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Background Epidermal growth factor-like domain 7 (Egfl7), a recently identified secreted protein, was significantly increased in patients with HCC by our previous studies. However, its efficacy in the diagnosis of early HCC remains unknown. In this study, we therefore evaluate the efficacy of serum Egfl7 for early HCC diagnosis and compare it with alpha-fetoprotein (AFP). Methods Serum Egfl7 levels in testing cohort (1081 participants) and validation cohort (476 participants) were measured by a sandwich enzyme-linked immunoassay (ELISA). The cut-off value of Egfl7 was determined by Youden’s index and the efficacies of Egfl7 and AFP in diagnosing early HCC were estimated by receiver operating characteristic (ROC). Results Serum Egfl7 was significantly elevated in patients with early HCC than all non-HCC controls in whatever Testing Cohort or Validation Cohort. In the Testing Cohort, ROC curves showed the optimum cut-off value of Egfl7 was 2610 ng/mL and Egfl7 showed a significantly higher sensitivity than AFP in discriminating early HCC from healthy individuals (77.4% vs. 65.3%, P = 0.0013) but the area under ROC (AUROC) and accuracy of Egfl7 and AFP were similar (0.860 vs. 0.868, P = 0.704; 80.2% vs. 83.8%, P = 0.184). In distinguishing patients with early HCC from patients with chronic liver disease (CLD), the AUROC, sensitivity, specificity and accuracy of Egfl7 were 0.800, 75.2, 71.7 and 73.5%, which were all significantly higher than AFP (0.675, 61.8, 62.0 and 61.9% in order). Egfl7 also showed a significant higher sensitivity and accuracy than AFP (76.6% vs. 64.0%, P = 0.0031; 79.9% vs. 66.1%, P Conclusion Egfl7 is a valuable serum marker in the diagnosis of early HCC and could complement the efficacy of AFP, especially in distinguishing early HCC from CLD and identifying patients with AFP-negative early HCC.

N-Heterocyclic carbene (NHC), generated in situ from easily available N-heterocyclic imidazolium salt with air as terminal oxidant, has successfully been utilized as a cheap and efficient catalyst for one-pot aerobic oxidative synthesis of 2-arylbenzo[d]oxazoles, 2-substituted benzo[d]thiazoles, and 1,2-disubstituted benzo[d]imidazoles.

Mesoporous silica (SBA-15)-supported iridium catalysts are prepared by grafting of the newly developed cyclometalated iridium 2-aryl benzoxazole complexes with 3-(triethoxysilyl)-propyl-isocyanate (TEPIC) as a linker. The supported catalysts are characterized by solid-state NMR spectroscopy, small-angle X-ray scattering (SAXS), nitrogen physisorption, FTIR spectroscopy, and electron microscopy analysis, which indicate that the coordination environment of the iridium center as well as the two-dimensional hexagonal pore structure of SBA-15 is maintained after the immobilization. These supported catalysts have been successfully applied to the selective transfer hydrogenation of quinoline derivatives to 1,2,3,4-tetrahydroquinolines (THQs) with formic acid in pure water. Moreover, by simply adapting the amount of formic acid used, N-formyltetrahydroquinolines (FTHQs) could be selectively synthesized from quinolines in two-step, one-pot transfer hydrogenation/N-formylation reactions with these supported catalysts. Notably, these supported catalysts showed better catalytic reactivity than their homogeneous analogs, and they can be easily reused 12 times in the transformation of quinoline to N-formyltetrahydroquinoline (FTHQ) without significant loss of activity.

Fundamental understanding of the real catalytic species in water oxidation is a major knowledge gap that must be overcome in order to develop artificial water splitting systems and produce chemical fuels from solar energy. In an effort to analyze the transformation and catalytic resting state of [Cp*Ir(pmNHC)Cl]Cl [pmNHC = 1-(2-pyrimidyl)-3- n -butylimidazol-2-ylidene, Cp* = pentamethylcyclopentadienyl] in water oxidation using potassium peroxymonosulfate (Oxone) as primary oxidant, we found the precatalyst evolved into blue solution when a small amount of Oxone was added while further oxidation yield purple solution. These species have been proven to be homogeneous and they remain active in water oxidation. 1 H NMR profiles and MALDI-MS data suggested a rapid oxidation of the Cp* ligand to acetone, formic and acetic acid. 1 H NMR, TEM-EDX as well as MALDI-MS data indicated a continuous degradation of pyrimidyl, butyl and NHC groups. MALDI-MS, XANES and 17 O NMR spectroscopy data of the blue species are most consistent with an iridium(III) compound with two waters, one dioxygen and pmNHC group. The catalytic resting purple species probably consists of an iridium(III) complex with three waters, one chloride and one bicarbonate ligand. Besides, the presence of a small amount of iridium aqua ion oligomers was observed in the purple species. The formation of polymers and nanoparticles is likely to be inhibited by the acid environment.

Three highly efficient adsorbents Pb-IIMS-SBA-15, Pb-IIMS-MCM-41 and Pb-IIMS-FDU-12 for Pb(II) were prepared by grafting the functional monomer 4-(di (1H-pyrazol-1-yl) methyl) phenol (DPP) on corresponding mesoporous silicas with Pb(II) as temple. All these three Pb(II) ion-imprinted mesoporous silica (Pb-IIMS) were characterized by Fourier transform-infrared spectroscopy (FT-IR), solid-state 29 Si and 13 C NMR spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), N 2 adsorption–desorption analysis and small angel X-ray diffraction (XRD). The adsorption experiments revealed three Pb-IIMS all possessed considerable adsorption performance for Pb(II), their adsorption profiles obeyed pseudo-second-order kinetics and Langmuir isotherm model. Compared with their corresponding non-imprinted materials, three Pb-IIMS displayed satisfactory selectivity to Pb(II) over seven competing metal ions. Among them, Pb-IIMS-MCM-41 particularly owned outstanding adsorption performance and selectivity, the maximum adsorption capacity as high as 344.8 mg g −1 , as well as excellent reusability through twelve adsorption-desorption cycles. Additionally, Pb-IIMS-MCM-41 was employed as packing material to construct a solid-phase extraction column for detection of Pb(II), which exhibited detection limit of 0.015 μg L −1 , then method was successfully applied to the removal and determination of trace Pb(II) in practical water samples.

In this study, an immobilization strategy for magnetic cross-linking enzyme aggregates of lipase B from Candida antarctica (CALB) was developed and investigated. Magnetic particles were prepared by conventional co-precipitation. The magnetic nanoparticles were modified with 3-aminopropyltriethoxysilane (APTES) to obtain surface amino-functionalized magnetic nanoparticles (APTES&ndash, Fe3O4) as immobilization materials. Glutaraldehyde was used as a crosslinker to covalently bind CALB to APTES&ndash, Fe3O4. The optimal conditions of immobilization of lipase and resolution of racemic 1-phenylethanol were investigated. Under optimal conditions, esters could be obtained with conversion of 50%, enantiomeric excess of product (eep) &gt, 99%, enantiomeric excess of substrate (ees) &gt, 99%, and enantiomeric ratio (E) &gt, 1000. The magnetic CALB CLEAs were successfully used for enzymatic kinetic resolution of fifteen secondary alcohols. Compared with Novozym 435, the magnetic CALB CLEAs exhibited a better enantioselectivity for most substrates. The conversion was still greater than 49% after the magnetic CALB CLEAs had been reused 10 times in a 48 h reaction cycle, both ees and eep were close to 99%. Furthermore, there was little decrease in catalytic activity and enantioselectivity after being stored at &minus, 20 &deg, C for 90 days.

Four mesoporous SBA-15-immobilized N-heterocyclic carbene (NHC) palladium catalysts with different nitrogen ligands were synthesized. The activity and recyclability of the catalysts were investigated in Suzuki–Miyaura cross-coupling reaction of typical aryl chlorides and arylboronic acids. Bulky NHC moiety was essential for efficiency, while tethering of nitrogen ligands on both support and NHC group could dramatically improve recyclability of the catalysts. The strategy offers an alternative strategy for designing highly efficient and recyclable immobilized catalysts. Mesoporous silica-immobilized palladium catalysts with the bulky N-heterocyclic carbene and tethered “throw-away”nitrogen ligands were found to be highly efficient and recyclable for Suzuki–Miyaura coupling reaction of inactive aryl chlorides.

2-Arylbenzazoles are promising molecules for potential applications in medicine and material areas. Efficient protocols for direct regioselective functionalization of 2-arylbenzoxazoles are in high demand. Herein, we disclose a general method for selective ortho-olefination of 2-arylbenzo[d]oxazoles with alkenes enabled by versatile Cp*Rh(III) in high yields. This protocol features broad functional group tolerance and high regioselectivity. Intermolecular competition studies and kinetic isotope effect experiments imply that the oxidative olefination process occurs via an electrophilic C-H activation pathway. The molecular structure of the m-fluoro-substituted olefination product confirms regioselective C-H activation/olefination at the more hindered site in cases where the meta F atom or heteroatom substituent existed. Apparent torsion angles were observed in the structures of mono- and bis-olefination products, which resulted in distinct different chemical shifts of olefinic protons. Additionally, two gram-scale reactions and further transformation experiments demonstrate that this method is practical for synthesis of ortho-alkenylated 2-arylbenzoxazole derivatives.

Technical analysis was used to analyze the roasting of molybdenum concentrate on the basis of thermal balance test of rotary furnaces used for Roasting, and the results indicate that, on the condition of commercial production, the Roasting of MoS2 can occur spontaneously because the heat of reaction is so much that proper cooling measures should be adopted in case overheating happens. According to above analysis, carbon-free roasting technology of molybdenum concentrate was proposed in this paper. The results, which come from thermal balance test and technical analysis of rotary furnaces used for carbon-free roasting of molybdenum concentrate, indicate that outer heat source used in traditional Roasting technology is not needed in carbon-free roasting technology, because enough heat is generated during Roasting to ensure spontaneous reaction. In fact, heating is not needed in operating process except at the beginning, to make molybdenum concentrate catching fire, and when reaction completing, to remove residual sulphur. The technology in this paper is obviously advantageous in aspects of energy saving, output, quality of production, heat loss, the concentration of SO2 in flue gas, etc. and will have remarkable environmental benefits, economic benefits and social benefits.