[en] With the continuous development and progress of computer technology, nuclear power plant instrumentation control system will use more and more digital technology to replace analog technology. In order to ensure the safe operation of nuclear power plants, strict quality management is required for hardware and software in digital instrumentation control systems. Verification and Validation (hereinafter V&V) is an important means to ensure the quality of application software in digital instrumentation control systems. From the customer's perspective, choosing a suitable implementation team to complete the V&V work and effectively supervising it is a necessary condition to ensure the effective implementation of V&V activities and to ensure the quality of the products supplied. Based on the experience of previous nuclear power plant engineering practices and based on the study and understanding of laws and regulations and standards, this paper puts forward the common requirements that the author would insist on how to choose an appropriate V&V implementing organization to carry out the corresponding activities according to the regulations and standards, as well as the criteria for its judgment and the customer's supervision and management methods. It is of great value and significance for customer or general contractor of Digital Instrument Control System (hereinafter DCS) to select the suitable V&V implementation organization / team as well as the customer's supervision and management. (author)

[en] A series of polyamidoamine (PAMAM) immobilized TEMPO macromolecular catalysts were prepared by condensation reduction reactions between carbonyl groups in 4-O-TEMPO and primary amines in PAMAM. The macromolecular catalyst and NaBr/NaClO were used as catalytic system for selective oxidation of cellulose in aqueous medium. Effects of various factors, such as TEMPO loading ratios and PAMAM generations, were studied on the catalytic performances. Compared with free TEMPO, the macromolecular catalyst with less than 50 % TEMPO loading ratio had a higher reaction rate in the initial stage of the reaction. Especially, the reaction rate of G1.0 PAMAM with 30 % TEMPO loading ratio was comparable to free TEMPO in the whole reaction process. Its cellulose oxidation degree (or catalytic activity) was also equivalent to the level of free TEMPO. Interestingly, the cellulose depolymerization degree of macromolecular catalyst was not affected by the cellulose oxidation degree and was lower than that of free TEMPO. The macromolecular catalyst could be recycled efficiently by the combination of supernatant circulation and salting-out extraction, and the recycling performance was excellent.

[en] Magnetic nanoparticles (MNPs) modified by polyamidoamine (PAMAM)-immobilized 2,2,6,6-tetramethyl-1-piperidinyl-oxyl (TEMPO) as recoverable catalysts for catalytic oxidation of polyethylene glycol were designed and prepared, which were expected to combine the advantages of easy recovery of MNPs and high activity of PAMAM-immobilized TEMPO. The catalysts of MNPs modified by PAMAM-immobilized TEMPO (MNPs-PAMAM-T) were characterized by Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analyzer (TGA), and transmission electron microscopy (TEM). The mean particle size of MNPs was about 10 nm. MNPs-PAMAM-T/NaBr/NaClO was used as catalytic system for catalytic oxidation of monomethoxy poly (ethylene glycol). The catalytic performances were affected by the loading amounts of TEMPO and PAMAM generations. It was shown that the catalyst with TEMPO loading of 5.198 mmol/g using G2.0 PAMAM-modified MNPs as carrier had the best catalytic performance, which could be up to 94% of the free TEMPO level. The efficient recovery of catalyst could be achieved by magnetic separation and the recycling performance was good.

[en] As a Li-ion battery anode, the active substance with a porous nanostructure can be endowed with a high electrochemical performance because of its porosity and remarkable surface area. In this paper, the thermal decomposition of zinc–cobalt binary oxalate precursors, precipitated from a solvothermal medium of ethanol and water (75/25, v/v) at 100 °C, has been performed to synthesize phase-pure ZnCo₂O₄ spinels, thoroughly giving porous and rod-like configurations with an average length of a few micrometers. Interestingly, each of the as-obtained porous microrods has been well characterized to consist of ∼35.2-nm single-crystalline nanoparticles with polydisperse interspaces. More interestingly, porous ZnCo₂O₄ microrods can deliver an initial specific discharge capacity of 1,293.7 mAh g⁻¹ with the coulombic efficiency of 76.8 % at 0.2 A g⁻¹, reaching a value of 937.3 mAh g⁻¹ over 100 discharge–charge cycles. Even at a high current density of 2.0 A g⁻¹, the porous ZnCo₂O₄ nanostructures can still possess a reversible discharge capacity of ∼925.0 mAh g⁻¹, further assigned to the synergistic effect of Zn- and Co-based oxide components. Anyway, the facile oxalate precursor method can realize the controlling synthesis of porous and rod-like ZnCo₂O₄ nanostructures with a high electrochemical performance

[en] With the improvement of living standards, cancer has become a great challenge around the world during last decades, meanwhile, abundant nanomaterials have been developed as drug delivery system (DDS) or cancer theranostic agents (CTAs) with their outstanding properties. However, low multifunctional efficiency and time-consuming synthesis limit their further applications. Nowadays, green chemistry, in particular, the concept of atom economy, has defined new criteria for the simplicity and efficient production of biomaterials for nanomedicine, which not only owns the property of spatio-temporal precision imaging, but also possess the ability to treat cancer. Interestingly, metal-organic framework (MOF) is an excellent example to meet the requirements behind this concept and has great potential for next-generation nanomedicine. In this review, we summarize our recent researches and inspiring progresses in designing DDS and CTA built from MOF, aiming to show the simplicity, control, and versatility, and provide views on the development of MOF-based nanomedicine in the future. (topical review)

[en] The terahertz (THz) temporal waveform and spectrum from a longitudinal electrically biased femtosecond filament is studied experimentally. The initial direction of the electron motion inside the unbiased filament plasma is deduced from the transformation of the THz temporal waveform with applied fields of opposite polarities. Furthermore, a spectrum shift to lower frequency of the THz spectrum is observed in the presence of a biased field. It agrees well with theoretical predictions. (paper)

[en] A simple method, reconstruction of calcinated layered double hydroxides (CLDH) in an organic (ethanol)-water mixed solvent medium containing drug, was developed to intercalate partially a non-ionic and poorly water-soluble drug (camptothecin) into the gallery of layered double hydroxides (LDHs) to form the drug-LDH composites. The purpose of choosing organic-water mixed solvent is to increase remarkably the solubility of camptothecin (CPT) in the reconstruction medium. A probable morphology of CPT molecules in the gallery of LDHs is that CPT molecules arrange as monolayer with the long axis parallel to the LDH layers. The in vitro drug release from the composites was remarkably lower than that from the corresponding physical mixture, which shows these drug-inorganic composites can be used as a potential drug delivery system. - Graphical abstract: A simple method, reconstruction of calcinated LDHs in an organic-water medium containing drug, was developed to intercalate non-ionic and poorly water-soluble camptothecin into the gallery of LDHs.

[en] In this paper, the intercalation of 5-fluorocytosine (5-FC) into a layered inorganic host, Zn-Al layered double hydroxide (LDH), has been carried out using coprecipitation method to obtain 5-FC/LDH nanohybrids. The intercalated amount (A_In) of 5-FC into the LDH is remarkably dependent on the molar ratio (R_F/M) of 5-FC to metal ions and the pH of coprecipitation system. The morphology of 5-FC molecules in 5-FC/LDH nanohybrids is dependent on the A_In. It is interestingly found that the morphology of the nanohybrid particles may be changed with the increase of R_F/M from hexagonal plate particles to threadlike particles. The in vitro drug release from the nanohybrids is remarkably lower than that from the corresponding physical mixture and pristine 5-FC at either pH 4.8 or pH 7.5. In addition, the release rate of 5-FC from the nanohybrid at pH 7.5 is remarkably lower than that at pH 4.8, this is due to a possible difference in the release mechanism. The obtained results show these drug-inorganic nanohybrids can be used as a potential drug delivery system. - Graphical abstract: The 5-fluorocytosine (5-FC) has been intercalated into layered double hydroxide using coprecipitation method. The morphology of 5-FC molecules in obtained nanohybrids was dependent on the intercalated amount of 5-FC. The in vitro drug release from the nanohybrids was remarkably lower than that from the corresponding physical mixture, which shows these drug-inorganic nanohybrids can be used as a potential drug delivery system

[en] Highlights: • The effective degradation of CT can be achieved in mZVAl/CA system. • The mZVAl corrosion reaction was enhanced during SC complexation corrosion process. • The electron utilization efficiency in the SC system can reach up to 94%. • SC did enhance the sustainable utilization property of mZVAl for CT degradation. Carbon tetrachloride (CT) is highly toxic and recalcitrant in groundwater. In recent years, zero-valent aluminum (ZVAl) is highly reductive but limited by its surface passivation film. One of the effective ways to overcome this bottleneck is to add ligands. In this paper, compared with several other ligands, sodium citrate (SC), a natural organic ligand, was introduced to enhance microscale ZVAl (mZVAl) reactivity for the reductive degradation of CT. The results showed that the SC system could effectively reduce but not completely dechlorinate CT and electron utilization efficiency was as high as 94%. However, without ligands, mZVAl is chemically inert for CT degradation. Through SEM-EDS, BET, XRD, and XPS characterizations and H₂ evolution experiments, enhanced mZVAl surface corrosion at the solid-liquid interface of mZVAl/SC system was verified. SC participated in the complexation corrosion reaction with surface inert film to form Al[Cit] complex, which made internal Al⁰ active sites exposed and then promoted mZVAl corrosion. In the five consecutive reuse experiments of mZVAl, CT can be completely degraded, which indicates that mZVAl, with the help of SC, has excellent sustainable utilization efficiency.