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In this work, a series of hydroxymethyl tetramide (HMTEA) was synthesized from vegetable oil, triacetylenetetramine and hexamethylenetetramine, which was evaluated as viscosity reducer and pour point depressor for crude oil. The results showed that HMTE has a good viscosity reduction effect on the crude oil from Yanchang Oilfield, with the highest viscosity reduction rate of 93%. The highest pour point reduction depression was achieved as 6.5℃. Differential scanning calorimetry and paraffin crystal morphology characterization were conducted on the crude oil to elucidate the mechanism of viscos..read more
Xuefan Gu, Peng Wang, Zhen Guo, Weichao Du, Sanbao Dong..
- 26 Aug 2020
- Volume Detail: VOLUME 42, NO4, AUG-2020
- Pages: 488
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Over-stabilized foam has always been a problem that plagues the dodecylamine (DDA) flotation system. In this study, a new device, “automatic foam analyzer”, was successfully used to characterize the behavior of foam in DDA solution. The effects of pH and DDA dosage on the foam properties were investigated from four aspects: bubble diffusion capacity, Bikerman coefficient, half-life period and solution conductivity, and the mechanism of pH and DDA concentration on foam properties was analyzed by solution chemistry and surface tension of DDA, then the change process of foam structure was deduced..read more
Weimin Xie, Dongsheng He, Shuang Liu, Fei Chen, Hongqia..
- 26 Aug 2020
- Volume Detail: VOLUME 42, NO4, AUG-2020
- Pages: 495
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Catalytic oxidation of organic volatile compounds (VOCs) is considered superior to conventional methods because very low concentration of VOCs can also be oxidized and removed at low temperatures without consumption of addditional fuel and introduction of NOx compounds into the environment. Herein, the synthesis of MnO2 nanoparticles on bentonite (Bent) support in the presence of CuO for catalytic oxidation of m-xylene is reported. The synthesized materials were analyzed with FT-IR, XRD, and TEM analysis for structural and morphological characterization. XRD and TEM analysis indicated the form..read more
Mo Thi Nguyen, Cam Minh Le, Tuan Minh Nguyen, Hao Hoang..
- 26 Aug 2020
- Volume Detail: VOLUME 42, NO4, AUG-2020
- Pages: 504
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The continuing research for the determination of bioactive secondary metabolites from Turkish geophytes as therapeutic agents for dementia is mainly based on the need for drug candidates affected to brain areas. In this study, the in vitro anticholinesterase activity of the alkaloidal fractions of the tubers of Corydalis triternata Zucc. was investigated for their neuroprotective potential. Furthermore, the content of the active alkaloid fractions of the tubers was determined by LC-Q-TOF-MS. The tubers of Corydalis triternata Zucc. were collected from Hatay province of Turkey. The plant specie..read more
Mehtap Kılıc, Erdal Kaya, Ayhan Ibrahim Aysal, Bilge Se..
- 26 Aug 2020
- Volume Detail: VOLUME 42, NO4, AUG-2020
- Pages: 515
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In this work, a simple and rapid spectrophotometric method, which is based on the fact that Iron(Ⅱ) -gluconic acid complex as a kind of reducing agent deterioration of indigo carmine dyes, was developed to detect gluconic acid in food. Under the optimal experimental condition, a linear range of 3.6 M to 900 M was obtained for gluconic acid with a limit of detection of 1.1 μM. The colorimetric method was rapid and robust with a low cost and can be applied to gluconic acid detection in food samples...read more
Yifeng Lan, Lixiang Zuo, Yangyang Zhou, Yanli Wei and C..
- 26 Aug 2020
- Volume Detail: VOLUME 42, NO4, AUG-2020
- Pages: 525
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Current research focuses on synthesis and characterization of magnetically separable core@shell (NiFe2O4@TiO2) nanostructured photocatalyst with different weight percent (10, 20, 30, and 40) TiO2 using simple wet chemical techniques. Magnetic core with TiO2 shell was synthesized by the hydrolysis of TTIP precursor with NiFe2O4 nanoparticles. NiFe2O4 nanoparticles were synthesized by the sol-gel auto combustion method. The synthesized nanostructures were characterized for structural, morphological and magnetic behavior using XRD, TEM, SEM and VSM while the surface area was calculated using Brun..read more
Mutawara Mahmood Baig, Erum Pervaiz, Muhammad Junaid Af..
- 26 Aug 2020
- Volume Detail: VOLUME 42, NO4, AUG-2020
- Pages: 531
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A novel and simple cloud point extraction (CPE) method for detecting trace silver has been built up with flame atomic absorption spectrometry (FAAS) through adding proper amount of n-octanol into Triton X-100 resulting in an obvious decrease of the cloud point. In the method, rhodanine was chosen as chelating agent for the preconcentration of silver. The influence of major experimental parameters such as pH, chelating agent concentration, surfactant concentration, equilibration temperature and time on the extraction of silver from aqueous solutions was investigated and optimized. Under the opt..read more
Juncui Xu, Fazhi Xie, Xianming Yue, Zhengyu Li, Shixion..
- 26 Aug 2020
- Volume Detail: VOLUME 42, NO4, AUG-2020
- Pages: 542
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A purified raw montmorillonite and hydroxy-aluminum pillared montmorillonite have been prepared from a natural bentonite from Maghnia, Algeria. These materials have been analyzed by X-ray fluorescence spectroscopy, X-ray diffraction, Infrared spectroscopy and nitrogen adsorption-desorption measurement. The pillared montmorillonite provided a certain increase of interlayer basal spacing and BET surface area and consequently the improvement of its capacities adsorption and decolorization of Methylene Blue. The adsorption properties of these materials were studied as a function of contact time, s..read more
Houria Rezala, Houda Douba, Horiya Boukhatem and Amaya ..
- 26 Aug 2020
- Volume Detail: VOLUME 42, NO4, AUG-2020
- Pages: 550
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A series of novel 4-phenylaminobenzofuro[2,3-d]pyrimidine derivatives had been prepared and assessed for their in vitro antiproliferative activities against three lung cancer cell lines (A549, H460 and H1975). The bioassay results showed most of the designed compounds exhibited potential antiproliferation activities. Among them, compound 8f exhibited remarkable inhibitory activity against A549 and H460 cell lines with IC50 value of 2.54 μM and 2.68 μM, respectively, which was comparable to that of the positive control sorafenib (IC50 = 2.69 μM for A549 and 3.71 μM for H460). AO/EB staining sug..read more
Ju liu, Jun Li, Jian-tao Shi, Jie Li, Xue-chen Hao, Dua..
- 26 Aug 2020
- Volume Detail: VOLUME 42, NO4, AUG-2020
- Pages: 564
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The new nitroisofalvones 2a-k were synthesized via nitration of the corresponding isoflavones 1a-f using NH4NO3/TFAA in acetonitrile. The aminoisoflavones 3a-g, also new, were produced by selective reduction of the corresponding nitroisoflavones with SnCl2.2H2O. The nitro- and aminoisoflavones, tested in vitro concerning their effects on the proliferation of endothelial cells showed modest activities. All the new products are fully characterized and the nitro compounds analyzed thoroughly by NMR to allow complete assignment of the proton and carbon resonance and to establish the orientation of..read more
Nawaf Al-Maharik, Nidal Jaradat, Adel Hidmi..
- 26 Aug 2020
- Volume Detail: VOLUME 42, NO4, AUG-2020
- Pages: 572
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