cell−cell communication, the invasion of pathogens. [1] Many bacteria have evolved specific recognition structures such as fimbriae that bind to host cell glycoconjugates, and these strong affinities of the macromolecular glycans with the bacteria receptors are mainly the result of polyvalent interactions. [2] Controlling the recognition between bacteria and surfaces of glycopolymer based polyvalent scaffolds that constitute the "glycocode" is essential to further understand these processes and to develop anti-infection strategies. [3] Inflamed tissue exhibits several degrees above body temperature due to an increased metabolic rate, [4] which may provide a stimulus for controlling the sweet-talking of bacteria with polyvalent scaffolds. Therefore, to design thermoresponsive polyvalent scaffolds that optimally mimic and adapt to the dynamics of receptors on bacteria membrane would enable intervention in infection caused by bacteria. [5] To date, all thermo-triggerable polyvalent scaffolds are relied on the combination of lower critical solution temperature (LCST)responsive polymers and choice of sugar moieties. [3b,6] For example, Schmidt et al. have recently found the binding affinity of LCST glycopolymers increases above their LCST. [6a] Such Specific recognition and strong affinities of bacteria receptors with the host cell glycoconjugates pave the way to control the bacteria aggregation and kill bacteria. Herein, using aggregation-induced emission (AIE) molecules decorated upper critical solution temperature (UCST) polyvalent scaffold (PATC-GlcN), an approach toward visualizing bacteria aggregation and controlling bacteria-polyvalent scaffolds affinities under temperature stimulus is described. Polyvalent scaffolds with diblocks, one UCST block PATC of polyacrylamides showing a sharp UCST transition and typical AIE behavior, the second bacteria recognition block GlcN of hydrophilic glucosamine modified polyacrylamide, are prepared through a reversible addition and fragmentation chain transfer polymerization. Aggregated chain conformation of poly valent scaffolds at temperature below UCST induces the aggregation of E. coli ATCC8739, because of the high density of glucosamine moieties, whereas beyond UCST, the hydrophilic state of the scaffolds dissociates the bacteria aggregation. The sweet-talking of bacteria toward the polyvalent scaffolds can be visualized by the fluorescent imaging technique, simultaneously. Due to the specific recognition of polyvalent scaffolds with bacteria, the photothermal agent IR780 loaded PATC-GlcN shows the targeted killing ability toward E. coli ATCC8739 in vitro and in vivo under NIR radiation.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/smll.202107374.

The perforation field all over the world has been puzzled by the difficultquestion that the perforating system goes off on the ground while doing oil and gas well perforating operation. Besides necessary safety education and strictlyoperating rules, regulations & procedures, the perforating operations should be guaranteed by systematic and necessary safety techniques. This paper analyzed the non-safe factors existed in the perforating operations in the aspect of the dangerous source, safety control and the reliability evaluation of the perforation system, and presented the corresponding countermeasure to each links. All these countermeasure and measurement have been tested and successfully applied for over ten thousand times in more than 4000 wells, goods results have been obtained. Introduction The cause that the perforating system explodes on the ground is complicated, but the detonator is the source of explosion. The general techniques and measurement is difficult to get the desired result. In order to prevent or decrease the surface explosion, Shengli Well Logging Company successfully made a set of pressure operated safe system for perforating operation through many year practices. The concrete method is as follows: Increasing the immunity of detonator to external interference by enabling the filament of detonator both in normal open status to the outside and in short status to the inside. The whole assembly is shielded inside metal housing. This detonator has the abilities to prevent against ESD, RF interference, induced current from stray voltage, human errors. Pressure operated anti-explosion device is built in between detonator and the secondary explosives (detonating cord and charges). Even if accidental firing of the detonator, the shock wave will be resisted by anti-explosion device, the secondary explosives will not be initiated. The safety of operating personnel will be therefore guaranteed.

High purity SiB4 powder is the key raw materials for high temperature resistant coating of rigid ceramic insulating tile, which plays the role of forming a dense coating and self-healing in the coating. Therefore, to obtain SiB4 powders with high performance and high purity at the same time can solve the problem of raw materials for high temperature resistant coating in China. However, the preparation process of SiB4 powder is complex, and no domestic manufacturer can produce it, which greatly limits the development of related industries in China. The relationship between SiB4 phase purity and boron-silicon ratio of raw materials, particle size and sintering process parameters in the synthesis of high-purity SiB4 powders was explored. The experimental results show that the yield of SiB4 can be significantly improved and the decomposition of SiB4 can be inhibited by adjusting the crystallinity of boron powder, particle size of raw material, sintering process parameters and the ratio of boron to silicon. When 1μm boron powder and 1μm silicon powder are used, the ratio of boron to silicon is 3.5:1, and the sintering process is 1320 °C - 2h, the high purity sib4 powder with only SiB4 phase detected by XRD phase analysis can be prepared after acid washing. On this basis, the high temperature oxidation characteristics of the prepared SiB4 powder were studied. The experimental results show that SiB4 powder can be oxidized at 1100 °C to form B2O3-SiO2 glass phase, which proves that it has better high temperature oxidation performance. In conclusion, it was proved that the prepared SiB4 powder had high purity and excellent high temperature resistance, which could be used for further production research.

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Formation of Ynones. -(Het)aromatic and aliphatic acyl chlorides undergo cross--coupling reaction with aromatic and aliphatic terminal alkynes to form ynones. A palladium bipyridyl complex grafted onto nanosized ordered mesoporous silica MCM-41 is used as the efficient catalyst whereas Et 3 N acts as base and solvent. To afford (IIIa) catalyst loading can be lowered to 0.002 mol% to give the desired product with high yield but a long reaction time is required. The new method is also applicable to very bulky substrates as (IX) albeit the product is isolated with poor yield. -(CHEN,