Structure and Properties of Concrete for Injection with Two-Stage Expansion

2017 ◽  
Vol 265 ◽  
pp. 103-108 ◽  
Author(s):  
Y.I. Koryanova
Keyword(s):  
Cement Stone ◽  
Structure And Properties ◽  
Operational Control ◽  
Two Stage ◽  
Second Stage ◽  
Mix Proportion ◽  
Kinetics Of ◽  
Technology Structure ◽  
Structure Properties

Often, when it is necessary to fill formwork space in confined working conditions with limited operational control in some engineering solutions the special materials for injection are used. In this case, it is advisable to use high-fluidity concrete mixes made with К-cement, regulator of the kinetics of structure formation, superplasticizer and gas-forming admixture. The gas-forming admixture obtains of expansion of fresh-concrete during first stage. The special sulfo-alumina additive in K-cement obtains of expansion of hardening concrete during second stage. The main regularities in the formation of the structure and properties of cement stone are considered. The dependences "composition-technology-structure-properties" for concretes with two-stage expansion are clarified. The main provisions for determination of mix proportion for concrete are proposed. The quantitative relationships between the construction properties of concretes and prescription and technological factors are obtained.

scholarly journals Modeling of structuring processes at hardening of expanding cements and concretes on their basis

2018 ◽  
Vol 196 ◽  
pp. 04035 ◽  
Author(s):  
Igor Kharchenko ◽  
Alexander Panchenko ◽  
Alexey Kharchenko ◽  
Vyacheslav Alekseev
Keyword(s):  
Theoretical Analysis ◽  
Rheological Model ◽  
Experimental Studies ◽  
High Strength ◽  
Cementitious Materials ◽  
Cement Stone ◽  
Formation Processes ◽  
Structure And Properties ◽  
Potential Index ◽  
Kinetics Of

This paper reports the results of experimental research of the effect of strain-restriction conditions on the structure and properties of sulfoaluminate expanding cementitious materials. Theoretical analysis of the development of pattern formation processes is performed by applying the developed rheological model, illustrating features of the kinetics of structure-forming processes according to the ratio of the potential index of extension with linear, flat and volumetric limitation of deformations of the extension. The results show that rheological model adequately correlates with the results of experimental studies and can be described mathematically. Found that with the volume limitation of deformations arising when mixing crystallographic phases with high density and strength, the pore structure of the cement stone contains mainly gel pores. This is the main prerequisite for obtaining a dense, high-strength and durable structure of cement stone and concrete on its basis.

Two-Stage Algorithm for Rapid Determination of the Bending Sequence in Sheet Metal Products

1996 ◽  
Author(s):  
B. Radin ◽  
M. Shpitalni ◽  
I. Hartman
Keyword(s):  
Sheet Metal ◽  
Rapid Determination ◽  
Low Cost ◽  
Combinatorial Problem ◽  
Two Stage ◽  
Practical Applications ◽  
Second Stage ◽  
Bending Sequence ◽  
Time Limitations

Abstract This paper presents an algorithm for solving the complex and critical problem of bending sequence in sheet metal manufacturing. Finding the bending sequence and required tool assignment presents a large combinatorial problem which is impossible to solve optimally for practical applications within a reasonable period of time. The paper presents a two-stage algorithm. The first stage finds a feasible solution based upon collision avoidance heuristics. The second stage rapidly seeks an alternative feasible sequence with a lower cost without exceeding time limitations. The algorithm is very practical because it reaches a low-cost solution quickly within computer memory limitations. In this paper, the problem is defined, the approach is presented formally, and finally, the power of the algorithm is demonstrated by solving bending sequences for real products.

Two-Stage Algorithm for Determination of the Bending Sequence in Sheet Metal Products

1997 ◽  
Vol 119 (2) ◽  
pp. 259-266 ◽  
Author(s):  
B. Radin ◽  
M. Shpitalni ◽  
I. Hartman
Keyword(s):  
Sheet Metal ◽  
Low Cost ◽  
Combinatorial Problem ◽  
Two Stage ◽  
Practical Applications ◽  
Second Stage ◽  
Metal Products ◽  
Bending Sequence ◽  
Time Limitations

This paper presents an algorithm for solving the complex and critical problem of bending sequence in sheet metal manufacturing. Finding the bending sequence and required tool assignment presents a large combinatorial problem which is impossible to solve optimally for practical applications within a reasonable period of time. The paper presents a two-stage algorithm. The first stage finds a feasible solution based upon collision avoidance heuristics. The second stage rapidly seeks an alternative feasible sequence with a lower cost without exceeding time limitations. The algorithm is very practical because it reaches a low-cost solution quickly within computer memory limitations. In this paper, the problem is defined, the approach is presented formally, and finally, the power of the algorithm is demonstrated by solving bending sequences for real products.

Effect of second-stage schedules of two-stage aging on the structure and properties of alloy V96Ts1

1985 ◽  
Vol 27 (7) ◽  
pp. 501-505
Author(s):  
I. N. Fridlyander ◽  
O. A. Noskova ◽  
V. I. Silaeva ◽  
T. V. Solov'eva ◽  
A. N. Ershov
Keyword(s):  
Structure And Properties ◽  
Two Stage ◽  
Second Stage

scholarly journals How contractual terms determine fiduciary duties: a two-stage process

2019 ◽  
Vol 70 (2) ◽  
pp. 242-262
Author(s):  
David Gibbs-Kneller ◽  
Derek Whayman
Keyword(s):  
Fiduciary Duty ◽  
Single Factor ◽  
Two Stage ◽  
Fiduciary Duties ◽  
Second Stage ◽  
Stage Process ◽  
Duty Of Loyalty ◽  
Two Stages

The determination of the scope of the fiduciary duty of loyalty, when created by contract, is not a unitary process. It is raised following a multi-factorial enquiry, which considers the nature of the engagement, in a first stage. Here, no single factor is conclusive. It is then, in a separate, second stage, reduced by qualifying contractual terms, which are applied almost strictly logically. This second stage uses the contractual doctrines of interpretation and implication. However, since it is a form of the fiduciary doctrine of authorisation, those contractual doctrines are modified according to fiduciary principles. We argue this follows from the underlying nature of the fiduciary obligation as a way of resolving its internal tensions. While this division has not yet been fully recognised in the cases, the courts have been inching towards it. However, not fully recognising this inevitable division and eliding the two stages has led to defective reasoning and outcomes.

scholarly journals Determination of optimum gear ratios of a two-stage helical gearbox with second stage double gear sets

2019 ◽  
Vol 635 ◽  
pp. 012012
Author(s):  
Vu Ngoc Pi ◽  
Nguyen Thi Hong Cam ◽  
Tran Thi Hong ◽  
Le Xuan Hung ◽  
Luu Anh Tung ◽  
...  
Keyword(s):  
Two Stage ◽  
Second Stage

scholarly journals Studies of precipitation during the decomposition process of phosphorus-containing compounds

2019 ◽  
Vol 80 (4) ◽  
pp. 312-315
Author(s):  
M. M. Ganbarov ◽  
M. M. Ataev ◽  
K. K. Gazvini
Keyword(s):  
Raw Materials ◽  
Environmentally Friendly ◽  
Decomposition Process ◽  
Second Stage ◽  
Phosphorus Containing ◽  
Neutralization Process ◽  
The Absolute ◽  
Two Stages ◽  
Kinetics Of

The kinetics of the process of using phosphorus-containing mineral compounds by their decomposition, which are actual problems, has been studied. At beginning of the it have been notified that the process takes place in two stages. These stages of the process are differed from each another mainly by rate of process realization, because a rate of the first stage is much more that a rate of the second stage. This fact is a reason of the deep research of kinetic of given process. Apart from that a detailed study of these processes connect with some problems of enter prices. All these question are analizied in the work, also the information by methodical carry out of experiments. Regime parameters correlation of components, concentrations of components, a time requite for realization of process are presented. The dependence of degree by different mass correlation of components from the time realization of process are also shown. In the work the types existence of precipitate, monitite brush it are shown. On base of received date a dissolubility of the base received product are graphically presented. In the work an influence of mass correlation of CaO?P2O5 and time of process realization on precipitation is studied. It have been determined that by 650C temperature a mass correlation of the base components must be equal to one, by that a time being used on neutralization process don’t play the practical role, because its increase and decrease don’t influence practically on process indices. The results shown that by equality of components CO?P2O5=1 correlation during four hours the precipitation degree makes up to 90,66 % and during 1 hour this index is 78,2 % for duringthe remaining three during this index is increased on 12 %. By using of these received data these is a possibility determination of the optimum technological conditions for given process. it is shown that there are opportunities to achieve processivization, to increase the use of raw materials and to obtain an environmentally friendly product with the introduction of regime parameters and component ratios in the absolute state.

Quantification of analyte and interferent by multipoint analysis.

1986 ◽  
Vol 32 (9) ◽  
pp. 1648-1654 ◽  
Author(s):  
R L Czervionke ◽  
G F Johnson ◽  
N F Nuwayhid ◽  
R D Feld
Keyword(s):  
Linear Regression ◽  
Kinetic Curve ◽  
Model System ◽  
Simultaneous Equations ◽  
Multipoint Analysis ◽  
Two Stage ◽  
Second Stage ◽  
Regression Approach ◽  
Multivariable Nonlinear Regression

Abstract We have investigated the application of multipoint kinetic curve-fitting methods to the determination of an analyte in the presence of a single interferent. Our model system for the analyte-interferent was creatinine-acetoacetate as determined with the kinetic Jaffé method. We examined the utility of the following multipoint approaches: simultaneous equations, multivariable linear regression, and iterative multivariable nonlinear regression. With appropriate restrictions, all approaches could detect acetoacetate interference and quantify both creatinine and acetoacetate. A two-stage linear regression approach was both versatile and computationally simple. Interferent was detected in the first stage, and both analyte and interferent were quantified in the second stage if the interferent was assumed known and an adequate fit of the model to the data was obtained. Using the two-stage linear regression model, we obtained results for 10 ketotic patients that correlated well with results by enzymatic methods for creatinine (r = 0.976) and acetoacetate (r = 0.995); we also demonstrated that creatinine could be quantified in the presence of the antibiotic cefoxitin.

Polyethylene on Cement Spacers: An Economic Approach to an Effective Infection Eradication in a Two-Stage Knee Revision Articulating Spacers

2018 ◽  
Vol 31 (10) ◽  
pp. 986-991
Author(s):  
Junren Lu ◽  
Jing Han ◽  
Zhenjun Yao ◽  
Yi Yang ◽  
Chi Zhang
Keyword(s):  
Revision Surgery ◽  
Joint Infection ◽  
Cost Effective ◽  
Two Stage ◽  
Second Stage ◽  
Articulating Spacer ◽  
Eradication Of Infection ◽  
Total Knee ◽  
The Cost

AbstractAlthough two-stage revision surgery is generally considered as the gold standard treatment for periprosthetic joint infection (PJI) after total knee arthroplasty, the procedure is limited by the costs of commercially preformed spacers used for treatment. In this work, we aim to report a modified approach by which the cost of the spacer could be significantly reduced without compromising eradication of infection. Between 2010 and 2016, we performed a total of 11 two-stage revision arthroplasties using a surgically handmade spacer with a new polyethylene insert. Patients were aged 59 to 80 years old (mean 69.9 years), with a range of motion (ROM) between 20° and 65° on the affected knee (mean 46.4°) before the first-stage revision surgery. During the perioperative and postoperative period, functional and clinical evaluation of the patients were performed, including the determination of their articular ROM, Knee Society Knee Scores (KSKS), and Knee Society Function Scores (KSFS). All patients were followed up for an average of 2 years, ranging from 1 to 4 years. After the second-stage revision surgery, the mean ROM was increased by 46.8° (46.4°–93.2°) after the second-stage revision. KSKS and KSFS scores were recorded to increase by an average of 44.5° (range 40.4°–84.9°) and 46.9° (range 38.5°–85.4°), respectively. All 11 patients underwent a successful two-stage revision surgery, and no evidence of postsurgical infection was found during patient follow-up examination. Our results show that this personalized handmade antibiotic-loaded articulating spacer is cost-effective and efficacious.

Quantitative Determination of Plasminogen

1970 ◽  
Vol 23 (02) ◽  
pp. 191-201 ◽  
Author(s):  
H. D Bruhn ◽  
L Müller ◽  
F Duckert
Keyword(s):  
Quantitative Determination ◽  
Plasminogen Activator ◽  
Assay System ◽  
Two Stage ◽  
System Activation ◽  
Frozen Plasma

SummaryA modification of the caseinolytic assay for plasminogen is described. This assay system is characterized by the following features :1. Urokinase is used as activator achieving a complete activation of the plasminogen whereas with streptokinase caseinolytically inactive plasminogen-activator complexes are formed.2. All incubation times are reduced to the minimum which is still compatible with accuracy.3. Results are expressed in percent of a standard of ten normal plasmas.4. In this two-stage assay-system (activation of plasminogen to plasmin, digestion of casein by plasmin) both stages proceed simultaneously in the same system, thus the plasmin formed is stabilized “in statu nascendi” by the casein.5. Several conditions (stability of plasminogen in frozen plasma, use of anticoagulants, reproducibility) are defined.

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