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1.
Buffer capacity of ultrafiltered skim milk retentates at various protein concentrations and growth of direct set, frozen concentrated lactic starter cultures in such retentates were studied. Maximum buffering occurred at approximately pH 5.1 to 5.3. An average .48% lactic acid concentration was required to reduce the pH of plain skim milk to 4.6 compared with 1.01% for skim milk retentates concentrated 2.3:1 and 1.14% for skim milk retentate concentrated 2.6:1. Skim milk retentates concentrated 4.3:1 and 5.8:1 were unable to attain pH 4.6 even when titratable acid was greater than 1.8%. Lactic acid required to reduce pH to 4.6 for the two lower concentrated retentates (2.3:1 and 2.6:1) were 1.85 and 2.45%. Time to attain pH 4.6 was a function of the bacterial cell concentration of the cultures and the total protein level of retentates. Starter organism growth was unaffected by high total solids or ash of retentates. Growth rate and lactose metabolism decreased markedly below pH 5.2 at which point bacterial population was 10(9) cfu/ml. 相似文献
2.
Manu Kumar Sang-Min Chung Ganuskh Enkhtaivan Rahul V. Patel Han-Seung Shin Bhupendra M. Mistry 《International journal of molecular sciences》2021,22(5)
In this study, we have introduced newly synthesized substituted benzothiazole based berberine derivatives that have been analyzed for their in vitro and in silico biological properties. The activity towards various kinds of influenza virus strains by employing the cytopathic effect (CPE) and sulforhodamine B (SRB) assay. Several berberine–benzothiazole derivatives (BBDs), such as BBD1, BBD3, BBD4, BBD5, BBD7, and BBD11, demonstrated interesting anti-influenza virus activity on influenza A viruses (A/PR/8/34, A/Vic/3/75) and influenza B viral (B/Lee/40, and B/Maryland/1/59) strain, respectively. Furthermore, by testing neuraminidase activity (NA) with the neuraminidase assay kit, it was identified that BBD7 has potent neuraminidase activity. The molecular docking analysis further suggests that the BBD1–BBD14 compounds’ antiviral activity may be because of interaction with residues of NA, and the same as in oseltamivir. 相似文献
3.
Studies were undertaken on the isolation and identification of reaction products of ammonium nitrate phosphate (ANP) fertilizers containing 30, 50 and 70 per cent water-soluble phosphorus (WSP) of total phosphorus in representative soils of the vertisol, oxisol, alfisol, entisol, mollisol and aridisol groups of India. ANP fertilizers were applied in solid form to soil, and reaction products formed at and around the site of ANP fertilizer placement were identified after six weeks incubation in moist soils by X-ray diffraction technique. DCPD (dicalcium phosphate dihydrate- CaHPO4 · 2H2O) was the major reaction product of ANP fertilizers containing 30 and 50 per cent WSP in vertisol, entisol, aridisol, mollisol, oxisol and alfisol, and of ANP containing 70 per cent WSP in vertisol, entisol, alfisol, aridisol and mollisol. DCP (dicalcium phosphate-CaHPO4) was detected with ANP of 30 and 50 per cent WSP in the vertisol, alfisol, entisol, mollisol and aridisol groups of soils. In addition to DCPD, FePO4 · 2H2O (metastrengite) and AlPO4 · 2H2 O-monoclinic (metavariscite) were formed in alfisol and oxisol soils with ANP of 30 and 50 per cent WSP. FePO4 · 2H2O and AlPO4 · 2H2O (metavariscite) were identified in alfisol and oxisol soils while AlPO4 · 2H2O-orthorhombic (variscite) was formed in alfisol soils with ANP of 70 per cent WSP. 相似文献
4.
Tallents G.J. Abou-Ali Y. Demir A. Dong Q. Edwards M.H. Mistry P. Pert G.J. 《IEEE journal of selected topics in quantum electronics》2004,10(6):1373-1381
Recent experimental work on the development of extreme ultraviolet lasers undertaken using as the pumping source the VULCAN laser at the Rutherford Appleton Laboratory is compared to detailed simulations. It is shown that short duration (/spl sim/picosecond) pumping can produce X-ray laser pulses of a few picosecond duration and that measurement of the emission from the plasma can give an estimate of the duration of the gain coefficient. The Ehybrid fluid and atomic physics code developed at the University of York is used to simulate X-ray laser gain and plasma emission. Two postprocessors to the Ehybrid code are utilized: 1) to raytrace the X-ray laser beam amplification and refraction and 2) to calculate the radiation emission in the kiloelectronvolt photon energy range. The raytracing and spectral simulations are compared, respectively, to measured X-ray laser output and the output of two diagnostics recording transverse X-ray emission. The pumping laser energy absorbed in the plasma is examined by comparing the simulations to experimental results. It is shown that at high pumping irradiance (>10/sup 15/ Wcm/sup -2/), fast electrons are produced by parametric processes in the preformed long scalelength plasmas. These fast electrons do not pump the population inversion and so pumping efficiency is reduced at high irradiance. 相似文献
5.
Abstract We have studied the temperature dependence of the current due to photoexcited carriers in p-i-n single quantum-well optical modulators, in order to ascertain the dominant transport mechanisms involved. A model describing the photocurrent is presented which includes the temperature and field dependence of the thermal emission, the tunnelling, the mobility and the recombination rate. A comparison between the experimental results and the model is also presented, outlining the probable transport processes. 相似文献
6.
Aristides D. Tagalakis Vignesh Jayarajan Ruhina Maeshima Kin H. Ho Farhatullah Syed Lin-Ping Wu Ahmad M. Aldossary Mustafa M. Munye Talisa Mistry Olumide Kayode Ogunbiyi Arturo Sala Joseph F. Standing Seyed M. Moghimi Andrew W. Stoker Stephen L. Hart 《Advanced functional materials》2021,31(37):2104843
7.
The Synthesis and Biological Evaluation of Multifunctionalised Derivatives of Noscapine as Cytotoxic Agents 下载免费PDF全文
Aaron J. DeBono Dr. Sarah J. Mistry Jinhan Xie Divya Muthiah Jackson Phillips Dr. Sabatino Ventura Dr. Richard Callaghan Prof. Colin W. Pouton Dr. Ben Capuano Prof. Peter J. Scammells 《ChemMedChem》2014,9(2):399-410
Noscapine, a phthalideisoquinoline alkaloid derived from Papaver somniferum, is a well‐known antitussive drug that has a relatively safe in vitro toxicity profile. Noscapine is also known to possess weak anticancer efficacy, and since its discovery, efforts have been made to design derivatives with improved potency. Herein, the synthesis of a series of noscapine analogues, which have been modified in the 6′, 9′, 1 and 7‐positions, is described. In a previous study, replacement of the naturally occurring N‐methyl group in the 6′‐position with an N‐ethylaminocarbonyl was shown to promote cell‐cycle arrest and cytotoxicity against three cancer cell lines. Here, this modification has been combined with other structural changes that have previously been shown to improve anticancer activity, namely halo substitution in the 9′‐position, regioselective O‐demethylation to reveal a free phenol in the 7‐position, and reduction of the lactone to the corresponding cyclic ether in the 1‐position. The incorporation of new aryl substituents in the 9′‐position was also investigated. The study identified interesting new compounds able to induce G2/M cell‐cycle arrest and that possess cytotoxic activity against the human prostate carcinoma cell line PC3, the human breast adenocarcinoma cell line MCF‐7, and the human pancreatic epithelioid carcinoma cell line PANC‐1. In particular, the ethyl urea cyclic ether noscapinoids and a compound containing a 6′‐ethylaminocarbonyl along with 9′‐chloro, 7‐hydroxy and lactone moieties exhibited the most promising biological activities, with EC50 values in the low micromolar range against all three cancer cell lines, and these derivatives warrant further investigation. 相似文献
8.
The applicability of palladium for the separation of hydrogen isotopes (hydrogen and deuterium) is evaluated systematically by generating isotherm data and conducting column experiments in a laboratory set-up. Effect of various parameters such as concentration of the isotopic mixture, particle size, eluent flow rate, etc. is studied experimentally. A fixed-bed chromatographic model is developed and validated using the experimental data. The model is further used to predict the performance of a multi-column configuration for large-scale separation. Chromatographic separation is thus found to be a promising technique to achieve the required purity and hence it may be clubbed with the existing systems (e.g. cryogenic distillation) to obtain enhanced performance. 相似文献
9.
The alkali steeping process was tested for extraction of starch from degerminated yellow corn flour. The effect of three process parameters, alkali concentration (0.1 and 0.4%), steep temperature (25 and 55°C) and steep time (30 and 90min) were evaluated for their effect on yield, protein and sodium contents of starch. Two-level full factorial design was used to investigate the process. The experimental results indicated that starch yield increased with increasing steep temperature and at low alkali concentration. All main effects and interactions were found to have significant effect on protein content in the extracted starch. The sodium content of the starch was effected by the three main effects and the three two-factor interaction effects. Conditions were identified that simultaneously produced a high starch yield, low protein and sodium contents were 0.1% alkali steep at 55°C for 30 min. 相似文献
10.
Determining torque and current at locked rotor and various slips during the acceleration test on a synchronous machine is very tedious and time consuming. Induction and synchronous machines behave similarly during acceleration except that synchronous machine acceleration can include a pulsation torque. Because of the salient poles, conditions exist where the synchronous motor has minimum torque at quadrature axis and maximum torque at direct axis during locked rotor or stall. Since synchronous machines do not have large numbers of rotor bars in the amortisseur winding, like the induction motor has in the squirrel cage, their stall times tend to be shorter. Due to the shorter stall time and large starting torque, locked-rotor torque and current are generally determined from acceleration tests conducted at reduced voltage rather than by tests at stand-still. Data showing that saturation effects impact both torque and current are presented in this paper. The data shows that the voltage index that has to be applied to the torque and current measured at reduced voltage varies with speed and can be obtained from a series of acceleration tests 相似文献