Determination of power-time curves of bacterial growth and study of optimum growth temperature and acidity

Bacterial growth power-time curves were determined by using the 2277 Thermal Activity Monitor. The growth rate constants at different temperatures and acidities were calculated via the optimum growth temperature and optimum growth acidity obtained.     

Kinetics of growth from pre-existing surface nuclei

Summary Isothermal and non-isothermal kinetics of three dimensional growth processes from nuclei pre-existing on surface of infinite plate specimen have been derived. Some useful and interesting relations have been found, and methods for kinetic analysis of experimental data are proposed.     

Coordination polyhedron growth mechanism model and growth habit of crystals

A new growth mechanism model, coordination polyhedron growth mechanism model, is introduced from the angle of the coordination of anion and cation to each other at the interface. It is pointed out that the force driving the growth unit to enter the crystal lattice is the electrostatic attraction force between ions, whose relative size can be approximately measured by the electrostatic bond strength (EBS) that reaches a nearest neighbor anion (or cation) in the parent phase from a cation (or anion) at the interface. The growth habits of NaCI, ZnS, CaF2 and Csl crystals are discussed, and a new growth habit rule is proposed as follows. When the growth rate of a crystal is determined by the step generation rate, the growth habit of this crystal is related to the coordination number of the ion with the smallest coordination rate at the interface of various crystal faces. The smaller the coordination number of the ion at the interface, the faster the growth rate of corresponding crystal face. When the growth     

混合稀土对作物生长量的影响

用欧洲经济合作发展组织(OECD)提出的方法,在3种土壤（红壤、黄潮土、黄褐土）上进行了混合稀土（浓度0～5.0g     

A growing 2D spherulite and calculus of variations Part I: A 2D spherulite in a linear field of growth rate

We propose to take the calculus of variations in order to compute the shape of a growing 2D spherulite in an uniaxial field of growth rate. We are concerned with the growth line (a path that is traveled in the shortest possible time from nucleus to a point (x₁, y₁), where a molecule just crystallizes) and the growth front (the times between spherulite and supercooled material). The Euler differential equation—a result of the calculus of variations—is derived for all uniaxial growth ratesv (x). Here we especially investigatev(x)=px+q.     

Onset of Chiral Adenine Surface Growth

The structure and stability of adenine crystals and thin layers has been studied by using scanning tunneling microscopy, X‐ray diffraction, and density functional theory calculations. We have found that adenine crystals can be grown in two phases that are energetically quasi‐degenerate, the structure of which can be described as a pile‐up of 2D adenine planes. In each plane, the structure can be described as an aggregation of adenine dimers. Under certain conditions, kinetic effects can favor the growth of the less stable phase. These results have been used to understand the growth of adenine thin films on gold under ultra‐high vacuum conditions. We have found that the grown phase corresponds to the α‐phase, which is composed of stacked prochiral planes. In this way, the adenine nanocrystals exhibit a surface that is enantiopure. These results could open new insight into the applications of adenine in biological, medical, and enantioselective or pharmaceutical fields.     

Growth kinetics and diosgenin estimation from callus cultures of Costus speciosus (Koen. ex. Retz.)

The present investigation reports the growth kinetics and diosgenin accumulation in callus cultures of Costus speciosus. Effect of explants, media and plant growth regulators was evaluated with respect to callus induction and growth. Out of the two explants viz pseudostem and seed, pseudostem showed maximum callus induction frequency of 90% on MS medium. The fresh weight of callus was maximum (9-folds) on 28th day on 1.0 mg/L picloram containing medium. The callus obtained was white compact hard (WCH). For growth kinetics study pseudostem derived callus was transferred on different media supplemented with 1.0 mg/L picloram. All phases of growth were seen in callus inoculated on all the three media except the absence of stationary phase on MS and SH media. MS medium proved to be the best for maximum biomass accumulation (9-fold) on 28th day of culture and callus in post-exponential phase showed maximum diosgenin accumulation (33 ppm).     

Fabrication of extracellular matrix-coated conductive polypyrrole-poly(l-lactide) fiber-films and their synergistic effect with (nerve growth factor)/(epidermal growth factor) on neurites growth

Non-nerve cell-derived extracellular matrix (ECM) was coated on the aligned porous polypyrrole-poly(l-lactide) (PPy-PLLA) fiber-films with the conductivity of ∼12 mS/m via L929 cells culture and lysing, resulting in ∼10% increase of PC12 cells attachment and ∼26 μm increase of neurites length. The neurite length of ∼149 μm in EGF/NGF group (optimal concentration radio of 12.5/50 (ng/mL)) on aligned and ECM-conjugated fiber-films was significantly larger than ∼94 μm in only NGF group (50 ng/mL), confirming the synergy of EGF, NGF and aligned ECM-conjuaged PPy-PLLA fibers. When differentiated PC12 cells were exerted electrical stimulation (ES) of 100 mV/cm for 4 h/day in 2 day through ECM-PPy-PLLA fiber-films, their neurite length reached to ∼251 μm, significantly larger than ∼149 μm of group without ES, due to the higer expression of related neural proteins in ES group. A simple mechanism was proposed to analyze synergistical effect of ECM, EGF, NGF on axons adhesion and elongation along the aligned ECM-coated fibers under ES condition.     

Crystal growth and structure of three new neodymium containing silicates: Na0.50Nd4.50(SiO4)3O,Na0.63Nd4.37(SiO4)3O0.74F0.26 and Na4.74Nd4.26(O0.52F0.48)[SiO4]4

Single crystals of Na_0.50Nd_4.50(SiO₄)₃O, Na_0.63Nd_4.37(SiO₄)₃O_0.74F_0.26, and Na_4.74Nd_4.26(O_0.52F_0.48)[SiO₄]₄ were synthesized via flux growth using a NaF/KF eutectic flux and the crystal structure was determined by single crystal X-ray diffraction. Na_0.50Nd_4.50(SiO₄)₃O and Na_0.63Nd_4.37(SiO₄)₃O_0.74F_0.26 adopt the apatite structure and crystallize in the hexagonal space group P6₃/m, while Na_4.74Nd_4.26(O_0.52F_0.48)[SiO₄]₄ crystallizes in the tetragonal space group I-4 and exhibits rare-earth mixing on the sodium site. The unit cells of the crystals are a = 9.5400(3) Å and c = 7.0331(5) Å for Na_0.50Nd_4.50(SiO₄)₃O, a = 9.5533(3) Å and c = 7.0510(4) Å for Na_0.63Nd_4.37(SiO₄)₃O_0.74F_0.26, and a = 12.1255(3) Å and c = 5.4656(2) Å for Na_4.74Nd_4.26(O_0.52F_0.48)[SiO₄]₄. These three compounds exhibit three-dimensional crystal structures that are discussed in detail in this paper.     

微量热法测定细菌的最低生长温度

微量热法测定细菌的最低生长温度南照东，刘永军，孙海涛，张洪林（曲阜师范大学化学系曲阜２７３１６５）关键词微量热法，细菌的生长热谱，最低生长温度，生长速率常数我们应用微量热法测定了大肠杆菌（Ｅ．ｃｏｌｉ），白色葡萄球菌（Ｓ．ａｌｂｕｓ），金黄色葡萄球菌...     

气体水合物膜生长动力学研究进展

由于大多数水合物客体不溶于水,水相与客体相界面首先形成一层气体水合物膜,气体水合物膜生长是水合物生长的主要形式,研究水合物膜生长规律对于理解水合物生长动力学及进一步开发促进和抑制水合物生长的应用技术具有重要意义.本文综述了近年来气体水合物膜生长形态、横向生长和增厚生长的理论和实验研究进展.首先介绍了不同客体-水体系(包括气/液界面、液/液界面和气-液-液体系)形成的水合物膜生长形态随实验条件的变化规律,然后分别从横向生长和增厚生长两方面总结了水合物膜生长的实验和模型方面的研究工作,阐述了常见的膜生长速率和膜厚度的测量方法,分析了水合物膜生长的传热和传质机理.同时展望了未来水合物膜生长研究的发展方向.     

Nucleation and Growth of CeF3 and NaCeF4 Nanocrystals

Studying growth : The diffusion‐controlled kinetic (DCK) model and the surface chemical thermodynamics (SCT) model have been successfully applied to interpret the nucleation and growth mechanism of CeF₃ (see TEM images) and NaCeF₄ nanocrystals, and may generally give light to the size‐control and morphology prediction of rare‐earth fluorides at the nanoscale level.

     

A Bioorthogonal Approach for the Preparation of a Titanium‐Binding Insulin‐like Growth‐Factor‐1 Derivative by Using Tyrosinase

The generation of metal surfaces with biological properties, such as cell‐growth‐enhancing and differentiation‐inducing abilities, could be potentially exciting for the development of functional materials for use in humans, including artificial dental implants and joint replacements. However, currently the immobilization of proteins on the surfaces of the metals are limited. In this study, we have used a mussel‐inspired bioorthogonal approach to design a 3,4‐hydroxyphenalyalanine‐containing recombinant insulin‐like growth‐factor‐1 using a combination of recombinant DNA technology and tyrosinase treatment for the surface modification of titanium. The modified growth factor prepared in this study exhibited strong binding affinity to titanium, and significantly enhanced the growth of NIH3T3 cells on the surface of titanium.     

Location‐Controlled Growth of Vertically Aligned Si Nanowires using Au Nanodisks Patterned by KrF Stepper Lithography

The location‐controlled epitaxial growth of vertically aligned Si nanowire (v‐SiNW) arrays over large surface area was investigated with Au nanodisks (AuNDs) patterned by KrF stepper lithography. There are two steps for synthesizing v‐SiNWs from an AuND pattern: annealing and growth. The annealing process induces the formation of a single Au nanoparticle (AuNP) from an AuND pattern, which consists of several cracked AuNPs. Here, the oxide layer between the AuNDs and Si substrate is necessary for impeding the diffusion of Si atoms into the AuNPs. However, the oxide layer must be removed for properly aligned epitaxial SiNW growth. These SiNW arrays in large area can contribute highly to improve a nanowire‐based engineering by controlling the location of SiNWs with consistent pitch.     

The Kinetics of Crystal Growth

The fundamentals of the theory of crystal growth comprise the two concepts of growth via two-dimensional nuclei and growth with the aid of dislocations. Measurements of the relationship between rate of growth and supersaturation are particularly suitable for testing theoretical predictions. Experimental results are compared with predictions for crystal growth from the vapor phase, from solution, and from the melt. Depending on the experimental conditions, examples of both types of growth are met irrespective of the nature of the mother phase.     

Control and Design Principles in Biological Mineralization

The control of crystal formation has been developed to a remarkable degree by many organisms. Oriented nucleation, control over crystal morphology, formation of unique composites of proteins and single crystals, and the production of ordered multicrystal arrays, are all well within the realm of biological capability. Understanding the control and design principles in biomineralization is a fascinating subject that may well contribute to the improved fabrication of synthetic materials on the one hand, and to the solution of many serious pathological problems involving mineralization, on the other.