Research on Crucial Manufacturing Process of Rigid-Flex PCB

The main characteristics, applications, the emphases of manufacturing process are introduced, and the research of new product of rigid-flex Printed Circuit Board （PCB） is also described. In particular, the plasma desmear process, which is the crucial problems of manufacturing process, is discussed in detail. Samsung 4-layer rigid-flex PCB has been developed successfully, and the qualification rate reaches to 89.4%.

Studies on the Activities of Electrophilic Sites on Benzene Ring of 4-Substituted Anilines and Their Acyl Compounds with Multiphilicity Descriptor

In this paper, the activities of electrophilic sites on benzene ring of 4-substituted anilines and their acyl compounds were studied with the quantitative indicator of multiphilicity descriptor. Four substituents were synthe- sized with microwave irradiation in good yields to verify the quantitative analysis data. Friedel-Crafts acylation was carried out by the microwave method for the first time.

Size and shape controllable preparation of graphene sponge by freezing, lyophilizing and reducing in container

Graphene sponge(GS) is a porous 3D structure of graphene. Although hydrothermal reduction, chemical vapor deposition, solution reduction and high temperature annealing could be used for the preparation of GS, the size and shape cannot be well controlled. Herein, we reported a facile method to prepare GS under mild condition in a size and shape controllable way. Graphene oxide was lyophilized to form the spongy structure and reduced by steamy hydrazine hydrate to produce GS. The size and shape of GS prepared were nearly identical to that of the container. The reduction degree of GS could be regulated by the reduction temperature and time.

Recent catalytic syntheses of trifluoromethylthio-containing organic compounds by transition metals,chiral organocatalysts,and photocatalysts

This review summarizes the recent advances in the catalytic syntheses of CFS-containing organic molecules using various nucleophilic or electrophilic trifluoromethylthiolating reagents.C-halogen and C—H bonds in various molecules have been transformed to C—SCFbonds by transition-metal-catalyzed reactions,such as cross-coupling of aryl halides.Enantioselective reactions controlled by chiral metal complexes or chiral organocatalysts have afforded many trifluoromethylthiolated chiral architectures,such as β-ketoesters and oxindoles.Very recently,visible-light-induced photoredox trifluoromethylthiolations have been developed,providing versatile CFS-containing structures efficiently.

Hydrothermal reduction of graphene oxide by glucose for the preparation of graphene/polyester staple sponge and its applications in oil spill cleanup

Graphene/polyester staple sponge(GPSS)is a high-performance adsorbent for the cleanup of crude oil spill,but the use of hydrazine hydrate as the reducing agent for the preparation of GPSS is not friendly to the environment.Herein,we reported that graphene oxide/polyester staple composite could be hydrothermally reduced by bioresource glucose to prepare GPSS of similar performance.GPSS could be applied in the absorption of oils and organic solvents thanks to its large pore volume and hydrophobicity.The absorption capacity of the novel glucose-reduced GPSS was competitive to those of the most effective absorbents for oil spill cleanup.The used GPSS could be easily regenerated by soaking in ethanol to remove the absorbed oil.The green synthesis,high oil absorption performance and easy recycling of the glucose-reduced GPSS make it a good candidate for cleaning oil spills.

A novel method to assess the effect of diagenesis on fossil teeth:Rare earth element signatures

An attempt was made to test the validity of the signatures of rare earth elements （REE） as a tool to judge the effect of diagenesis on fossil teeth. Sample REE contents and features of fossil teeth and sediments from Jinsha Relics, Sichuan, Southwest China were analyzed. The difference in REE content between fossil teeth is significantly greater than that between sediments at the Jinsha Relics. Chondrite-normalized REE patterns showed that obvious LREE enrichment and strong Ce and HREE depletion occurred in all fossil teeth samples. Meanwhile δCe and δEu values varied more dramatically in fossil teeth than in sediments. Accordingly, low content, LREE enrichment, strong Ce depletion, the significantly positive correlation between LREE/HREE and δCe, and unchanged （La/Yb）N demonstrated that the fossil teeth from Jinsha Relics have not been contaminated by diagenesis. The REE signature might be a potential proxy to assess the effect of diagenesis on fossil teeth.

Research on Chemical Reactivity of Nitrotriazolam in Its Process of Preparation

Chemical reaction possibility was described quantitatively for the case of nitrotriazolam preparation with 2-clonazepam by using the data of two quantum chemical reactivity indices: net electrophilicity index and Wiberg bond order. Furthennore, relevant reaction mechanism was derived from tlie aspect of quantum chemistry. The results show that the indices used can quantitatively explain the chemical reactivity and reaction mechanism of the nitrotriazolam preparation. To validate the universal applicability of the proposed approach, the authors continued to use the quantum chemical reactivity indices to describe some classic chemical reactions, expecting to predict major issues related to physical organic chemistry, such as new chemical reactions and their mechanisms.

Enantioselective synthesis of 2-amino-3-nitrile-chromenes catalyzed by cinchona alkaloids:A remarkable additive effect

2-Amino-3-nitrile-chromenes with potential antitumor activity were constructed by a novel catalytic system. In combination with a-naphthol, quinine could effectively promote the Michael-cyclization process of malononitrile with functionalized chalcones in high yields and moderate to good enantioselectivity（up to 84% ee）. It is notable that the enantioselectivity could be greatly improved when a-naphthol was employed as additive.

Organocatalytic cascade 1,6-conjugate addition/annulation/tautomerization of functionalized para-quinone methides： Access to chiral 2-amino-4-aryl-4H-chromenes

A novel organocatalytic cascade process initiated by 1,6-conjugated addition has been successfully developed. A range of pharmaceutically active 2-amino-4-aryl-4H-chromenes were readily obtained in high yields（88%-99%） and excellent enantiopurities（86%-99% ee）. The functionalized para-Quinone methides（p-OMs） could be facilely obtained.

Fe_3O_4@C nanoparticles as high-performance Fenton-like catalyst for dye decoloration

Water pollution has become serious environmental problem nowadays. Advanced oxidation processes(AOP) have been widely applied in water treatment.However, traditional Fenton reaction based on Fe2﹢-H2O2 system has obvious drawbacks, which limit its applications In this study, magnetic Fe3O4core-C shell nanoparticles(Fe3O4@C NPs) were prepared for the decoloration of methylene blue(MB) via the co-precipitation followed by the hydrothermal dehydrogenation of glucose. Fe3O4@C NPs showed high catalytic activity of the decoloration of MB through the decomposition of H2O2 in Fenton-like reactions. Fe3O4@C NPs had much higher activity than bare Fe3O4 cores, suggesting the coating of carbon enhanced the catalytic activity. The performance of Fe3O4@C NPs was better at lower pH and higher temperature, but was significantly inhibited in the presence of radical scavenger tertiary butanol. Fe3O4@C NPs could be magnetic separated and regenerated, and maintained with very good catalytic activity. The implication for the applications of Fe3O4@C NP-catalyzed Fenton-like reactions in water treatment was discussed.

TiO_2-doped Fe_3O_4 nanoparticles as high-performance Fenton-like catalyst for dye decoloration

Fenton reaction based on Fe2+-H2O2 system has been widely applied in water remediation, but the obvious drawbacks largely hinder its practical uses. Alternatively, heterogeneous nanomaterials with proper surface modification could be used as Fenton-like catalysts. Surface doping of Ti O2 could concentrate the pollutants surrounding the Fe3O4 catalyst, which might benefit the catalytic performance of Fe3O4. Herein, we reported that Ti O2-doped Fe3O4 nanoparticles(NPs) could be used as high-performance Fenton-like catalyst for dye decoloration in near neutral environment, where the doping of Ti O2 on Fe3O4 surface dramatically improved the catalytic activity of Fe3O4 in Fenton-like reaction. Ti O2-doped Fe3O4 NPs catalyzed the decomposition of H2O2 to oxidize methylene blue without external energy supply, resulting in effective decoloration. Ti O2-doped Fe3O4 NPs showed high catalytic activity under various p H values and even in the presence of radical scavenger. More catalysts and H2O2 would facilitate the decoloration. At higher temperature, the decoloration became faster and more effective. The implication to the environmental applications of Ti O2-doped Fe3O4 NPs is discussed.

A smart cluster paradigm based Mo-containing polyoxometalate as a new therapeutic strategy for tumor-specific photothermal therapy

A desirable near-infrared(NIR)photothermal agent based on Mo-based polyoxometalate cluster with self-adaptive electronic structure for tumor acidity/reducibility-specific therapy was reported in a paper on Journal of the American Chemical Society[1].This‘‘small-big"cluster paradigm displayed the capacity of self-assemble to big molecules under activation both the