摘要:
A power supply apparatus, in which the three phases of an alternating-current main are connected each through rectifier elements connected in antiparallel to the primary winding of a three-phase transformer. The secondary windings of this transformer are connected through rectifiers to a load device, such as an electron beam gun or other such device which produces short-circuits while in operation. Measuring sensors are provided on the primary AC side which, in the presence of an excess current on the primary AC side, block controlled rectifier elements. The blocking takes place very rapidly because GTO thyristors are used as rectifier elements. The decay of the magnetic energy in the transformer is achieved by the fact that the primary side of this transformer is connected in delta.
摘要:
A static casting method for a hollow cast product using a mold with bottom comprising a top lid, a core and an outer mold section, the core being attached to the top lid and disposed inside the outer mold section. The outer mold section includes a lateral mold section and a lower mold section. The lateral mold section is formed at its inner peripheral wall portion with a composite cooling section by stacking chiller blocks and interposing therebetween refractory sands and at its outer wall portion with refractory sands. Cooling pipes include first and second pipes. A first pipe extends longitudinally through the refractory sands at the outer wall portion and a second pipe extends longitudinally through the inner wall portion in contact with at least a part of each of the chiller blocks, the first and second pipes being connected at their lower portions through the bend portion. The chiller blocks are cooled by water flowing in the second pipes. The entire casting cavity is first filled with molten metal. Then cooling water is passed through the cooling pipes until solidification of the metal is complete. Thereafter the supply of water is stopped and water remaining in the pipes is discharged.
摘要:
A process for the preparation of neopentylamine which is virtually free from amines with a higher degree of alkylation which comprises contacting neopentanol with ammonia at a temperature of 200.degree. to 300.degree. C. in the presence of a hydrogenation catalyst. The process can be carried out under increased pressure and in the presence of catalytic amounts of hydrogen.
摘要:
A process for the preparation of a 2-hydroxycarbazole of the formula ##STR1## wherein R.sup.1 represents hydrogen, halogen or an optionally substituted alkyl, aryl or alkoxy radicalWhich comprises contacting a diphenylamine of the formula ##STR2## wherein R.sup.1 has the above-described meaning andR.sup.2 represents halogenWith a base at an elevated temperature in water and/or an organic solvent or diluent.
摘要:
Pure thyrocalcitonin (.alpha. and .beta.) and process for its manufacture from thyroid gland tissue by extraction with a solvent system containing water and a lower alkanol at a pH of about 1-6.
摘要:
The invention concerns a converter arrangement for electrode melting furnaces, particularly for electric slag remelting of metals. A current regulator in the form of a PI controller is associated with the converter arrangement. The former is influenced by an actual current value, a reference current value, and additionally, by a control quantity. The control quantity replaces the current regulation of the regulator by a voltage control in dependence on periodic or aperiodic conditions which may be due to operational causes or to trouble and interfere with the melting process in the furnace. More particularly, for the duration of such conditions, the control quantity causes the output voltage of the regulator, which voltage acts on the control unit feeding the converter, to be limited upward to an adjustable value.
摘要:
Novel lines of Brassica juncea yield an edible oil that has properties similar to canola oil. More specifically, the oil has an oleic acid content of at least 55% by weight, a linoleic acid content of less than 25% by weight, a linolenic acid content of less than 14% by weight, a erucic acid content of less than 1% by weight, a palmitic acid content of less than 6% by weight, a stearic acid content of less than 2.5% by weight, and a total saturated acid content of less than 7.1% by weight. The novel lines of B. juncea plant have a lineage that includes both lines J90-3450 and J90-4316, these being known lines of B. juncea, and may be formed by conventional cross fertilization or other means. The novel lines can be grown in harsher environments than conventional canola species and are high-yielding and disease-resistant.
摘要翻译:新鲜的芥菜系产生具有类似于油菜油的性质的食用油。 更具体地说,油的油酸含量为至少55重量%,亚油酸含量小于25重量%,亚麻酸含量小于14重量%,芥酸含量小于1 重量%,棕榈酸含量小于6重量%,硬脂酸含量小于2.5重量%,总饱和酸含量小于7.1重量%。 B. juncea植物的新品系具有包括J90-3450和J90-4316两种品系的品系,这些品系是B. juncea的已知品系,并且可以通过常规交叉施肥或其他方式形成。 这些新品系可以在比传统油菜种类更苛刻的环境中生长,并且具有高产量和抗病性。
摘要:
An energy-absorbing device, particularly for rolling stock to provide protection therefor when potentially damaging impact occurs, includes first and second tubular elements which are fitted into one another and which are of unlike material.
摘要:
The invention concerns a measurement sensor for the detection of temperatures in metal or alloy melts. This measurement sensor consists of a thermocouple (41) surrounded by a ceramic capillary (24) which is closed at its end by means of an adhesive (45) or the like. This measurement sensor is directly, i.e. without further sheathing, introduced into the melt (FIG. 3a).
摘要:
In automatic melting crucible tipping it is important that, starting from a certain angular position, the melting crucible (1) is tipped according to a predetermined model until emptying is complete. This model can be obtained, for example, by the so-called teach-in process and can be stored in an analog or digital memory (89). In order to prevent abrupt movement of the crucible (1) when the molten material touches the pouring lip (3) of the crucible (1) when the pour-lip angle has been reached, according to the invention a correction arrangement (108, 109, 37) is provided which enables the tipping process to proceed continuously and without abrupt movements even in the case of different pour-lip angles.