One-Step Lining and Deacidification of Aged Newspapers with Double-sided Writing

2018 ◽  
Vol 39 (1) ◽  
pp. 1-18
Author(s):  
Meifang Zhang ◽  
Fuze Jiang
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Thermal Ageing ◽  
Wheat Starch ◽  
Time Increase ◽  
Visual Appearance ◽  
Folding Endurance ◽  
One Step ◽  
The One ◽  
Starch Paste

AbstractThe one-step lining and deacidification process of aged newspapers with double-sided writing combines deacidification and reinforcement processes. Wheat starch paste or carboxymethyl cellulose were prepared using an aqueous solution of Ca(OH)2. The newspapers were lined with Japanese tissue (9 g/m2), using the alkaline adhesive in order to mechanically reinforce the newspapers and at the same time increase the pH of the paper. After treatment, the pH value of the newspaper samples reached an ideal range between 8.0–8.5 when thew.1% Ca(OH)2was used. More notably, the Japanese tissue lining doubled strength and folding endurance. The treatment had little impact on the visual appearance of the writing and even increased the degree of whiteness of the paper. The increase of tensile strength and whiteness was not diminished even when the treated newspaper samples were exposed to accelerated thermal ageing.

Protecting group free synthesis of urea-linked glycoconjugates: efficient synthesis of β-urea glycosides in aqueous solution

2014 ◽  
Vol 12 (23) ◽  
pp. 3924-3931 ◽  
Author(s):  
Yoshiyasu Ichikawa ◽  
Takahiro Minami ◽  
Shohei Kusaba ◽  
Nobuyoshi Saeki ◽  
Yuta Tonegawa ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Protecting Group ◽  
Efficient Synthesis ◽  
Acidic Aqueous Solution ◽  
Step Process ◽  
One Step ◽  
The One

The one step process, involving reactions between urea and protecting group free d-glucose, N-acetyl-d-glucosamine or d-xylose in acidic aqueous solution, furnishes the corresponding β-urea glycosides.

Immobilization and Thermostability Characterization of Cephalosporin C Acylase

2013 ◽  
Vol 634-638 ◽  
pp. 682-688
Author(s):  
Kai Hua Han ◽  
Hui Luo ◽  
Yao Zhen Xie ◽  
Shun Yao ◽  
Yan Hong Chang ◽  
...  
Keyword(s):  
Immobilized Enzyme ◽  
Ph Value ◽  
Cephalosporin C ◽  
Sodium Phosphate Buffer ◽  
Cephalosporin C Acylase ◽  
Key Enzyme ◽  
One Step ◽  
Enzyme Dosage ◽  
The One

Some kinds of epoxy supports, LX1000-EP(C), LX1000-EP(D), LKZ-116, LKZ-118 and LKZ-126 were utilized to covalently immobilize cephalosporin C (CPC) acylase, the key enzyme in the one-step enzymatic process of 7-aminocephalosporanic acid (7-ACA) production. After preliminary carrier screening, the immobilized CPC acylase with LKZ-118 as the support shows the highest activity (115 U/g) suggesting its potential application in industrial 7-ACA production. The conditions of CPC acylase immobilized on LKZ-118 to achieve higher activity and thermostability of the immobilized enzyme were optimized by adjusting pH value, buffer concentration, enzyme dosage and immobilized time. The activity of immobilized enzyme was found to be optimal at pH 8.5, in 0.85 M sodium phosphate buffer when the enzyme dosage was 500 U/g and immobilization time was 28 h.

scholarly journals One-step Green Preparation of Nano-silver Aqueous Solution, Characterization, and Its Antibacterial Potential for Cut Carnation Flowers

2021 ◽  
Author(s):  
Zhenpei Pang ◽  
Hongmei Li ◽  
Guidong Lin ◽  
Yunhao Sun ◽  
Hongjun Zhou ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Visible Spectrum ◽  
Inhibitory Effect ◽  
Ion Source ◽  
Cut Flowers ◽  
Environmental Friendliness ◽  
Nano Silver ◽  
Strong Inhibitory Effect ◽  
One Step

Abstract The green synthesis of nano-silver (NS) has gained increasing attention owing to its cost-effectiveness and environmental friendliness. Herein, we have described a novel one-step green preparation method of stable NS aqueous solution using Tollens reagent as the silver ion source, D-fructose as the reduction agent, and polyvinyl pyrrolidone (PVP) as the stabilizing and capping agent. The optimum preparation parameters were 40 mL 10 g L−1 PVP, 100 mL 0.116 mol L−1 D-fructose, and 200 mL 0.001 mol L−1 Tollens at a reaction temperature of 25 °C for 2 h. The prepared NS solution had a pH value of 7.10, with approximately spherical NS particles in the range of 13.95–87.36 nm. The resulting NS solution was stable under normal temperature, boiling water bath, and acidic environment; however, it did not exhibit stability under an alkaline environment. The NS solution had a remarkable absorption peak at 410 nm in its ultraviolet visible spectrum. Moreover, it exerted strong inhibitory effect on the growth of the bacteria isolated from the vase water of cut carnation ‘Prince’ flowers. These findings indicate that the obtained NS aqueous solution is potentially a practical and effective antibacterial agent for preserving cut carnations and other cut flowers.

Photo Catalytic Reduction of Pb(II) Using Titanium Oxide PVA-Alginate Beads under Sunlight

2014 ◽  
Vol 606 ◽  
pp. 99-103 ◽  
Author(s):  
Ani Idris ◽  
Zohreh Majidnia
Keyword(s):  
Aqueous Solution ◽  
Titanium Oxide ◽  
Contact Time ◽  
Catalytic Reduction ◽  
Alginate Beads ◽  
Significant Loss ◽  
Photocatalytic Process ◽  
One Step ◽  
Presence And Absence ◽  
The One

Pb(II) which is considered a toxic and common pollutant to the environment was removed from the aqueous solution using the one step photo catalytic reduction with the help of titanium oxide PVA-alginate beads. The photo catalytic reduction was performed in the presence and absence of sunlight at pH 7 and Pb(II) concentration of 50mg/L at the equilibrium contact time of 180 min. The results revealed that the titanium oxide PVA-alginate beads were capable of removing 98% of Pb(II) from the aqueous solution within 150 min. The titanium oxide PVA-alginate beads can be separated from the aqueous solution after photocatalytic process and they can be reused for at least 7 times without significant loss in their initial properties.

A Study on the Rearrangement of Dialkyl 1-Aryl-1-hydroxymethylphosphonates to Benzyl Phosphates

2020 ◽  
Vol 24 (4) ◽  
pp. 465-471 ◽  
Author(s):  
Zita Rádai ◽  
Réka Szabó ◽  
Áron Szigetvári ◽  
Nóra Zsuzsa Kiss ◽  
Zoltán Mucsi ◽  
...  
Keyword(s):  
Quantum Chemical ◽  
Room Temperature ◽  
Phase Transfer ◽  
One Pot ◽  
Substrate Dependence ◽  
Triethylbenzylammonium Chloride ◽  
One Step ◽  
The Pudovik Reaction ◽  
The One ◽  
Solid Liquid

The phospha-Brook rearrangement of dialkyl 1-aryl-1-hydroxymethylphosphonates (HPs) to the corresponding benzyl phosphates (BPs) has been elaborated under solid-liquid phase transfer catalytic conditions. The best procedure involved the use of triethylbenzylammonium chloride as the catalyst and Cs2CO3 as the base in acetonitrile as the solvent at room temperature. The substrate dependence of the rearrangement has been studied, and the mechanism of the transformation under discussion was explored by quantum chemical calculations. The key intermediate is an oxaphosphirane. The one-pot version starting with the Pudovik reaction has also been developed. The conditions of this tandem transformation were the same, as those for the one-step HP→BP conversion.

A Simple Synthesis of the Anticancer Drug Altretamine

2020 ◽  
Vol 17 (8) ◽  
pp. 628-630
Author(s):  
Vu Binh Duong ◽  
Pham Van Hien ◽  
Tran Thai Ngoc ◽  
Phan Dinh Chau ◽  
Tran Khac Vu
Keyword(s):  
Aqueous Solution ◽  
Anticancer Drug ◽  
Potassium Hydroxide ◽  
Large Scale ◽  
Synthesis Method ◽  
Practical Method ◽  
Cyanuric Chloride ◽  
Simple Synthesis ◽  
High Yield ◽  
One Step

A simple and practical method for the synthesis on a large scale of altretamine (1), a wellknown antitumor drug, has been successfully developed. The synthesis method involves the conversion of cyanuric chloride (2) into altretamine (1) by dimethylamination of 2 with an aqueous solution of 40% dimethylamine and potassium hydroxide in 1, -dioxan 4in one step to give altretamine (1) in high yield.

One-step controlled synthesis of anisotropic gold nanostructures with aniline as the reductant in aqueous solution

2007 ◽  
Vol 309 (2) ◽  
pp. 518-523 ◽  
Author(s):  
Zhirui Guo ◽  
Yu Zhang ◽  
Lan Huang ◽  
Meng Wang ◽  
Jing Wang ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Gold Nanostructures ◽  
Controlled Synthesis ◽  
One Step

scholarly journals Selenium in wastewater can be adsorbed by modified natural zeolite and reused in vegetable growth

2021 ◽  
Vol 104 (2) ◽  
pp. 003685042110198
Author(s):  
Xiao Zhang ◽  
Xinyuan Li ◽  
Zihao Jin ◽  
Sadam Hussain Tumrani ◽  
Xiaodong Ji
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Soil Improvement ◽  
Pollutant Removal ◽  
Maximum Adsorption Capacity ◽  
Selenium Content ◽  
Water Release ◽  
Soil Release ◽  
Release Ratio ◽  
Water Pollutant

Modified natural zeolites (MNZ) are widely used in pollutant removal, but how to address these MNZ that have adsorbed pollutants must be considered. Selenium is an essential trace element for metabolism and is also a water pollutant. Selenium is adsorbed in the water by MNZ in this study first. Then the Brassica chinensis L. was planted in the soil which contains the MNZ loaded with selenium (MNZ-Se) to explore selenium uptake. MNZ-Se release tests in water and soil were also considered. The results showed the following: (1) The maximum adsorption capacity of MNZ for selenium is 46.90 mg/g. (2) Water release experiments of MNZ-Se showed that regardless of how the pH of the aqueous solution changes, the trend of the release of selenium from MNZ-Se in aqueous solution is not affected and first decreases before stabilizing. (3) Soil release experiments of MNZ-Se showed that the selenium content in the soil increased and reached the concentration in the standard of selenium-rich soil. Addition amount and soil pH value will affect the release ratio. The release ratio of MNZ-Se in the water was higher than that in the soil. (4) With an increase in the soil MNZ-Se content, the selenium content in the soil and B. c increases. Above all, MZN can be a good medium for water pollutant removal and soil improvement.

scholarly journals Removal of Phenol from Aqueous Solution Using Internal Microelectrolysis with Fe-Cu: Optimization and Application on Real Coking Wastewater

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 720
Author(s):  
Do Tra Huong ◽  
Nguyen Van Tu ◽  
Duong Thi Tu Anh ◽  
Nguyen Anh Tien ◽  
Tran Thi Kim Ngan ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Ph Value ◽  
Reaction Rate Constant ◽  
Phenol Concentration ◽  
Treated Wastewater ◽  
Coking Wastewater ◽  
X Ray ◽  
Chemical Plating ◽  
Internal Electrolysis ◽  
Phenol Decomposition

Fe-Cu materials were synthesized using the chemical plating method from Fe powder and CuSO4 5% solution and then characterized for surface morphology, composition and structure by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The as-synthesized Fe-Cu material was used for removal of phenol from aqueous solution by internal microelectrolysis. The internal electrolysis-induced phenol decomposition was then studied with respect to various parameters such as pH, time, Fe-Cu material weight, phenol concentration and shaking speed. The optimal phenol decomposition (92.7%) was achieved under the conditions of (1) a pH value of phenol solution of 3, (2) 12 h of shaking at the speed of 200 rpm, (3) Fe-Cu material weight of 10 g/L, (4) initial phenol concentration of 100.98 mg/L and (5) at room temperature (25 ± 0.5 °C). The degradation of phenol using Fe-Cu materials obeyed the second-order apparent kinetics equation with a reaction rate constant of k of 0.009 h−1L mg−1. The optimal process was then tested against real coking wastewater samples, resulting in treated wastewater with favorable water indicators. Current findings justify the use of Fe-Cu materials in practical internal electrolysis processes.

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