97 research outputs found
Recommended from our members
United States Bureau of Mines Bulletin 382
From Schedules, Approvals, and Approval Plates: " This schedule has been revised from time to time to conform with information gained from testing a large variety of equipment and to bring the requirements in line with new developments in the art. As the approval plate on a machine evidences compliance with the safety requirements established by the Bureau the user, in fairness to the Bureau and the manufacturer, should not operate such a machine if it has been changed from the design approved without authority or if it has become unsafe through neglect or accident. The machine should be in proper condition, or the approval plate should be removed and destroyed.
Recommended from our members
United States Bureau of Mines Bulletin 543
From Introduction: "The present publication includes an appendix listening seven satisfactory fuels available for use in permissible flame safety lamps and shows where the fuels are available. This publication also includes an appendix listening manufactures of flame-resistant trailing cables, with the corresponding symbol that must be used by these manufactures in marketing trailing cables that have passed the test for flame resistance contained in Schedule 2E.
Preliminary investigations of storage battery locomotives : specifications laboratory tests permissible schedule /
"Publications on investigations of electrical equipment": p. 34-35.Running title: Storage-battery locomotives.First edition, October, 1920. cf. verso of t.-p.At head of title: Department of the interior. John Barton Payne, secretary. Bureau of mines. Frederick G. Cottrell, director.Includes Bibliographic references. Bibliography: p.Mode of access: Internet
Recommended from our members
United States Bureau of Mines Bulletin 313
From Introduction: "The purpose of this paper is therefore to give essential data in regard to the construction of approved storage-battery locomotives and power trucks.
Recommended from our members
United States Bureau of Mines Bulletin 343
From Description of Permissible Loaders and Conveyors: "The following descriptions of permissible loading machines and conveyors now included in the bureau's list of approved equipment are given to indicate to mine operators not only the types available but also show to some extent the special features employed in designing machines that minimize the hazard of gas and dust ignitions. Furthermore, the authors hope that the descriptions will have some value to manufactures who may contemplate entering this field of special design.
Response of fibroblast activity and polyelectrolyte multilayer films coating titanium
International audienceOBJECTIVES:The study of surface properties is a recent and crucial issue in the biomaterial fields applied to Odontology. The reference biomaterial in dental implantology is titanium. The principal objective is a perfect bio-integration in the oral ecosystem, both in terms of mucosal and bone tissues. The aim of this work was to optimize the tissue-titanium interface by applying polyelectrolyte multilayer films on the surface of titanium.METHODS:The experimental study was undertaken on pure titanium samples. Two types of film ending with polycations or polyanions were selected. Both film types were built with a first poly(ethyleneimine) (PEI) base layer and composed either of poly(styrene sulfonate) (PSS) and poly(allylamine hydrochloride) (PAH) or of hyaluronic acid (HA) and poly(l-lysine) (PLL) layers. Final architectures were as follows: PEI-(PSS/PAH)(10), or PEI-(PSS/PAH)(10)-PSS, or chemically cross-linked PEI-(HA/PLL)(10) or PEI-(HA/PLL)(10)-HA. An analysis of the physicochemical characteristics of the surfaces was carried out by tensiometry measurements (dynamic contact angle, wettability, contact angle hysteresis) and atomic force microscopy. A biological study with human fibroblasts was followed over a 7-day culture period at days 0, 2, 4 and 7 to observe the cellular response in terms of morphology (scanning electron microscopy) and viability (Mosmann's test).RESULTS:The results showed that polyelectrolyte multilayer films could be successfully deposited onto titanium as previously described for glass or composite. Fibroblast adhesion and proliferation was strongly dependent on film type. SEM observations of cells on the different films agreed with the viability cell test. Furthermore, films containing PSS/PAH generated a better cellular response than films containing cross-linked HA/PLL.CONCLUSION:PSS/PAH polyelectrolyte films coating titanium could represent a new approach for oral bio-integration with great potential for clinical application in the fields of dental implantology. More particularly, the specific biofunctionalization of PSS/PAH films coating titanium could be envisioned by introducing layers of molecules that encourage the bio-integration process between the films
Recommended from our members
United States Bureau of Mines Bulletin 541
From Scope of Paper: "This paper mainly consist of a discussion of design features of explosion-proof units that have been employed in the construction of permissible machines.
- …