Abstract:
A method of synthesizing a high purity product of α,α,α′,α′-tetrachloro-p-xylene is disclosed. The method includes carrying out a first stage reaction of terephthaldicarboxaldehyde with a mixture of SOCl2 and dimethylformamide (DMF) to obtain a product mixture containing α,α,α′,α′-tetrachloro-p-xylene as a major product and 4-dichloromethyl benzaldehyde as a side product; adding SOCl2 and DMF to the product mixture of the first stage reaction to undergo a second stage reaction; and to a cool water adding the resulting product mixture from the second stage reaction to obtain a solid product of α,α,α′,α′-tetrachloro-p-xylene with a purity of 90-99 mol %.
Abstract:
A method and a device for purifying 1,4-bis(bromodifluoromethyl)benzene are disclosed. In order to solve the problem of hard to purify and separate 1,4-bis(bromodifluoromethyl)benzene crude products, diphenylmethane that has a higher boiling point and does not interact with 1,4-bis(bromodifluoromethyl)benzene is mixed with the 1,4-bis(bromodifluoromethyl)benzene crude products for evaporation. Afterwards, the purity of the vaporized product is detected and only that reaching an expected purity is collected to obtain high-purity 1,4-bis(bromodifluoromethyl)benzene.
Abstract:
A data security protection method generates dynamic encryption keys and dynamic decryption keys for a host and a client during data transmission between the host and the client. The host stores a host initial key K0, and determines a host key Kn using a one-way hash function based on the host initial key K0. The client stores a client initial key K′0, and determines a client key K′n using the one-way hash function based on the client initial key K′0. Original data Rn is encrypted as encrypted data Xn using the host key Kn before being sent to the client. The client decrypts the encrypted data Xn using the client key K′n, to obtain the original data Rn.
Abstract:
A substrate with a multi-domain vertical alignment pixel structure is provided. The substrate is opposite to a counter substrate with a common electrode, and a liquid crystal layer is disposed between the substrate and the counter substrate. The substrate includes a scan line and a data line, an active device, first and second patterned pixel electrodes and a voltage drop layer. Wherein, the first patterned pixel electrode provides a first electrical field to the liquid crystal layer, and the second patterned pixel electrode provides a second electrical field to the liquid crystal layer. The voltage drop layer makes the first electrical field smaller than the second electrical field.
Abstract:
The present invention provides a lamp device. The lamp device of the present invention comprises a lamp holder, a frame on the lamp holder, and a lamp tube having a height. At least one third of the height of the lamp tube is contacted with the frame to improve mechanical strength of the lamp tube.
Abstract:
A method for producing 1,4-bis(difluoromethyl)tetrafluorobenzene is disclosed, which has the following steps: (a) mixing 1,4-bis(dichloromethyl)tetrafluorobenzene, a catalyst, an aprotic polar solvent, and an alkali metal fluoride to form a reaction mixture; (b) heating the reaction mixture; and (c) purifying the resultant to obtain 1,4-bis(difluoromethyl)tetrafluorobenzene.
Abstract:
A method and a device for purifying 1,4-bis(bromodifluoromethyl)benzene are disclosed. In order to solve the problem of hard to purify and separate 1,4-bis(bromodifluoromethyl)benzene crude products, diphenylmethane that has a higher boiling point and does not interact with 1,4-bis(bromodifluoromethyl)benzene is mixed with the 1,4-bis(bromodifluoromethyl)benzene crude products for evaporation. Afterwards, the purity of the vaporized product is detected and only that reaching an expected purity is collected to obtain high-purity 1,4-bis(bromodifluoromethyl)benzene.
Abstract:
A barrier rib structure of plasma display panel is disclosed. The barrier rib structure includes a plurality of vertical barrier ribs arranged in parallel, a plurality of first horizontal barrier ribs connected to one side of the vertical barrier ribs, and a plurality of second horizontal barrier ribs connected to the other side of the vertical barrier ribs, in which the first horizontal barrier ribs are disposed alternately with corresponding second horizontal barrier ribs for forming a plurality of double blockade structures. Additionally, a gas passage and a plurality of electrical discharge spaces are formed between the double blockade structures.
Abstract:
A method for transferring TCPX (α, α, α′, α′-tetrachloro-p-xylene) into TFPX (α, α, α′, α′-tetrafluoro-p-xylene) is disclosed, which comprises the following steps: (a) providing a first reactant comprising TFPX; (b) mixing the first reactant with alkali metal fluorides, TCPX and phase transfer catalyst(s) to form a mixture, wherein the alkali metal fluorides is KF, CsF, NaF, LiF or the combination thereof, the phase transfer catalyst(s) is quaternary ammonium salt, quaternary phosphonium salt or the combination thereof; and (c) heating the mixture.
Abstract:
An apparatus for driving an interlaced plasma display panel (PDP), including a delay device, an image upper and lower edge detection device, an image border processing device, an image processing and analog control loop. The delay device receives an image signal, delays the image signal for two fields and outputs the delayed image signal. The image upper and lower edge detection device receives and analyzes the image signal, outputs the image upper and lower edge positions, saves and provides the odd field upper and lower edge data of the image signal. The image border processing device outputs the image signal after border processing according to the delayed image signal, the image upper and lower edge positions, the odd field upper and lower data. The image processing and analog control loop outputs a driving signal according to the image signal after border processing and the image upper and lower edge positions.