摘要:
A sampler for taking a defined amount of sample of a fluid medium from a sample-taking site, with a tubular line, which can be brought into contact with the fluid medium at the sample-taking site, for conducting the fluid medium into at least one sample storing receptacle, with a pump. The pump moves the medium via the tubular line into the sample storing receptacle. A sequence control activates the pump, such that it dispenses the defined amount of sample into the sample storing receptacle. The pump is a rotary piston pump.
摘要:
The invention is directed to an illumination device for microscopes which is provided with a halogen lamp with a reflector and a filament extending in direction of the optical axis and a scatter disk and which enables a homogeneous illumination of the visual field without additional optical components.
摘要:
Processes for the separation of a potassium salt of a perfluoroalkanoic acid having at least 1 and at most 12 carbon atoms per molecule or a mixture of potassium salts of a homologous mixture of the said perfluoroalkanoic acids from an aqueous solution that also contains a substantial proportion of one or more watersoluble salts of inorganic acids which process comprises extracting at room temperature the said aqueous solution with an organic solvent which is at least partially miscible with water and in which potassium salts of the said perfluoroalkanoic acids are soluble, the said organic solvent being selected from the group consisting of alkanols having at least 3 and at most 5 carbon atoms per molecule, ketones having at least 3 and at most 7 carbon atoms per molecule, N,N-dimethylformamide and dimethyl sulfoxide, and subsequently recovering the potassium salt of the perfluoroalkanoic acid or mixture of potassium salts of the homologous mixture of perfluoroalkanoic acids.
摘要:
A condenser arrangement for brightfield illumination and/or darkfield illumination for optical microscopes comprises in a housing basic optics having at least one lens, at least one front optics which can be inserted into the illumination beam path in front of the basic optics, and means for inserting the front optics into the illumination beam path of the microscope. A first swiveling arm and a second swiveling arm are swivelably arranged at the housing of the condenser. The first swiveling arm carries first front optics with a high aperture for brightfield illumination and the second swiveling arm carries second front optics for darkfield illumination. The two swiveling arms are arranged at a defined distance from the shared basic optics of the condenser in direction of the optical axis of the illumination beam path. An aperture iris diaphragm is provided on the object side in front of the basic optics and is opened when the cardioid optics are inserted. Further, a darkfield slide with an annular mirror element is provided on the object side at the housing. Operator's controls serve to swivel the two swiveling arms for moving the darkfield slide and for adjusting the aperture iris diaphragm.
摘要:
An optical arrangement with telecentric beam region for imaging objects, preferably a microscope, comprises in a main beam path at least one infinity-imaging objective and at least one eyepiece with an eyepiece intermediate image plane and a tube lens of suitable focal length which is arranged between the latter at a fixed distance from the objective. At least one optical element in the form of a beam splitter module or beam splitters for laterally splitting off at least a first partial beam path is provided in the space between the objective and the tube lens in which the telecentric beam path is located. A tube lens is located at a suitable distance from the objective in each of these first partial beam paths. At least a second partial beam path is branched off from at least one of these first partial beam paths and a tube lens is located at a suitable distance from the objective in each of these second partial beam paths. The tube lenses arranged in the individual partial beam paths have the same focal length or different focal lengths.
摘要:
The invention is directed to a method of differential interference contrast in which the object is illuminated by natural light and the light coming from the object is first polarized after passing through the objective. The observation is carried out with a shearing interferometer which is known per se.
摘要:
In a microscope such as for the examination of specimens in specimen vessels, a device for changing objectives is provided. The microscope includes at least a first objective. The device comprises an arrangement for providing an operating control so that the at least first objective can be raised and lowered vertically and is displaceable horizontally vertical to an optical axis of the microscope.
摘要:
Straight chain perfluoroolefins compounds of medium length with terminal or double bonds and a minor proportion of trifluoromethyl side chains or mixtures of such perfluoroolefins with perfluoro paraffins of equal chain length and corresponding structure, the perfluoroolefins being present in the mixture in an amount of 40 to 70%. The compounds are valuable as highly reactive intermediate products in the production of surface active agents. The compounds are made by subjecting a highly fluorinated organic compound to degradation by means of a high energy radiation of a density of 0.3 to 3.0 W/cm.sup.2 effected in a radiation chamber which has been subjected to a preceding rinsing with an inert gas or with a monomeric highly fluorinated organic compound.
摘要翻译:具有中等长度的具有末端或双键的直链全氟烯烃化合物和少量比例的三氟甲基侧链或这种全氟烯烃的混合物与具有相等链长和相应结构的全氟链烷烃的混合物中,全氟烯烃以40至70的量存在于混合物中 %。 这些化合物在表面活性剂生产中作为高反应性中间产物是有价值的。 化合物是通过使高度氟化的有机化合物通过在用惰性气体进行先前漂洗的辐射室中进行的,在0.3至3.0W / cm 2的密度的高能量辐射下进行降解而制成的, 单体高氟化有机化合物。
摘要:
A prism changing device for a microscope for carrying out interference contrast examinations has a carrier for attaching the prism changing device to the microscope and a holder with at least two receptacles for prisms which is held at the carrier so as to be movable relative to it between at least two work positions in which one of the receptacles is arranged in the beam path of the microscope when the prism changing device is attached to the microscope. At least one of the receptacles is displaceable and rotatable relative to the holder in a plane transverse to the beam path of the microscope.
摘要:
A semiconductor laser diode, and a method for producing the semiconductor laser diode, includes a waveguide being terminated by a back facet and a front facet and a front facet coating and a back facet coating having a reflectivity providing for controlled decoupling of light at the front facet from the standing lightwave in the waveguide. The front facet coating includes a stack of layers providing for a phase shift of the standing lightwave within the waveguide such that the intensity of the lightwave at the front facet, where the light is decoupled from the standing lightwave, has a relative minimum.