Posts by date :

Slag and Cement

Posted by Juan on June 20, 2014 with Comments Closedas

Typically, individual surface finely slag is 2500 – 3500 cm / city Fine ground slag, added to the cement, significantly affect the structure formation of cement stone. Microsilica is a waste product of silicon alloys of ferrosilicon, crystalline silicon, etc. In the process of melting the charge and recovery of quartz at temperatures above 1800oS gaseous silicon is formed, which when cooled and exposed to air oxidizes to SiO2 and condenses in the form of ultrafine particles of silica. SiO2 content in the silica fume is 85-98%. From other active mineral additives microsilica has a very small size particles (0.1-0.5 microns) and high specific surface (18-25 m / g). Located in the concrete in the pores of cement, microsilica improves the density and thus strength, impermeability and durability of concrete.

To seal the concrete require fewer mineral supplements (mixture porosity 'cement – aggregate' is relatively small) than when diluted in a wide range of cement, so the usual flow of microsilica in concrete is 5-15% of weight of cement, which is lower than other mineral supplements. In addition, in this case the interaction in concrete, Ca (OH) 2 and SiO2 is relatively limited, and it persists for a long time needed to per boards reinforcement alkaline corrosion. In the dry form because of the dispersion of ultra-high bulk density silica fume is only 0.15-0.2 t / m , making it difficult to transport. In the production of concrete is usually used pre- granular or briquetted microsilica, which greatly facilitates its transport and use. Organo-mineral supplements are combining into a single system of organic and mineral components having a specific modifying effect. Studies have shown that fine mineral supplements improve the efficiency of the plasticizers and, conversely, the latter contribute to positive action E mineral fillers on the structure of the concrete mix and concrete. NIIZhB suggested that organo-mineral complex modifier of the structure and properties of concrete MB-01 polyfunctional including superplasticizer C-3 (6-12% of weight) and microsilica and represents a powdered product bulk density of 750-800 kg / m with grain size up to 100 microns.

As a regulator of hardening (PT), injected into it organophosphorus complex. In applying this additive increases the keeping consistency of concrete mix, it is possible to obtain concrete with a strength above 100 MPa, low permeability and high durability. On the same principle established organo-mineral MB-C modifier. It includes a superplasticizer C-3, microsilica and fly ash-ash, in which 30-50% of silica fume replaced with a more affordable ash, ash, without noticeable loss performance additives. In general, organo-mineral Supplements are available in powder-shaped form, which facilitates their introduction into the concrete mix during its preparation. When designing the application in concrete additives necessary to carry out technical and economic calculations for predict the expected effect. It should be borne in mind that the use of additives in concrete technology, requires additional costs for a warehouse addition, highways, site preparation additives to additional congestion on the concrete mixing shops and factories. Some additives are relatively expensive and more scarce. It is therefore necessary to use additives in the first place where they use gives the greatest technical and economic effect. C the current situation and outlook for the Russian market additives for concrete, cement, CAS can be found in the records of the Academy of IKAR industrial markets "The market for supplements concrete, cement and dry mortar in Russia. "

Press Ctrl

Posted by Juan on June 17, 2014 with Comments Closedas

Each inode is identified by an integer, unique within the system files and directories contained a list of pairs consisting of a number of inode and name identification that allows access to that file, every file has one inode, but may have more than one name in different or even in the same directory to facilitate location. “In our case, our file inode is 512 495, this is the ID of our file on the system. When you delete a file with the rm command, what we do is delete the reference to the inode in question, for a time that inode will continue to exist in our system but we can not see and it appears that the deleted file has disappeared from our system. If any program is accessing the file that we deleted, are lucky. The program in question will have a reference to the inode of the deleted file and provided they do not close this program we can retrieve the contents of this file.

(A practical case that many of us ever happened to the log file to delete any system service (apache, postgresql, mysql. etc) while the service is working) Here is a full session since we delete a file until you recover: We open our file example with less (for example) less fichero_pruebas.txt THIS IS A TEST FILE TEXT fichero_pruebas.txt (END) Press Ctrl + z to suspend the less program without stopping it (the program remain open, accessing our database, but suspended) less fichero_pruebas.txt 1 + Stopped less fichero_pruebas.txt We found that our file is intact: ls-li fichero_pruebas.txt 512 495-rw-r – r – 1 root root 39 02/04/2008 22:28 fichero_pruebas.txt We erase … 😉 accidentally rm test.txt ficheros_de We found that not exist in our directory ls ls-li fichero_pruebas.txt: fichero_pruebas.txt: No such file or directory As discussed above, if we have a program accessing the file we’re lucky. Use lsof to see if any program is accessing the file that we deleted: lsof grep user fichero_pruebas.txt less 4r REG 28 410 3.1 39 512 495 / home / user / fichero_pruebas.txt (deleted) should not be a surprise that our less this program accessing our file deletion. The columns we are interested in this line are the first (PID of the program accessing the file, 28 410), and the fourth, the ‘file descriptor’ (4r) with reference to our file inode (512 495). With this information we go to the virtual filesystem / proc information on our linux system.

ls-l / proc/28410/fd/4 lr-x —— 1 user user 64 02/04/2008 22:38 / proc/28410/fd/4 – / home / user / fichero_pruebas.txt ( deleted) As expected, a reference to the deleted file. All you have to do now is copy the data to which / proc/28410/fd/4 this reference. For this we can easily use cp cp / proc/28410/fd/4 fichero_pruebas.txt.restaurado Now no matter what our program has finished running less because our already deleted file recovered. cat fichero_pruebas.txt.restaurado THIS IS A TEST FILE TEXT This article must have a little luck to keep our database, but in future articles we will see other techniques to use when luck is not on our side. That’s it for today, enjoy it.

Pablo Freire

Posted by Juan on June 16, 2014 with Comments Closedas

Moreover, I recognize the imperious necessity of if reviewing the concepts that if have on the Mathematics, that is so important in the life of the man. As well as of the methods and techniques used in its education. Regarding this if it places Pablo Freire (1998, P. 26-29): I do not fear to say that reality in education inexists where a learning does not result where the apprentice if did not become capable to recriar or to remake the taught one. … in the conditions of true learnings the educandos ones go if transforming into real citizens of construction and of the reconstruction of knowing taught …. It is thus perceived, that it is part of the teaching task not only to teach contents, but also to teach to think certain.

The biggest importance of this study is the contribution that will give for all the professionals in general, that they work in the education of the Mathematics, therefore promotes a study dialtico enters the main points of the theories partner-interacionistas correlated to the educational ideas on the paper of the school and the importance of the use of the technology in classroom offering to them chances to reflect on its paper as mediator in the process of teach-learning in this area, inside of ours world contemporary. 2 METHODOLOGY The methodology of used research was of qualitative matrix, translating and expressing the direction of the phenomena found throughout the work. This type of research has inductive approach and one descriptive character of the studied given phenomena and/or where it has an interactive and direct contact of the researcher with the study object. As procedure of collection of data a bibliographical research was carried through sidewalk in books, magazines and too much publications of studious pedagogos and that if had dedicated the research educational and had launched important theories on the Mathematical Education.

Managing Barcode

Posted by Juan on June 15, 2014 with Comments Closedas ,

It's important to remember for yourself what the product code (part number, a unique identifier) and a barcode – a completely different concept, and, in general, no relation to each other have not. Understanding this difference is easy to explain why one item (item) can have several different bar codes – any additional information that […]