activity of the ethyl formate. The as-burnt catalyst C0.8 was also used in continuous low-temperature methanol synthesis at 443K and 5.0MPa for 40h. The total carbon conversion was stable after 15h and no obvious deactivation during 40h reaction, but the methanol selectivity was still not high. [Copyright &y& Elsevier]

Abstract: A multi-functional bimodal pore catalyst support, alumina–silica bimodal pore support, was prepared from a polymer complex solution and silica gel. The obtained bimodal pore support had two kinds of main pores; the pore volume was decreased and the specific surface area was enlarged, comparing with the original silica gel. This kind of bimodal pore support was applied in slurry phase Fischer-Tropsch synthesis, where cobalt was supported as active metal. Alumina–silica bimodal pore catalyst exhibited high catalytic activity and favorite selectivity, due to the spatial effects of bimodal pore structure and chemical effects of coexisting alumina, which formed the new small pores inside SiO2 large pores. Alumina–silica bimodal pore catalyst showed higher activity than silica–silica bimodal pore catalyst with similar pore structure, proving that hetero-atom bond between alumina and silica was important to promote the performance of the dispersed cobalt. The various catalysts were characterized by XRD, chemisorption, in situ DRIFT, TPR, and TPSR. It was found that alumina in alumina–silica bimodal structure improved cobalt dispersion significantly while keeping the reduction degree almost the same. TOF of alumina–silica bimodal catalysts was the highest, supported by the largest bridge-type adsorbed CO peak in DRIFT observation of this catalyst, as bridge-type adsorbed CO was the active intermediate in FTS. [Copyright &y& Elsevier]

[Display omitted] • SERS detection of morphine can be realized by dropping or soaking with a solid chip. • This chip is fit for detecting morphine in aqueous solutions even domestic sewage. • Suitable modification of the chip can increase its SERS performances to morphine. The accurate, sensitive and portable detection of morphine is important to handle judicial cases, but remains to be a great challenge. In this work, a flexible route is presented for the accurate identification and efficient detection of trace morphine in solutions based on surface-enhanced Raman spectroscopy (SERS) and a solid substrate/chip. A gold-coated jagged silicon nanoarray (Au-JSiNA) is designed and prepared via Si-based polystyrene colloidal template-reactive ion etching and sputtering deposition of Au. Such Au-JSiNA has three-dimensional nanostructure with good structural uniformity, high SERS activity and hydrophobic surface. Adopting this Au-JSiNA as SERS chip, trace morphine in solutions could be detected and identified in both dropping and soaking ways, and the limit of detection is below 10-4 mg/mL. Importantly, such chip is especially suitable for the detection of trace morphine in aqueous solutions and even domestic sewage. The good SERS performance is attributed to the high-density nanotips and nanogaps on this chip as well as its hydrophobic surface. Additionally, the appropriate surface modification of this Au-JSiNA chip with 3-mercapto-1-propanol or 3-mercaptopropionic acid/1-(3-dimethylaminopropyl)-3-ethylcarbodiimide can further increase its SERS performances to morphine. This work provides a facile route and practical solid chip for SERS detection of trace morphine in solutions, which is significant to develop the portable and reliable instruments for on-site analysis of drugs in solutions. [ABSTRACT FROM AUTHOR]

Ethanol use mainly as an alternative green fuel has attracted global attention, hence need for the development of more improved synthesis pathways. In this work, we proposed an in situ direct ethanol synthesis pathway, where dimethyl ether (DME) was co-fed with syngas (CO + H2) over a combination of metal impregnated zeolite (Cu-MOR) and ternary oxide CuO/ZnO/Al2O3 (CZA) catalysts, disjointly packed in a dual bed reactor. The route first transformed DME into an intermediate ester (methyl acetate) by carbonylation reaction on the upper modified zeolite catalyst, followed by hydrogenation of the intermediate ester into ethanol on the lower CZA catalyst. Dimethyl ether conversion reached 75.72% with an ethanol selectivity of 48.05% under Cu loading amount of 13 wt% of zeolite support. [ABSTRACT FROM AUTHOR]

The nickel particle size, distribution and interaction with support are crucial to the catalytic performance in dry reforming of methane reaction (DRM). Despite numerous literatures on dry reforming catalysis, the effect of solution pH on the catalytic performance is not well studied. Herein, we designed a series of Ni/SiO2 catalysts with different Ni particle sizes. The Ni particle size was controlled with altering the pH of the Ni nitrate solution via the addition of HNO3 or NH4OH. X‐ray diffraction (XRD) revealed that NH4OH promoted Ni/SiO2 catalysts present smaller NiO nanoparticles, and enhanced metal‐support interaction was evidenced from X‐ray photoelectron spectra (XPS) and H2 temperature‐programmed reduction (H2‐TPR) analyses. In addition, according to thermogravimetric analysis and differential scanning calorimetry (TG‐DSC) and transmission electron microscopy (TEM) results, the spent catalysts produced less carbon deposition and maintained Ni nanoparticles in smaller size after DRM reaction. Catalysts with nearly uniform and small particle size demonstrated a satisfying resistance to aggregation and carbon deposition, while realizing a high CH4, CO2 and Ctotal conversion (74.5, 83.7 and 79.7%, respectively). The present study provides a simple but effective way to change the metal‐support interaction and metal particle size. [ABSTRACT FROM AUTHOR]

Highlights • Hierarchical feather duster-like CNT@WO 3 composite is prepared by solvothermal method. • The WO 3 nanosheet arrays grow vertically on the CNT surface. • The composite shows high specific capacitance and good cycling stability. Abstract In order to develop active material with promising properties for supercapacitor, the feather duster-like CNT@WO 3 composite is synthesized by a facial on-step solvothermal method. The as-prepared material shows the superior electrochemical properties with high specific capacitance (496 F g−1 at 0.5 A g−1) and long-lasting cycle stability (96.3% retention after 8000 cycles at 100 mV s−1) in 0.5 mol L−1 H 2 SO 4 electrolyte. This simple preparation method and superior performance can make significant contribution in the synthesis and future application in energy storage material. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Silicalite-1 based microcapsule catalysts were prepared with hydrothermal synthesis. • Silicalite-1 shell turned Fe/ZSM-5 core's surface hydrophilicity to hydrophobicity. • Hydrophobic nature of silicalie-1 layer decreased water-gas shift reaction's kinetics. • CO 2 selectivity was decreased by suppressing water-gas shift reaction activity. • Acidic ZSM-5 and silicalite-1 molecular sieving contributed in high gasoline selectivity. Abstract Zeolite supported Fischer-Tropsch (FT) catalysis has attracted extensive attentions in past few years. Capsule catalysts have unique characteristics of tuning product selectivity more precisely and enhancing stability of catalysts during reaction, which makes them to stand out of the crowed. Fe-based FT catalysts have been facing limitations for syngas conversion to hydrocarbons with their associated problems of high CO 2 selectivity and rapid catalyst deactivation. A series of ZSM-5 supported Fe-based microcapsule catalysts, composed of Fe/ZSM-5 core and silicalite-1 shell, was prepared and employed for direct synthesis of gasoline range hydrocarbons from syngas. Tuning silicalite-1 shell thickness significantly affected water-gas shift reaction with increasing hydrophobicity of catalyst surface, and greatly decreased CO 2 selectivity. The microcapsule catalysts significantly suppressed the CO 2 selectivity as compared with supported Fe-based catalyst. Moreover, all zeolite supported Fe-based catalysts, showed significantly high gasoline range hydrocarbons selectivity (about 60%). The proposed catalyst design suggests a promising approach to overcome high CO 2 selectivity challenge associated with Fe-based FT catalysts. [ABSTRACT FROM AUTHOR]

Methanol is an essential chemical raw material and potential alternative energy source. In this paper, Cu based catalyst was prepared by the noble solid phase grinding method for CO2 hydrogenation to methanol. The influence of chelating agent, heating rate, calcination temperature and calcination period of the precursor on catalyst performance were studied in depth. The catalyst precursor with formic acid as a chelating agent was reduced in‐situ when calcined in nitrogen (N2) at 573 K. The formic acid was decomposed, releasing the reducing agents, CO and H2, resulting in continuous in‐situ CuO reduction to metallic Cu0. XRD, XPS, BET, TG‐DSC, H2‐TPR and other characterization techniques were employed to analyze the catalyst properties. Results revealed that CuO was successfully reduced in‐situ to Cu0 during calcination process in a nitrogen atmosphere without further reduction. The catalyst prepared by formic acid grinding (F/I−Cu/ZnO) showed highest catalytic activity compared with the conventional catalyst which was further reduced by 5% H2 (F/H−Cu/ZnO). CO2 conversion and methanol selectivity reached 33.44% and 84.26%respectively. [ABSTRACT FROM AUTHOR]

Abstract The traditional methods for zeolite synthesis include use of various solvents that tend to produce pollutants. It is therefore necessary to find green and efficient routes for zeolite synthesis. Herein, we demonstrated a detailed way to synthesize MOR zeolite by a solvent-free method. The synthesized MOR zeolite was characterized by XRD, SEM, TEM, N 2 sorption, MAS NMR and UV-Raman spectroscopy. Compared with other routes, solvent-free method not only addresses pollution issues, but also significantly enhances the yield. A 650 g mass of MOR zeolite with good crystallinity was obtained in 1 L Teflon by one-time synthesis. The optimum conditions for fast synthesis of large amounts of high purity MOR zeolite crystals are the SiO 2 /Al 2 O 3 /Na 2 O = (7.5–25)/1/1, crystallization temperature and period at 200 °C for 24 h. Graphical abstract Image 1 Highlights • MOR zeolite is prepared by solvent-free grinding method. • Optimum synthesis conditions of MOR zeolite via the solvent-free route are examined in detail. • Significantly high product yield is obtained by solvent-free synthesis. • Mass production of high crystallization MOR zeolite can be achieved in laboratory. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Microwave-assisted hydrothermal carbonization of rice straw. • Relation between microwave conditions and hydrochars' physical-chemical properties. • Adsorption of three organics and two heavy metals on the hydrochars. Abstract A series of rice straw hydrochars were produced through a microwave-assisted hydrothermal treatment method, characterized and used for the adsorption of three organics and two heavy metals from aqueous solutions. The hydrochars have carbon contents from 37.44% to 43.31%, are rich in oxygen containing functional groups, and the equilibrium of hydrothermal carbonization reactions could be reached rapidly in microwave environment. The hydrochars can effectively adsorb the model pollutants, the maximum adsorption capacities of Congo red, berberine hydrochloride and 2-naphthol at 298 K and initial concentration of 0.5 mg/mL were 222.1, 174.0 and 48.7 mg/g, respectively, and those of Zn2+ and Cu2+ were 112.8 and 144.9 mg/g, respectively. Adsorption thermodynamic parameters were calculated. These results suggest that microwave-assisted hydrothermal treatment is an effective method for the rapid production of hydrochars, and rice straw hydrochars are promising adsorbents for the removal of water pollutants such as organics and heavy metals. [ABSTRACT FROM AUTHOR]

Zeolite synthesis involved use of large volumes of solvent that resulted in waste and enhanced production costs. In our study, we selected a solvent‐free synthesis route that involved mixing, grinding and crystallization at various times creating Fe@Silicalite‐1. This synthesis method produced a hierarchical in‐situ microporous crystal morphology with Fe particles caged inside zeolite displaying a high gasoline (C5‐C11) selectivity of 66.0% with a relatively low CO2 and CH4 selectivity (18.5% and 10.0%, respectively) in Fischer‐Tropsch synthesis. Prolonged crystallization time of 72 h and other subsequent procedures contributed to zeolite structure and performance. Iron moieties were appropriately immobilized over silicalite support. The characterization results were correlated with the zeolite activity and selectivity. This novel zeolite at its best possesses all the potential to be advanced in other related material synthesis because of its expedient procedure, characteristics and worthwhile outcomes. As a result of solvent‐free synthesis route, this Fe@Silicalite‐1 zeolite containing hierarchical in‐situ microporous crystal structure in union with Fe particles entrapped within zeolite contributed largely to gasoline product distribution of Fischer‐Tropsch synthesis reaction. The remarkable high gasoline selectivity of 66.0% has been achieved by this zeolite as a result of its intrinsic properties. [ABSTRACT FROM AUTHOR]

A series of bamboo hydrochars were prepared through acid-assisted and two-stage hydrothermal carbonization, characterized and evaluated for the adsorption of Congo red and 2-naphthol in aqueous solutions. The hydrochars have rough surfaces with BET surface areas of 6.77–57.74 m 2 /g and oxygen-rich functional groups. The additives in feed water revealed critical influences on the physical-chemical and adsorption properties of the hydrochars. The hydrochars can adsorb the two organics effectively, the highest adsorption capacities for Congo red and 2-naphthol are 90.51 and 72.93 mg/g, respectively, at 0.1 mg/mL and 298 K. The adsorption of the two organics on the selected hydrochars is a spontaneous and mainly physical adsorption process. 95% and 92% of the adsorption equilibrium could be accomplished in one hour for Congo red and 2-naphthol on the selected hydrochars, respectively. This study provides references for the production and application of hydrochars as efficient adsorbents in wastewater treatment. [ABSTRACT FROM AUTHOR]

• A rapid and sensitive QuEChERS-UPLC-Q Exactive orbitrap HRMS method was established for determining ten neonicotinoid insecticides and a metabolite in human whole blood. • The QuEChERS method was optimized in detail for the type and dosage of extraction solvent, salting-out agent, and adsorbent. • First to choose human whole blood as the study matrix for neonicotinoid insecticides. • The method was successfully applied to a real case of neonicotinoid insecticide poisoning. Since neonicotinoid insecticides are now the most extensively used insecticides worldwide, there are increasing cases of neonicotinoid poisoning. A rapid and sensitive method was developed for the determination of ten neonicotinoid insecticides and a metabolite 6-chloronicotinic acid in human whole blood. The types and amounts of extraction solvent, salting-out agent, and adsorbent in the QuEChERS method were optimized by comparing the absolute recoveries of 11 analytes. The separation was performed on an Agilent EC18 column with the gradient elution with 0.1% formic acid in water and acetonitrile as the mobile phase. The quantification was achieved by Q Exactive orbitrap high-resolution mass spectrometry under parallel reaction monitoring scan mode. The 11 analytes showed good linearity with R2 ≥ 0.9950, LODs ranging from 0.01 μg/L to 0.30 μg/L, and LOQs from 0.05 μg/L to 1.00 μg/L. The recoveries ranged from 78.3% to 119.9% at low, medium, and high spiked concentrations of blank blood, with matrix effects ranging from 80.9% to 117.8%, inter-day RSDs from 0.7% to 6.7%, and intra-day RSDs from 2.7% to 9.8%. The method was furthermore applied to a real case of neonicotinoid insecticide poisoning to demonstrate its feasibility. The proposed method is suitable for the rapid screening of neonicotinoid insecticides in poisoned human blood in the field of forensic science, as well as monitoring of neonicotinoid insecticide residues in humans in the field of environmental safety, compensating for a lack of studies on neonicotinoid insecticide determination in biological samples. [ABSTRACT FROM AUTHOR]

Liquefied petroleum gas (LPG, C3 and C4 paraffins) from syngas have attracted much attention recently due to the growing demand of non-oil resource as well as its environmentally friendly features, but the catalytic reaction process controlled by thermodynamics and CO conversion rate is low with many side reactions. Here we report a catalyst with core shell structure for LPG synthesis from syngas. Zeolite as shell was synthesized by hydrothermal method firstly and then coated on Cu/ZnO core with Ludox (CZ@Z), the Cu/ZnO core was prepared by co-precipitation method. The unique core shell structure had efficient synergistic effect. The reaction equilibrium favored forward reaction because methanol as an intermediate was directly transformed to dimethyl ether. The zeolite type in the core shell structure catalyst had great effects on the activity and selectivity. The catalysts have been characterized by XRD, NH 3 -TPD and SEM. The activities were determined after in situ H 2 reduction. CZ@H-β catalyst showed a more effective catalytic activity compared with the traditional hybrid catalyst. The excellent catalytic performance was attributed to the combined contribution of both unique core shell structure and proper zeolite type. At these reaction conditions, temperature of 350 °C, pressure of 3.0 MPa and flow rate of 40 ml min −1 , CO conversion and hydrocarbons selectivity achieved 61.8% and 64.2%, respectively. LPG selectivity in hydrocarbons was 70.2%. [ABSTRACT FROM AUTHOR]

A facile synthesis route, named dual-layer crystal growth method, was developed for preparing Pd-based zeolite capsule catalyst. The millimeter-sized zeolite capsule catalyst (Pd/SiO 2 -SZ) with a core-shell structure was prepared by a developed dual-layer crystal growth method: coating Silicalite-1 and H-ZSM-5 zeolite orderly as double shells encapsulating the Pd/SiO 2 core catalyst. We employed the prepared Pd/SiO 2 -SZ zeolite capsule catalyst for the direct synthesis of liquefied petroleum gas (LPG) from syngas (CO + H 2 ). In the reaction, the zeolite capsule catalyst showed excellent LPG selectivity than the single core catalyst of Pd/SiO 2 and the physical mixture catalyst prepared by a simply mixing core and shell catalysts. The Pd/SiO 2 -SZ realized the highest LPG selectivity of 34.4% with CO conversion of 14.1%. Moreover, the optimal reaction temperature and pressure in the reaction for LPG direct synthesis from syngas over Pd/SiO 2 -SZ catalyst were 623 K and 5.0 MPa, respectively. The high performance of zeolite capsule catalyst Pd/SiO 2 -SZ was attributed to the enforced mass transfer diffusion from inside to outside of the catalyst. [ABSTRACT FROM AUTHOR]

Zeolite-based capsule catalysts have exhibited significant results in terms of catalytic activity and product selectivity in Fisher-Tropsch synthesis. Herein, we synthesized a ZSM-5 supported Co based microcapsule catalyst encapsulated by microporous silicalite-1 shell via hydrothermal synthesis process. Synthesized microcapsule catalyst has a uniform microporous structure with an additional stay zone for both reactants as well as product inside its channels and showed significantly high CO conversion rate (68.9%) and gasoline range hydrocarbon selectivity (74.7%) with a low CO 2 and CH 4 selectivity (2.8% and 8.7%, respectively). This microcapsule catalyst may consider to be used on commercial scale because of its facile preparation method and promising performance. [ABSTRACT FROM AUTHOR]

Mesoporous Ni-Mg-Al and Ni-Al catalysts were facilely synthesized via evaporation-induced self-assembly (EISA) method and employed for coupled reforming reaction consisting of dry reforming of methane (DRM) and partial oxidation of methane (POM) to produce syngas (H 2 + CO). The Ni-Mg-Al and Ni-Al catalysts with encapsulated nickel nanoparticles were directly synthesized in one-pot way. For comparison, Ni/Al 2 O 3 as reference catalyst was also prepared by general impregnation method. Characterization by BET, XRD and H 2 -chemisorption revealed that the Ni-Mg-Al catalyst owned larger surface area and higher Ni dispersion as well as smaller metallic Ni particles size compared to Ni-Al and Ni/Al 2 O 3 catalysts. CO 2 -TPD demonstrated that the Ni-Mg-Al catalyst presented stronger basicity due to Mg incorporation. H 2 -TPR confirmed that the reduction of Ni-based species to Ni 0 was performed in high temperature due to the formed NiAl 2 O 4 phase. Activity tests indicated that this Ni-Mg-Al catalyst, due to its excellent physicochemical property, exhibited higher CH 4 conversion, H 2 selectivity, and H 2 /CO ratio in the coupled DRM-POM reaction. XRD, SEM and TG-DTA analyses of the used catalysts disclosed that the Mg-modified Ni-Mg-Al catalyst for syngas production using coupled DRM-POM reaction exhibited robust resistance to coke deposition. Consequently, by the synergistic cooperation between the coupled DRM-POM reaction and Mg-modified Ni-Mg-Al catalyst, high catalytic activity and stability could be accomplished to produce syngas. [ABSTRACT FROM AUTHOR]

It is challenging to fabricate a multifunctional catalyst for consecutively catalyzing multiple reactions. Herein, we report a well-defined metal-zeolite interface derived from a CuZnAl@H-Beta core@shell catalyst to realize one-step syngas conversion to liquefied petroleum gas (LPG). The multifunctional interface between CuZnAl core and H-Beta zeolite shell is composed of Cu and acid zeolite with a content gradient, through which synthesized methanol via syngas on the core will pass. The interface is able to catalyze the tandem dehydration of methanol to olefins on acid sites and olefin hydrogenation to C 3–4 saturated hydrocarbons (LPG fraction) over exposed Cu sites on the interface instead of noble metals in conventional catalysts. The selectivity of LPG in hydrocarbons over the prepared capsule catalyst reaches as high as 77% accompanied by a record low methane and C 2 selectivity (<2.0%). [ABSTRACT FROM AUTHOR]

Designing catalyst with the combined merits of heterogeneous catalysts and homogeneous catalysts through much simple one-step preparation process is always a challenge in catalysis. In this report, organic ligand triphenylphosphine (PPh 3 ) is first introduced as a reducing agent to reduce graphene oxide (GO) and accomplish a reduced graphene oxide (rGO) supported metal-ligand complex catalyst simultaneously. Here, the employed PPh 3 not only acts as an effective reducing agent to reduce GO, but also as a functional group to in-situ form ligand functionalized rhodium catalyst immobilized on rGO (PPh 3 -Rh/rGO). The prepared PPh 3 -Rh/rGO catalyst, as a heterogeneous catalyst, is applied in 1-olefins hydroformylation to form normal aldehyde, exhibiting remarkable catalytic activity and selectivity compared with other heterogeneous catalysts. It affords aldehydes in higher yields with better regioselectivity on linear products than those of other two reference catalysts reduced by ethylene glycol and hydrazine hydrate. More importantly, this efficient and simple method for preparing ligand modified metal complex catalyst supported on rGO is scalable. The great varieties of organic ligands can be chosen to extend the synthetic strategy for preparing rGO supported metal-ligand complex catalysts for various reactions. [ABSTRACT FROM AUTHOR]

The Cu/ZnO catalyst prepared by urea hydrolysis method was investigated for low-temperature methanol synthesis from syngas containing CO 2 . Concurrently, the activity of the conventional Cu/ZnO catalyst prepared by co-precipitation method was also compared. The effects of precipitation temperature, urea content, stirring speed and the introduction of Al on the catalytic performance of Cu/ZnO were deeply studied. It was found that the total carbon conversion of the Cu/ZnO catalyst prepared by urea hydrolysis method was increased to 45.0% from 32.8%, comparing with that of the catalyst prepared by co-precipitation method. The structure, BET surface area, surface morphology of the catalyst were characterized by XRD, BET, EDX and SEM. The catalyst prepared by urea method obtained higher BET surface area and larger metallic surface area of Cu than those of the co-precipitation method. The crystals sizes of Cu by urea method were smaller than those of co-precipitation method. Surface structure prepared by urea method had needle shape, and it could increase the surface area, different from the catalyst by co-precipitation method. Both the increased BET surface area of the catalysts and the enhanced metallic surface area of Cu 0 promoted the catalyst activity for the low-temperature methanol synthesis. The deactivation of the Cu-ZnO catalysts prepared by urea method was not observed in low-temperature methanol synthesis here. [ABSTRACT FROM AUTHOR]

Selectivity control of target product(s) is an enormous challenging in cascade catalytic or tandem system. We demonstrated a facile and fast route to directly construct zeolite-based micro-capsule catalyst with mesoporous nano-silica shell. The as-prepared out-Co/HY@SiO 2 catalyst has achieved an excellent performance of CH 4 and C 5–11 selectivity with 16.4 and 65.0% respectively, as well as low CO 2 selectivity of 2.1%. As expected, the mesoporous shell of micro-capsule catalyst could offer the spatial confinement effects, especial the stay zone of intermedium products for long chain hydrocarbons formation, which were hydrocracked by acidic HY core, consequently tuning the products selectivity. [ABSTRACT FROM AUTHOR]

A silicon carbide (SiC) foam monolith decorated with a carbon nanofibers (CNFs) layer was employed as the catalyst support for Ni-based catalyst preparation, used for the CO 2 dry reforming of methane (DRM) reaction. The loading amount of CNFs on the SiC foam monolith was 6.6 wt.%, which obviously increased the surface area of the pristine SiC foam from 4 m 2 /g to 24 m 2 /g. The prepared CNFs layer strongly attached to the pristine SiC surface and was considerably stable even after 100 h time on stream (TOS) DRM reaction. The CNFs decorated SiC composite support provided more anchorage sites for improving the dispersion of the Ni particles and enhanced the metal-support interaction compared to the pristine SiC support. Compared with other catalysts such as Ni/SiC and Ni/CNFs, the Ni/CNFs-SiC catalyst exhibited not only the highest activity but also remarkable stability during DRM reaction. The XPS and SEM-EDS results showed that the carbon deposition over the nickel surface of Ni/CNFs-SiC catalyst was much less than those of Ni/SiC and Ni/CNFs catalysts. In addition, the XRD analysis verified that almost no sintering of nickel particle was detected over the Ni/CNFs-SiC catalyst, which was prepared with CNFs-SiC composite as catalyst support, even after 100 h TOS DRM reaction at 750 °C. [ABSTRACT FROM AUTHOR]

Heteroatom doping is a promising approach to improve the properties of carbon materials for customized applications. Herein, a series of Cu catalysts supported on boron-doped carbon nanotubes (Cu/ xB-CNTs) were prepared for the hydrogenation of dimethyl oxalate (DMO) to ethanol. The structure and chemical properties of boron-doped catalysts were characterized by XRD, TEM, N2O pulse adsorption, CO chemisorption, H2 temperature-programmed reduction, and NH3 temperature-programmed desorption, which revealed that doping boron into CNT supports improved the Cu dispersion, strengthened the interaction of Cu species with the CNT support, introduced more surface acid sites, and increased the surface area of Cu0 and especially Cu+ sites. Consequently, the catalytic activity and stability of the catalysts were greatly enhanced by boron doping. 100 % DMO conversion and 78.1 % ethanol selectivity could be achieved over the Cu/1B-CNTs catalyst, the ethanol selectivity of which was almost 1.7 times higher than that of the catalyst without boron doping. These results suggest that doping CNTs with boron is an efficient approach to improve the catalytic performance of CNT-based catalysts for hydrogenation of DMO. The boron-doped CNT-based catalyst with improved ethanol selectivity and catalytic stability will be helpful in the development of efficient Cu catalysts supported on non-silica materials for selective hydrogenation of DMO to ethanol. [ABSTRACT FROM AUTHOR]

A series of Ni/C–SiO 2 catalysts with high Ni 0 dispersion were prepared through impregnation method with glucose as the carbon source as well as the reduction agent. During the calcination process under N 2 atmosphere, the generated reductive substances, like CO, H 2 and carbon derived from decomposition and carbonization of glucose, which could transform NiO into Ni 0 particles completely, according to XRD and H 2 -TPR analysis. To improve the catalytic performance of CH 4 –CO 2 reforming reaction, the Ni/C–SiO 2 catalyst was further pretreated under N 2 , H 2 and CO 2 atmosphere prior to the reaction. The CO 2 pretreated catalyst exhibited excellent catalytic activity and superior stability comparing with other catalysts. A rapid deactivation occurred on the Ni/SiO 2 catalyst prepared by traditional impregnation method during 10 h test. Reversely, the CO 2 pretreated catalyst maintained a high CH 4 , CO 2 and C total conversion (71.1, 81.1 and 77.1%, respectively) during a 40 h time-on-stream test, which was attributed to homogenous Ni particles dispersion and strong interaction between metal and support. This methodology opens up a possibility for diversification in carbon-silica composite catalysts. The working catalyst without further reduction process will give the required metal-support interaction for the novel synthesis. [ABSTRACT FROM AUTHOR]

A hierarchically spherical Co based zeolite catalyst with aggregated nanorods structure (simplified as Co/AN-Z) was prepared by an in-situ self-assembly crystallization route of Co/SBA-15 under hydrothermal synthesis environment. The obtained Co/AN-Z catalyst with uniformly sized zeolite microspheres with 0.5–1 μm was evaluated for improved Fischer–Tropsch synthesis (FTS) reaction activity and isoparaffin selectivity. The selectivities of isoparaffin and C 5-11 hydrocarbons were higher with a narrower product distribution as well as CH 4 and C 12+ selectivities were lower on the Co/AN-Z catalyst than those on the commercial HZSM-5 supported Co catalyst (Co/HZSM-5) for FTS reaction. The demonstrated route of the hierarchically spherical Co based zeolite catalyst can be extended to synthesize bifunctional catalyst and expected to find a new approach for tandem reaction. [ABSTRACT FROM AUTHOR]

High quantum yield quantum dots (QDs) with the emission in the sub-second near infrared window (NIR-IIb, 1500–1700 nm) can afford higher resolution, a deeper penetration depth and zero auto-fluorescence for bio-imaging. However, low tumor accumulation, the rapid renal clearance and potential toxicity impeding their biomedical applications. Here, we report a tumor microenvironment responsive hollowed virus-bionic MnO 2 nanoshell with IR1061 loading in the cavity and QDs (PbS@CdS) anchoring on the surface for precise NIR-IIb fluorescence imaging guided tumor surgery and efficient NIR-II photothermal therapy. This QDs based nanoprobe could efficiently adhere on tumor cells to realize efficient tumor tissue accumulation. NIR-IIb fluorescence of tumor margin could be successfully delineating after extracellular weak acid triggered MnO 2 biodegradation for IR1061 release with remarkable NIR-IIb signal-to-noise boosting. Then, it could facilitate complete dissection of various tumor models with the assistance of NIR-IIb fluorescence imaging. Moreover, the fascinating efficacy for micro-metastasis eradication via NIR-II photothermal effects can be achieved under NIR-IIb fluorescence imaging guidance. Specifically, in combination with negligible system toxicity, our nanoprobes showed great potential as a versatile NIR-IIb fluorescent imaging platform for precise tumor surgery and tumor therapy guidance for future clinical translation. [ABSTRACT FROM AUTHOR]

A facile synthesis route for directly preparing Ni-based mesoporous carbon/silica composite catalysts without further reduction was synthesized successfully. The synthesis procedure was achieved by using the one-step solid–liquid grinding method with a mixture of SiO 2 , soybean oil, and nickel acetyl acetonate. Calcination was then performed with different temperatures to obtain the Ni-based mesoporous carbon/silica composite catalyst. All experimental steps were conducted without solvent addition. In this catalyst structure, soybean was used as the carbon source and provided a large surface area within the silica skeleton; Ni 0 was used as the active metal. The active component Ni 0 was formed directly during the soybean oil carbonization process. A series of Ni/SiO 2 –C–X catalysts (X = 400–1100, X stands for the carbonization temperature) were applied for the CO 2 reforming of CH 4 reaction. The unreduced Ni-based catalyst showed a better catalytic activity than that of the reduced catalyst under hydrogen atmosphere because the NiO phase was in-situ reduced by the carbonized soybean under nitrogen. The Ni/SiO 2 –C–500 catalyst showed stable activity and high reaction activity in the continuous CO 2 reforming reaction of CH 4 at atmospheric pressure. [ABSTRACT FROM AUTHOR]

The Cu/ZnO catalyst prepared by supercritical phase CO 2 drying (denoted as CZS catalyst) and the conventional Cu/ZnO catalyst prepared by heating dry process (denoted as CZO catalyst) were comparatively investigated. The low-temperature methanol synthesis reaction from CO + CO 2 + H 2 using 2-butanol as solvent was conducted over the CZS and CZO catalysts at 443 K and 5.0 MPa for continuous 20 h in a flow-type reactor. It was found that the total carbon conversion of the CZS catalyst was increased from 35.1% to 46.4% and the methanol yield of the CZS catalyst was enhanced from 33.8% to 44.8%, comparing with those of the CZO catalyst. The results of kinetic analysis by in situ diffuse reflectance infrared Fourier transform spectra (DRIFTS) revealed that the reaction rate of the low-temperature methanol synthesis on CZS catalyst was faster than that on CZO catalyst at 443 K, in good accordance to the catalytic reaction performances. It was indicated that the supercritical fluid CO 2 , which was used to dry the catalyst precursor, suppressed the sintering of the Cu and ZnO particles and increased both the BET surface area of the catalysts and metallic surface area of Cu 0 , which further improved the reaction activity of the catalyst for the low temperature methanol synthesis. [ABSTRACT FROM AUTHOR]

Twelve hydrochars were produced from bamboo sawdust for adsorption of Congo red and 2-naphthol. The bamboo hydrochars have Brunauer–Emmett–Teller (BET) surface areas ranging from 2.63 m 2 /g to 43.07 m 2 /g, average pore diameters from 3.05 nm to 3.83 nm, pore volumes between 0.02 cm 3 /g and 0.53 cm 3 /g, and the surfaces of the hydrochars have diverse functional groups. The physico-chemical properties of the hydrochars critically depend on the hydrothermal conditions. All the hydrochars can adsorb Congo red and 2-naphthol from aqueous solutions, the largest adsorption capacity for Congo red is 33.7 mg/g at the equilibrium concentration of 0.1 mg/mL at 25 °C, and the highest adsorption amount for 2-naphthol is 12.2 mg/g at 25 °C and 0.1 mg/mL. Freundlich model can describe the adsorption isotherms of the both adsorbates slightly better than Langmuir model. These results provide a reference to the production and use of hydrochars as potential adsorbents in wastewater treatment. [ABSTRACT FROM AUTHOR]

A novel iron-based micro-capsule catalyst with interior Fe/Silica core and exterior H-ZSM-5 shell was synthesized via in-situ crystallization route on Fe/SBA-15 catalyst by using steam-assisted crystallization (SAC) process and evaluated for direct synthesis of middle isoparaffin from syngas in a fixed-bed reactor. Structure characterization indicated that the size of micro-capsule catalyst was about 1–2 μm. According to activity test results, original Fe/SBA-15 catalyst exhibited a low selectivity of isoparaffin as 8.2%. But the as-prepared micro-capsule catalyst achieved an excellent performance for isoparaffin synthesis with the selectivity up to 46.5%. Meanwhile, the physical mixture catalyst (Fe/SBA-15 and H-ZSM-5) exhibited lower isoparaffin selectivity with 33.9% than that of the micro-capsule catalyst. The spatial confinement effect of the micro-capsule catalyst played an important role for the high selectivity of isoparaffin synthesis. [ABSTRACT FROM AUTHOR]

Hierarchical HZSM-5 zeolite with combined micropores and mesopores was synthesized by one-step approach with TPAOH and F127 as dual templates. The physical and acidic properties of the hierarchical HZSM-5 zeolite were characterized by XRD, N 2 adsorption–desorption isotherm, SEM, TEM, and NH 3 -TPD techniques. The hierarchical HZSM-5 zeolite exhibited a significantly higher mesopore surface area and larger mesopore volume than that of the conventional HZSM-5. The prepared hierarchical HZSM-5 and conventional HZSM-5 zeolite supported cobalt catalysts were evaluated via Fischer–Tropsch synthesis (FTS) reaction to tune product selectivity. Compared with the conventional catalyst, the CO conversion of FTS reaction on the present catalyst increased significantly. Meanwhile, the C 5 + selectivity and isoparaffin selectivity also increased. The C 5–11 hydrocarbons with a lot of isoparaffin and olefin had become the main FTS products due to the optimized hydrocracking and isomerization afforded by the hierarchical pore structure, different from the conventional FTS hydrocarbons which were mainly composed of normal paraffin. [ABSTRACT FROM AUTHOR]