Effect of organic additives on activity of PdCl2, in synthesis of phenyl isocyanate by carbonylation of nitrobenzene

Author(s):  
B. K. Nefedov ◽  
V. I. Manov-Yuvenskii
2016 ◽  
Vol 15 (5) ◽  
pp. 1041-1048
Author(s):  
Irina Smical ◽  
Adriana Muntean ◽  
Valer Micle
Keyword(s):  

2007 ◽  
Vol 2 (1) ◽  
Author(s):  
D.A. Danilovich ◽  
M.N. Kozlov ◽  
V.I. Sklyar ◽  
Yu.A. Nikolaev ◽  
N.M. Shchegolkova ◽  
...  

This work demonstrates a possibility of composting of municipal waste waters sludge (WWS) digested during 5-7 days, of the Kuryanovo waste water treatment plants (the city of Moscow) without the use of traditional organic additives – sawdust, peat, thatch. As a recycling filler (repeatedly used), enhancing the porosity of the composted mixture, ribbed polyethylene spheres (∅=8 cm) and wood chips (having dimension of 5-10 cm) were used. Composting was performed efficiently in both cases, however, the use of wood ships had technological and economical advantages. The process of composting was carried out during 2-4 weeks and was composed of classical phases of active heating (a rate of 0.2-0.3oC/h was obtained), maintaining of maximum temperature during 1-2 days, and cooling down to the ambient temperature. During the course of composting, a product was obtained, having attractive organoleptic properties, suitable for application in municipal laying-out of greenery.


2020 ◽  
Vol 17 (7) ◽  
pp. 525-534 ◽  
Author(s):  
Nevin Arıkan Ölmez ◽  
Faryal Waseer

Background: Urea, thiourea, and 1,2,4-oxadiazole compounds are of great interest due to their different activities such as anti-inflammatory, antiviral, analgesic, fungicidal, herbicidal, diuretic, antihelminthic and antitumor along with antimicrobial activities. Objective: In this work, we provide a new series of potential biologically active compounds containing both 1,2,4-oxadiazole and urea/thiouprea moiety. Materials and Methods: Firstly, 5-chloromethyl-3-aryl-1,2,4-oxadiazoles (3a-j) were synthesized from the reaction of different substituted amidoximes (2a-j) and chloroacetyl chloride in the presence of pyridine by conventional and microwave-assisted methods. In the conventional method, 1,2,4-oxadiazoles were obtained in two steps. O-acylamidoximes obtained in the first step at room temperature were heated in toluene for an average of one hour to obtain 1,2,4-oxadiazoles. The yields varied from 70 to 96 %. 1,2,4-oxadiazoles were obtained under microwave irradiation in a single step in a 90-98 % yield at 160 °C in five minutes. 5-aminomethyl-3-aryl-1,2,4- oxadiazoles (5a-j) were obtained by Gabriel amine synthesis in two steps from corresponding 5-chloromethyl-3- aryl-1,2,4-oxadiazoles. Finally, twenty new urea (6a-j) and thiourea (7a-j) compounds bearing oxadiazole ring were synthesized by reacting 5-aminomethyl-3-aryl-1,2,4-oxadiazoles with phenyl isocyanate and isothiocyanate in tetrahydrofuran (THF) at room temperature with average yields (40-70%). Results and Discussions: An efficient and rapid method for the synthesis of 1,2,4-oxadiazoles from the reaction of amidoximes and acyl halides without using any coupling reagent under microwave irradiation has been developed, and twenty new urea/thiourea compounds bearing 1,2,4-oxadiazole ring have been synthesized and characterized. Conclusion: We have synthesized a new series of urea/thiourea derivatives bearing 1,2,4-oxadiazole ring. Also facile synthesis of 3,5-disubstituted 1,2,4-oxadiazoles from amidoximes and acyl chlorides under microwave irradiation was reported. The compounds were characterized using FTIR, 1H NMR, 13C NMR, and elemental analysis techniques.


Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 890
Author(s):  
Mateusz Barczewski ◽  
Olga Mysiukiewicz ◽  
Aleksander Hejna ◽  
Radosław Biskup ◽  
Joanna Szulc ◽  
...  

In this work, thermally expanded vermiculite (TE-VMT) was surface modified and used as a filler for composites with a polylactide (PLA) matrix. Modification of vermiculite was realized by simultaneous ball milling with the presence of two PLA chain extenders, aromatic carbodiimide (KI), and 4,4’-methylenebis(phenyl isocyanate) (MDI). In addition to analyzing the particle size of the filler subjected to processing, the efficiency of mechanochemical modification was evaluated by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The composites of PLA with three vermiculite types were prepared by melt mixing and subjected to mechanical, thermomechanical, thermal, and structural evaluation. The structure of composites containing a constant amount of the filler (20 wt%) was assessed using FTIR spectroscopy and SEM analysis supplemented by evaluating the final injection-molded samples’ physicochemical properties. Mechanical behavior of the composites was assessed by static tensile test and impact strength hardness measurements. Heat deflection temperature (HDT) test and dynamic thermomechanical analysis (DMTA) were applied to evaluate the influence of the filler addition and its functionalization on thermomechanical properties of PLA-based composites. Thermal properties were assessed by differential scanning calorimetry (DSC), pyrolysis combustion flow calorimetry (PCFC), and thermogravimetric analysis (TGA). The use of filler-reactive chain extenders (CE) made it possible to change the vermiculite structure and obtain an improvement in interfacial adhesion and more favorable filler dispersions in the matrix. This translated into an improvement in impact strength and an increase in thermo-mechanical stability and heat release capacity of composites containing modified vermiculites.


2021 ◽  
Vol 35 (5) ◽  
pp. 4616-4616
Author(s):  
Florian Wesenauer ◽  
Christian Jordan ◽  
Mario Pichler ◽  
Aron Frei ◽  
Mudassar Azam ◽  
...  

BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Masresha Mamo ◽  
Henok Kassa ◽  
Lalit Ingale ◽  
Stefaan Dondeyne

Abstract Background The present study evaluated the compost quality from municipal solid waste (MSW) and organic additives of coffee by-products and leaf of Millettia ferruginea. Compost sample (n = 30) was taken from fresh compost materials and MSW and different organic additive treatments (T1, T2, T3, T4, and T5). Compost treatments phytotoxicity test was conducted using lettuce seed (Lactuca Sativa L. var. crispa). Analysis of variance (ANOVA) was performed using SPSS (version 22) on major compost quality characteristics. Results The compost Physico-chemical characteristics like temperature (26.4 °C), moisture content (45.5%), electrical conductivity (4.6 mS/cm), pH (7.9), total nitrogen (1.2%) and phosphorous content (2918 ppm) in T4 and T5 were analogous but both are significantly different from T3, T2 and T1 compost treatments. Phytotoxicity test using 100% compost treatment media showed that T4 (101%) and T5 (102%) are phytonutrient for lettuce plant. While, T3 and T2; and T1 compost treatments are non-phytotoxic and moderately phytotoxic respectively to lettuce plant. Conclusion Therefore, compost from MSW + M. ferruginea (T4) and MSW + coffee pulp + M. ferruginea (T5) are important for improving the physico-chemical characteristics of compost and are phytonutrient for lettuce plant. Thus, for effectively management of the 75% of organic fraction of waste generated from households in the study area, recycling methods like composting with organic additives must be used at large.


2020 ◽  
Vol 18 (1) ◽  
pp. 951-961
Author(s):  
Qiuju Chen ◽  
Tao Hui ◽  
Hongjuan Sun ◽  
Tongjiang Peng ◽  
Wenjin Ding

AbstractVarious morphologies of magnesium carbonate hydrate had been synthesized without using any organic additives by carefully adjusting the reaction temperature and time during the talc carbonation process. At lower temperatures, magnesium carbonate hydrate was prone to display needle-like morphology. With the further increase of the carbonation temperature, the sheet-like crystallites became the preferred morphology, and at higher aging temperatures, these crystallites tended to assemble into layer-like structures with diverse morphologies, such as rose-like particles and nest-like structure. The reaction time had no effect on the crystal morphology, but it affected the particle size and situation of the crystal growth. X-Ray diffraction results showed that these various morphologies were closely related to their crystal structure and compositions. The needle-like magnesium carbonate hydrate had a formula of MgCO3·3H2O, whereas with the morphological transformation from needle-like to sheet-like, rose-like, and nest-like structure, their corresponding compositions also changed from MgCO3·3H2O to 4MgCO3·Mg(OH)2·8H2O, 4MgCO3·Mg(OH)2·5H2O, and 4MgCO3·Mg(OH)2·4H2O.


Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 773
Author(s):  
Jyun-Yan Ye ◽  
Kuo-Fu Peng ◽  
Yu-Ning Zhang ◽  
Szu-Yuan Huang ◽  
Mong Liang

A series of N-substituted polyether-block-amide (PEBA-X%) copolymers were prepared by melt polycondensation of nylon-6 prepolymer and polytetramethylene ether glycol at an elevated temperature using titanium isopropoxide as a catalyst. The structure, thermal properties, and crystallinity of PEBA-X% were investigated using nuclear magnetic resonance spectroscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, wide angle X-ray diffraction, and thermogravimetric analysis. In general, the crystallinity, melting point, and thermal degradation temperature of PEBA-X% decreased as the incorporation of N-methyl functionalized groups increased, owing to the disruption caused to the structural regularity of the copolymer. However, in N-acetyl functionalized analogues, the crystallinity first dropped and then increased because of a new γ form arrangement that developed in the microstructure. After the cross-linking reaction of the N-methyl-substituted derivative, which has electron-donating characteristics, with poly(4,4′-methylenebis(phenyl isocyanate), the decomposition temperature of the resulting polymer significantly increased, whereas no such improvements could be observed in the case of the electro-withdrawing N-acetyl-substituted derivative, because of the incompleteness of its cross-linking reaction.


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