BA threads

Since 1965, British industry has been urged to adopt the ISO (International Organization for Standardization) metric thread as a first-choice thread system, with the ISO inch (unified) thread as the second choice. The British Standard Whitworth (BSW), British Standard Fine (BSF), and British Association (BA) threads would then become obsolete. The British Standard Pipe (BSP) thread is to be retained. The changeover has been extremely slow in taking place, and all these threads are available and still in use. 

In equations 7.27 and 7.28 m(BA), m(cot), m(crbl), and m(wr) are the masses of benzoic acid sample, cotton thread fuse, platinum crucible, and platinum fuse wire initially placed inside the bomb, respectively n(02) is the amount of substance of oxygen inside the bomb n(C02) is the amount of substance of carbon dioxide formed in the reaction Am(H20) is the difference between the mass of water initially present inside the calorimeter proper and that of the standard initial calorimetric system and cy (BA), cy(Pt),cy (cot), Cy(02), and Cy(C02)are the heat capacities at constant volume of benzoic acid, platinum, cotton, oxygen, and carbon dioxide, respectively. The terms e (H20) and f(sin) represent the effective heat capacities of the two-phase systems present inside the bomb in the initial state (liquid water+water vapor) and in the final state (final bomb solution + water vapor), respectively. In the case of the combustion of compounds containing the elements C, H, O, and N, at 298.15 K, these terms are given by [44]... 

Metrohm and BAS have also introduced improved DME models capable of operating in the SMDE mode. The Metrohm electrode (Fig. 14.6b) has a needle valve and small-bore capillary. Much of it is pneumatically controlled. The BAS version (Fig. 14.6c) is called the controlled growth mercury electrode (CGME). It is based on the work of Kowalski, Osteryoung, and coworkers [30]. Its features include a low-resistance electrical contact to the mercury thread in the capillary via a stainless steel tube and a fast response valve. The fast valve has allowed unique experiments to be performed where precise control of mercury drop growth during the experiment is desirable [31-33]. The BAS (Fig. 14.7), EG G Princeton Applied Research (Fig. 14.8), and Metrohm (Fig. 14.9) electrodes offer this easy and reproducible drop renewal in fully equipped cell stands. 

Figure 14.10 Mercury thread electrode design and electrochemical cell arrangement (BAS).

The large fraction of threading dislocations with ba can be understood by analyzing the misfit dislocations at the interface between the buffer layer and the ZnO film. Figure 4(a) displays a zone-axis high-resolution TEM (HRTEM) image of the interface of the sample depicted in Fig.3. The 1-100 Fourier-filtered image Fig.3(b) shows that the misfit dislocations... 

Threads in this range have extremely fine pitches and are used for applications less than inch diameter in preference to BSW or BSE They are designated by a number, e.g. 4 BA (Appendix 4). 

Appendix 4 basic form for British Association threads (BA), Fig. A4... 

Fig. 1. Infection and early development of root nodules. (A) Infection thread (IT) and curled root hair (CRH) 48 hr after inoculation. (B) Nodule meristem differentiation in root cortical parenchyma prior to infection thread proliferation. Arrowhead points to mitotic figure (M). (C) Bacterial (Ba) release from infection thread into host cell cytoplasm. Bacteria are surrounded by a polysaccharide matrix (P) within the infection thread and immediately upon release. (D) After release from the infection thread bacteria (Ba) are enclosed within the peribacteroid membrane (PBM) and the polysaccharide matrix (P) formerly surrounding the bacteria is degraded. Bars indicate approximate sizes. 

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