查找使用阿拉丁产品的科研文献

On the nature of the optimum cleaning concentration for dairy fouling: High NaOH concentrations inhibit the cleavage of non-covalent interactions in whey protein aggregates

Liyuan Fan,Xiao Dong Chen,Ruben Mercadé-Prieto

The dairy industry has long known that highly concentrated alkaline solutions should not be used to clean whey protein rich fouling deposits. At >0.1 mol L −1 NaOH dissolution and cleaning rates decrease markedly to very low values, particularly at low-mid temperatures. It is shown here that it is caused by the incapacity of the hydroxide ion to destroy non-covalent interactions between protein aggregates at high alkali concentrations. HPLC is used to quantify the breakdown kinetics of soluble whey protein isolate (WPI) aggregates. Results show that the large aggregates breakdown kinetic constant is strongly reduced at >0.25 mol L −1 NaOH, but also at high protein concentrations. Moreover, large aggregates become increasingly stable for long times at ≥0.5 mol L −1 NaOH. The kinetic analysis predicts that large protein aggregates would be fully stable at 0.085–0.105 g WPI/g solution, explaining the dissolution threshold observed in macroscopic swelling studies.

Effect of polyethylene glycol on corrosion of fresh macroporous silicon in 1.0 M NaOH and application in determination of porosity and thickness by gravimetric measurement

Chuan Lai,Xiaogang Guo,Mingfeng Wang,Jiajun He,Zhuli Wang,Bin Xie

Tailored NaOH/phytic acid-driven method for fabricating carvacrol-loaded zein/trehalolipid nanoparticles with higher processing adaptability: Utilizing dual critical pH of wall and core materials

Jiyao Zhang,Shuyi Liu,Yajing Qi,Zhongwei Chen,Bin Xu

Encapsulating within zein/trehalolipid nanoparticles (Z/TL) via NaOH/phytic acid-driven method (PAPD) can improve water solubility and stability of carvacrol (CAR). However, this technique still has limitations including empirically determined parameters and potential risk of core material degradation. In this respect, we introduced a strategy of positioning dual critical pH based on specific attributes of wall and core materials. The finest alkalization endpoint for Z/TL was determined by monitoring conformational changes across pH 7–12. Meanwhile, the suitable pH of deprotonation was identified by assessing pH-dependent water solubility and chemical stability of CAR. Obtained information was applied to modify PAPD into PAPD’. The colloidal properties, encapsulation efficiency (EE), loading capability (LC), environmental stress resistance, and in vitro release behavior of nanoparticles prepared using PAPD’ and PAPD were systematically compared. The optimal alkalinization endpoint for Z/TL was determined to be pH 11.25. where the degree of hydrolysis would not increase further, but the acceleration of increase in aqueous solubility would reach its maximum. The optimal pH of deprotonation for CAR was pH 11, balancing high solubility with controllable degradation. PAPD’-nanoparticles exhibited a smaller size (99.36 nm), higher ζ-potential (−43.91 mV), and improved EE/LC (97.95 %/29.39 %). Enhanced stability, along with a sustained release profile were demonstrated. Consumption of NaOH/PA was also reduced while maintaining required efficacy. Overall, customized PAPD’ not only improves the processing adaptability and flexibility of fabricating protein-based nanoparticles but also provides a theoretical framework and practical paradigm for the rational design of nanocarriers for bioactive compounds.

A method on the induction of piezoelectricity of PVDF by NaOH: Induced PVDF as ultrafiltration base membrane in interfacial polymerization to enhance the rejection of NaCl

Yuliang Chen,Wenmin Wang,Ying Liang,Chen Chen,Rui Meng,Libo Ba,Yuliang Wu,Yijiang Liu,Weiwei Huang,Fei Yang,Jun Cheng,Xuesong Yi

Nanofiltration technology has garnered significant attention due to its potential to address global water scarcity. However, the low rejection rates of monovalent salts, such as NaCl, have limited the broader application of nanofiltration membranes. In this study, polyvinylidene fluoride (PVDF) powder was chemically modified by a saturated sodium hydroxide solution to the formation of a phase transition from the non-polar α-phase to the polar β-phase. The NaOH treatment promoted this phase transition by disrupting the crystal structure and enhancing molecular polarity, thereby inducing piezoelectric properties in the membrane. The modified PVDF was then formed as ultrafiltration substrate to fabricate a nanofiltration membrane with a dual-layer charge structure through surface charge-regulated interfacial polymerization. The NaOH-induced chemical modifications significantly improved both piezoelectric effect and ion rejection performance. The Piezo-PVDF nanofiltration membrane exhibited a 60 % rejection rate for 1 g/L NaCl, with an optimal water flux of 13.5 L m 2  h −1  bar −1 . This study demonstrates how NaOH-induced phase transition and piezoelectric activation optimize charge distribution across the membrane, leading to enhanced desalination performance. These findings provide new insights into the chemical mechanisms driving PVDF membrane modification and offer a strong theoretical and experimental foundation for the development of efficient and cost-effective desalination technologies.

Achieving time-dependent and color-tunable ultralong room temperature phosphorescence through sodiation reconfiguration for dynamic 5D information encryption

Li Ya Liang,Ya Ting Gao,Shuai Chang,Jian Lv,Bin Bin Chen,Da Wei Li

Achieving dynamic optical tunability of ultralong room temperature phosphorescence (RTP) materials is critical for the design of advanced multi-level information encryption. In this work, we develop a facile metal–organic thermal polymerization strategy for the preparation of aluminium/phenylalanine phosphorescent materials (Al/Phe-PMs) with a production capacity on a kilogram scale. The Al/Phe-PMs show an ultralong lifetime of up to 1015.3 ms, with a phosphorescent quantum yield of 7.98%. Most importantly, the Al/Phe-PMs have a unique time-dependent phosphorescence color (TDPC) phenomenon because of the presence of multiple emission peaks with diverse decay times, causing the dynamic transition of RTP color from yellow to chartreuse and then to green with the extension of the decay time. Furthermore, NaOH can be used for effectively regulating the optical properties of Al/Phe-PMs, causing a great blue shift in RTP emission and a decrease in RTP efficiency. NaOH-stimulated color tunability is proven to be ascribed to the sodiation reconfiguration effect that results in the depolymerization of Al/Phe-PMs and the destruction of the rigid conformation. Benefitted by the advantages of both TDPC and color-tunability, the proposed Al/Phe-PMs can be designed for constructing dynamic colored 5D information encryption systems.

A novel magnetic sludge biochar was prepared by making full use of internal iron in sludge combining KMnO4–NaOH modification to enhance the adsorption of Pb (Ⅱ), Cu (Ⅱ) and Cd (Ⅱ)

Zhiliang Cui,Guoren Xu,Banu Ormeci,Jiayin Hao

This study synthesized novel magnetic biochar (PCMN600) by KMnO 4 –NaOH combined modification using iron-containing pharmaceutical sludge to remove toxic metals from wastewater effectively. Various characterization experiments of engineered biochar showed that the modification process introduced ultrafine MnO x particles on the carbon surface and resulted in higher BET surface area and porosity along with more oxygen-containing surface functional groups. Batch adsorption studies indicated that the maximum adsorption capacities of PCMN600 for Pb 2+ , Cu 2+ and Cd 2+ were 181.82 mg/g, 30.03 mg/g and 27.47 mg/g, respectively, at a temperature of 25 °C and pH of 5.0, which were much higher than that of pristine biochar (26.46 mg/g, 6.56 mg/g and 6.40 mg/g). The adsorption datums of three toxic metal ions fitted well to the pseudo-second-order model and Langmuir isotherm, and the sorption mechanisms were identified as electrostatic attraction, ion exchange, surface complexation, cation-π interaction and precipitation. The strong magnetic properties of the engineered biochar endowed the adsorbent with remarkable reusability, and after five cycles of recycling, PCMN600 still retained nearly 80% of its initial adsorption capacities.