85results about How to "Big price advantage" patented technology

The invention belongs to the technical field of vibration test, in particular to a thin-walled structure part vibration test device and a method based on a piezoelectric ceramic vibration exciter. The device comprises a signal generator, a piezoelectric ceramic drive power supply, a piezoelectric ceramic vibration exciter, a feedback attenuator, a laser vibration meter, a data acquisition analyzer and an upper computer. The method comprises the steps of performing modality test on a thin-walled structure part, determining a linear relationship between excitation voltage and critical excitation frequency of the signal generator and calibrating an excitation force of the piezoelectric ceramic vibration exciter based on a cantilever theory. According to the device and the method, an excitation signal can be effectively acquired; the magnitude of the excitation force when the piezoelectric ceramic vibration exciter excites the structure part is defined; the stable designated excitation force and the linear excitation signal of the excitation frequency can be generated; influencing factors of non-linear piezoelectric ceramic excitation are effectively eliminated; the piezoelectric ceramic vibration exciter is adopted to realize high-frequency vibration excitation; additional mass is low; and the device is convenient to use.

The invention relates to a step-down constant current LED drive circuit for automobile lighting. The circuit comprises an isolating circuit module (1), wherein the input end of the isolating circuit module (1) is electrically connected with a power supply (8), and the output end of the isolating circuit module (1) is electrically connected with an MOS transistor drive circuit module (2) and a converting circuit module (3); a Vin terminal of a PWM control chip (6) is electrically connected with the power supply (8), and a Vout terminal of the PWM control chip (6) is electrically connected with the MOS transistor drive circuit module (2) and the converting circuit module (3); the output end of the converting circuit module (3) is connected with an LED lamp set (9); one end of a feedback circuit module (5) is connected with the output of the converting circuit module (3) and the LED lamp set (9), and the other end of the feedback circuit module (5) is connected with an FB terminal of the PWM control chip; and a protection circuit module (4) is arranged between an earth terminal of the LED lamp set (9) and an SCP terminal of the PWM control chip. The drive circuit of the invention not only make the LED emit light constantly, but also has a short-circuit protection function, high rate of qualified products and low cost.

The invention relates to a method for preparing aqueous polyurethane. It comprises following steps: employing polyisocyanates bridging agent, proceeding copolymerization with excess aqueous polyether, liquid ploydimethyl oxosilane ternary block and getting ployoxosilane-polyether polymer, introducing polyurethane and organic silicon when generating carbamate with carbamate to main chain, adding chain propagation agent for chain propagation reaction and getting preploymer containing hydrophilic group; adding mixture of polyhydroxy compound and dissolvent into reaction system for second chain propagation reaction; neutralizing by adding neutralization agent, adding water for emulsification, adding polyamine for chain propagation; distilling to remove dissolvent after reaction and getting aqueous polyurethane modified with aqueous polyurethane-polyether polymer. The product possesses characteristics of polyurethane and polysiloxane, the storage stability, mechanics property and comprehensive performance is increased and it mainly is used as pigmentum and aqueous industrial coating material.

The invention discloses a bergmeal-based lithium sulphur battery cathode material as well as preparation and application methods thereof. The cathode material uses bergmeal as the skeleton, and elemental sulfur is injected into the bergmeal, so as to obtain sulfur-bearing composite material, and then the sulfur-bearing composite material is coated with a conductive material. By adopting the bergmeal, the dissolution of polysulfide can be reduced and the volume expansion of sulphur during charge-discharge process is restrained, and the cycling performance of lithium sulphur batteries is improved. Conductive material is used for coating, so that the electrical conductivity of material is improved and the capacity of the lithium sulphur batteries is increased. The lithium sulphur battery cathode material is simple in preparation technology, and the bergmeal belongs to natural environmentally-friendly material, and is low in cost and benificla to the industrialization of the lithium sulphur batteries. Meanwhile, the introduction of the bergmeal also promotes the industrial transformation and upgrading of the nonmetallic minerals.

Aiming at the problems in the prior art that the silica aerogel is high in price and the heat conductivity coefficient of an ordinary thermal insulation material is large, the invention particularly relates to a carbon aerogel thermal insulation material and a preparation method thereof. The carbon aerogel thermal insulation material consists of the following components in parts by weight: 100 parts of a man-made inorganic fiber, 0-200 parts of a carbon material, 0.5-2.0 parts of a dispersing agent and 0.5-2.0 parts of an adhering agent. The carbon aerogel thermal insulation material provided by the invention can be a powder material, a slurry material, a felt material or a plate material in state. The carbon aerogel thermal insulation material has the advantages of small heat conductivity coefficient and moderate price, is easy to construct and popularize, and can be widely applied to insulation of buildings, industrial equipment and pipelines; and the preparation method is low in cost and simple and easy to operate.

The invention relates to PVC heat stabilizer, in particular to heat stabilizer applied to decoration of PVC materials, a preparation method and application thereof. The barium-zinc liquid stabilizer is prepared from the following components in percentage by weight:, 20.0 to 35.0 percent of sodium iso-octoate, 10.0 to 15.5 percent of oleic acid, 8.5 to 12.8 percent of barium monohydrate, 1.0 to 5.0 percent of zinc oxide, 5.0 to 10.5 percent of diethylene glycolmonobutylether, 1.0 to 3.0 percent of antioxidant 1010, 1.0 to 4.5 percent of bisphenol A, 1.0 to 3.0 percent of beta-diketone, 5.0 to 10.5 percent of anti-separation agent, and 20.0 to 35.0 percent of DOP, wherein the total amount of components is 100 percent. The invention solves the problem that products have foreign smell based on raw materials, simplifies the production process by a one-step synthesis method, has more convenient operation, and has the effects that: firstly, the stabilizer saves energy consumption and reducing pollution; secondly, the stabilizer has high value advantage compared with international products with the same function and has better competitive force; and thirdly, the stabilizer belongs to green and environment-friendly product, and has strong vitality.

The invention relates to concentrated nutrient solution, nutrient broth and production methods thereof. The concentrated nutrient solution consists of the following raw materials in parts by weight: 26.5-30.5 parts of sea cucumber intestines, 69.5-73.5 parts of pure water, 0.05-0.1 part of protamex and 0.05-0.1 part of flavorzyme; the nutrient broth comprising the concentrated nutrient solution as a main raw material comprises the following raw materials in parts by weight: 99 parts of concentrated nutrient solution, 0.5 part of common salt, 0.25 part of hydrolyzed vegetable protein, 0.15 part of yeast extract and 0.1 part of monosodium glutamate; after scientific extraction, a sea cucumber mucopolysaccharide and sea cucumber saponin concentrated nutrient solution product of high added value is obtained, so that the utilization rate and the added value of the sea cucumber intestines are improved, and resource waste is avoided; and health-care products such as oral liquid, capsules and the like can be continuously developed by utilizing the product provided by the invention as a main raw material, particularly large price advantages can be achieved in comparison with the sea cucumber mucopolysaccharide and sea cucumber saponin product extracted by taking the sea cucumber as the main raw material, and the production cost is reduced.

The invention provides application of a Ni-based catalyst in an anode of a direct borohydride fuel cell. Active components of the catalyst consist of Ni and one or more metal elements in I B and VIIIB groups; the atomic ratio of the Ni to other metal active components in the catalyst is 99:1-8:1; and the active components in the catalyst account for 5 to 80 percent and the balance is a C carrier.A small amount of one or more metal elements in the I B and VIII B groups are added into the Ni-based catalyst to obviously improve the stability and activity of the catalyst; and when the catalyst is used as a catalyst for the anode of the direct borohydride fuel cell, the direct borohydride fuel cell shows excellent performance.

The invention provides an internal pressure type swimming pond adopting an assembled structure and a multifunctional swimming pond tent. The swimming pond wall of the swimming pond comprises a swimming pond wall frame body, a pond wall inner wall plate connected to the inner side of the swimming pond wall frame body and a pond wall outer decorating plate connected to the outer side of the swimming pond wall frame body, wherein the swimming pond wall frame body comprises supports arranged at intervals and connecting pipes connected among the supports; the connecting pipes comprise a row of inner connecting pipes and a row of outer connecting pipes; the inner connecting pipes are arranged on the inner sides of the supports from the top down; the outer connecting pipes are arranged on the outer sides of the supports from the top down; the side surface on the side, adjacent to the swimming pond wall frame body, of the pond wall inner wall plate leans against the inner connecting pipes; the side surface on the side, adjacent to the swimming pond wall frame body, of the pond wall outer decorating plate leans against the outer connecting pipes; the pond wall inner wall plate and the pond wall outer decorating plate are connected with the supports through upper pressure plates. According to the swimming pond, the pond wall outer decorating plate can be hung while no steel-structure sway brace is arranged, so that the swimming pond has rich and colorful appearance styles, is very beautiful and is especially appropriate in a square shape.

The invention belongs to the field of an inorganic functional material, and discloses a magnesium dioxide / carbon black composite material and preparation method and application thereof. The magnesiumdioxide / carbon black composite material is prepared by taking carbon black as a raw material, adding the carbon black into deionized water to prepare a carbon black solution, adding the carbon black solution into a permanganate solution to obtain a mixture, heating the mixture in water bath, performing ultrasound and performing filtering, washing and drying. The preparation method is simple in process and available in raw material, and industrial production is easy to implement. The composite material has good oxidization-reduction activity and stability under an alkali condition, is simple tooperate and easy to control, amplify and synthesize, is simple in equipment, short in consumed time and is environmental-friendly; and the composite material can be applied to a zinc-air battery andhas performance equivalent to that of a Pt / C catalyst in the zinc-air battery.

A graphic instrument for measuring the admittance circle of a piezoelectric ceramic transducer in order to indicate its application is composed of the hardware consisting of signal generator, operating and acquisition circuit and data communication unit, and the PC software consisting of data communication, user interface and data processing.

The invention discloses an evening primrose oil processing method which is characterized by comprising the steps of impurity removal, blank binding, leaching, water washing, alkali refining, decoloring, molecular distillation, checking and packaging, wherein the molecular distillation step comprises the following three parts: preheating, two-stage distillation and three-stage distillation; the preheating temperature is 150-160 DEG C; the temperature of a heating medium of the two-stage distillation is 165-175 DEG C, the temperature of the heating medium of the three-stage distillation is 185-195 DEG C, both the temperatures of cooling media in the two steps are lower than 40 DEG C, and the vacuum degree of a working cavity of a molecular distiller is 1-5Pa; and the method has the advantages that working procedures of deodorization and dewaxing are not needed, free fatty acid in grease can be effectively removed and the like.

The invention belongs to the technical field of medicine synthesis and discloses a method for synthesizing leconotide. The method comprises the following steps: firstly, carrying out a solid phase coupling method to obtain a linear coarse peptide; and carrying out one-step oxidization according to a liquid phase synthesis method to generate three pairs of disulfide bonds, thus obtaining leconotide. According to the method, Trt is taken as a side chain protective group of Cys; the purity of the linear coarse peptide is improved under the action of a corresponding coupling agent so that the linear coarse peptide is directly used in the next oxidization step without being purified; in addition, by virtue of optimizing a buffering system, an oxidizing agent and pH value in a cyclization reaction, the time of cyclization reaction is effectively shortened and the reaction efficiency is improved.

The invention relates to a method for preparing nano-sized carbon black by lignin at a large scale. The method is characterized by comprising the following steps: purification, oxidization, pre-reaction, condensation, washing, paste preparation and heat treatment. According to the method disclosed by the invention, water serves as a reaction medium, the technological process is simple and controllable, the particle size of a product can be adjusted and controlled by adjusting a high-temperature carbonization technological parameter in the chemical reaction and the heat treatment, and the method is suitable for large-scale industrial production. Additionally, the average particle size of primary particles of the carbon black prepared by the method disclosed by the invention can be 100nm or lower, and the carbon black can be applied to the fields of reinforcement for rubber, plastic filling, and so on.

The invention discloses a method for preparing artificial stone by use of unsaturated polyester paint waste. The method comprises the following steps: uniformly mixing raw materials of the bottom layer, the toughening layer and the surface layer of artificial stone; sequentially pouring, shaping and curing to obtain artificial stone. The bottom layer and the surface layer of the artificial stone comprise the following raw materials in parts by weight: 20-75 parts of unsaturated polyester paint waste powder, 0-35 parts of a flame retardant, 10-20 parts of quartz sand, 10-25 parts of unsaturated polyester resin, 0-3 parts of a curing agent, 0-2 parts of a hindered amine additive, 0-2 parts of a promoter, 0-1 part of a coupling agent A and 0-2 parts of a catalyst A. The artificial stone is wide in application, can serve as indoor artificial stone decorative patterns, kitchen countertops, artificial stone window sills, artificial stone external wall decorative boards and the like, has the advantages of small density, hard texture, good flame retardancy, excellent aging resistance and the like, particularly, has the weight of 1 / 2-1 / 3 of that of ordinary artificial stone under the condition of the same strength, and is convenient to construct and mount.

The invention discloses a zeolite-based positive pole material for a lithium-sulfur battery and preparation and application methods thereof. According to the positive pole material, zeolite is used as a skeleton, and a sulfur-loaded composite material is obtained through infusing elemental sulfur to zeolite and then is wrapped with a conductive substance. According to the zeolite-based positive pole material for the lithium-sulfur battery and the preparation and application methods thereof, through compounding zeolite and sulfur, the dissolution of polysulfide can be effectively reduced, and the volume expansion of sulfur during charging / discharging can be effectively inhibited, so that the cycling performance of the lithium-sulfur battery is improved; due to the wrapping of the conductive substance, the conductivity of the material is enhanced, and the capacity of the lithium-sulfur battery is increased. The preparation process of the positive pole material is simple, and zeolite belongs to a natural environment-friendly material and is low in cost, so that the industrialization of the lithium-sulfur battery is facilitated; meanwhile, due to the introduction of zeolite, the industrial transformation and upgrading of nonmetallic minerals are promoted.

The invention provides a method for preparing an inspection well cover by using an ultra-high-molecular-weight polyethylene composite material. According to the method, an ultra-high-molecular-weight polyethylene composite material waste material which is treated in a solvent is put into a mold corresponding to the inspection well cover in shape, and then is pressed on a flat plate vulcanizing machine under certain temperatures and pressure to prepare the inspection well cover, wherein the ultra-high-molecular-weight polyethylene composite material waste material is leftovers obtained by producing armored protection type products. The preparation method provided by the invention is simple and efficient, has low machining difficulty and no pollution, does not need to separate fibers and resin and has low recycling cost. The performance of the inspection well cover prepared by the method is close to the performance of an inspection well cover prepared by a composite material in the market, so that the inspection well cover has a great price advantage.

The invention provides a TCO (transparent conducting oxide) conducting DBR (distributed Bragg reflector) vertical blue-light LED (light-emitting diode) chip and a manufacturing method thereof. The method comprises the following steps: form a light-emitting epitaxial layer on a sapphire substrate; coating a TCO conducting DBR layer, which is composed of a first-type N-type TCO film and a second-type N-type TCO film and / or nth-type N-type TCO film alternately, on the upper surface of the light-emitting epitaxial layer by vaporization, thereby forming ohmic contact with the upper surface of the light-emitting epitaxial layer; bonding the conducting substrate onto the TCO conducting DBR layer to form a P electrode by a wafer bonding technique; peeling the sapphire substrate by a laser peeling technique; and finally, preparing an N electrode on the lower surface of the light-emitting epitaxial layer. The vertical blue-light LED solves the problems of difficulty in forming ohmic contact with P-GaN, weak reflector adhesiveness, lower reflection factor of the reflector at high temperature, overhigh preparation temperature of the conducting DBR, overhigh voltage of the blue-light LED chip using the conducting DBR as the P electrode, and the like in the vertical LED chip electrode material in the prior art.

The invention discloses low-conductivity and high-temperature direct injection disperse dye ink and a preparation method thereof. The low-conductivity and high-temperature direct injection disperse dye ink is prepared from the following raw materials in parts by mass: 10 to 40 parts of high-temperature disperse dye, 10 to 40 parts of dispersing agent, 10 to 50 parts of organic solvent, 10 to 60 parts of water, 0.05 to 0.5 part of preservative and 0.01 to 0.05 part of defoaming agent, wherein the dispersing agent is a compound product of a special dispersing agent and a nonionic dispersant, andthe weight ratio of the special dispersing agent to the nonionic dispersant is (60 to 95) to (5 to 40). The preparation method comprises the following steps: mixing the high-temperature disperse dye,the dispersing agent, the water, the preservative and the defoaming agent to form a mixture; sanding and dispersing; carrying out nanofiltration on a sanded mixture; adding the organic solvent into obtained color paste, thus obtaining the high-temperature direct injection disperse dye ink. The low-conductivity and high-temperature direct injection disperse dye ink disclosed by the invention has the characteristics of high saturation, bright color and less salt precipitation; the conductivity is low and the service life of a spray head is prolonged; the ink has good dispersion stability and long storage time.

The invention discloses an anti-allergic hair dye and a preparation method thereof, the anti-allergic hair dye comprises the following components by mass percentage concentration: 0.25-3% of oxidationmodified carbon black, 1-5% of high polymer material chitosan, 1-5% of a lemon extract, and the balance of deionized water, and can also comprise 0-2% of a walnut green seedcase extract. The hair dyedisclosed by the invention is simple in components; wherein the oxidation modified carbon black is good in dispersion stability, and other chitosan, the lemon extract and the walnut green seedcase extract components are all natural sources. The prepared hair dye product is safe and non-toxic, tests show that the hair dye product is non-irritant, has no sensitization reaction to skin, is simple inpreparation process, convenient to use and low in cost of oxidation modified carbon black, has greater price advantage compared with other carbon-based black dyeing materials such as carbon nanotubesand graphene, and is suitable for a wide range of people.

The invention provides a method for preparing wear-resistant lining boards by adopting waste materials of an ultra-high molecular weight polyethylene composite material. The method comprises the following steps: placing the waste materials of the ultra-high molecular weight polyethylene composite material treated in a solvent into a specific mould; pressing into the wear-resistant lining boards on a press vulcanizer under the condition of a certain temperature and pressure. The waste materials of the ultra-high molecular weight polyethylene composite material are leftover materials generated when armor protection products are produced. The preparation method is simple, effective, low in processing difficulty, free of pollution and low in recovering cost, and does not need to separate fiber and resin; the performance of the wear-resistant lining boards prepared by adopting the preparation method is similar to that of the conventional ultra-high molecular weight polyethylene wear-resistant lining boards, and the wear-resistant lining boards have a great price advantage.

Disclosed are a construction device for an underground anti-seepage curtain and a construction method. A wall body formed by mutual lap joint of groove sections and grouting or mixing piles is poor incontinuity and not strict in anti-seepage performance, the lap joint process of the piles is complicated, and partial lap joint pile materials are repeated and wasted. The construction device is composed of a sawing and drilling machine and a sawing and drilling rod (17), the lower portion of a driving drill rod (6) on the sawing and drilling machine is in threaded connection with the sawing anddrilling rod, the outer surface of the sawing and drilling rod is annularly provided with a set of cylindrical structures of sawteeth (18) at equal intervals, the sawteeth are arranged counterclockwise and inversely spirally, the distance between every two adjacent sawteeth up and down is 5-15 cm, and the included angle between the sawteeth and the horizontal plane is 30 degrees. The constructiondevice and the construction method are used for the underground anti-seepage curtain.

The invention discloses a PVC / NBR cold-resistant oil-resistant flame retardant thermoplastic elastomer material for a new energy automobile charging pile cable and a preparation method thereof. The elastomer material is prepared from, by weight, 100 parts of polyvinyl chloride resin, 20-40 parts of powder butyronitrile, 30-40 parts of plasticizer A, 20-30 parts of plasticizer B, 20-30 parts of plasticizer C, 5-10 parts of stabilizer, 6-12 parts of flame retardant A, 6-12 parts of flame retardant B, 6-12 parts of flame retardant C, 0.5-1.5 parts of lubricant, 1-2 parts of antioxidant A, 1-2 parts of antioxidant B and 40-70 parts of inorganic filler. The elastomer material is high in mechanical property, good in hydrolysis resistance, strong in oil resistant property and cold resistant property and good in dispersion uniformity and low-temperature flexibility, and therefore the cable is not damaged in multiple times of tow dragging; the PVC / NBR cold-resistant oil-resistant flame retardant thermoplastic elastomer material is good in processing performance, free of particles and smooth in extrusion surface, low in cost, easy to prepare and operate, suitable for occasions on which the elastomer material needs to be frequently bent and scraped at low temperature with oil.

The invention discloses a two-way voice transmission system comprising a node A and a node B, wherein each of the node A and the node B comprises a voice collection module, a voice output module and a core processing module, the voice collection module comprises a microphone and an AD converter, the voice output module comprises a loudspeaker and a DA converter, and the core processing module comprises a wireless transmitting circuit and a wireless receiving circuit. During voice transmission, the microphone of the node A receives a voice signal and transmits the signal to the core processing module after processing the signal through the AD converter, and the wireless transmitting circuit of the core processing module of the node A transmits the signal after AD conversion to the node B; the wireless receiving circuit of the core processing module of the node B receives a wireless signal and outputs the wireless signal to the voice output module of the node B, and the wireless signal is transmitted by the DA converter to the loudspeaker to output voice; and the node B sends the voice to the node A in the same principle so as to accomplish two-way voice transmission. The two-way voice transmission system disclosed by the invention requires no license, and has the advantages of low cost, good safety and good data fluency.

The invention relates to a mechanical cabinet position converter of a gas tank, which belongs to the technical field of measurement. The mechanical cabinet position converter is arranged on a corridorsteel structure of the gas tank; a signal converter arranged on a bracket in a protection cover is connected with the mechanical cabinet position converter through a flexible coupling; and the signalconverter is also connected with a digital-analog converter arranged in an explosion-proof tank through a special explosion-proof cable. The mechanical cabinet position converter of the gas tank adopts a measurement mode of the combination of a coder, the flexible coupling, the bracket, the external digital-analog converter and the explosion-proof tank to convert signals of the mechanical cabinetposition converter of the gas tank so as to convert the signals of the mechanical cabinet position converter into standard 4-20 mA DC signals and send the signals to a basic automatic control system,thereby better monitoring the safe operation of the gas tank. The novel mechanical cabinet position converter not only can be used in dry type gas tanks, but also can be used in Man-type tanks.

A disclosed preparation method for N-methylmorpholine comprises: taking a normal-pressure fixed bed reactor as a reaction apparatus, arranging a supported catalyst in the normal-pressure fixed bed reactor, taking a mixture of morpholine and methyl formate as raw materials, and controlling the molar ratio of methyl formate to morpholine to be 0.5-0.9:1; enabling gasified raw materials to pass through the fixed bed reactor comprising the supported catalyst, so as to perform amination reaction in the presence of hydrogen, and controlling the reaction pressure to be 0.12-0.19 MPa, the temperature to be 120-130 DEG C and the reaction volume space velocity to be 0.05-0.3 g / (h*mL); and after the reaction is finished, condensing and collecting reactants, and performing dewatering and rectification to obtain N-methylmorpholine. The preparation process of the supported catalyst comprises: utilizing a metal salt solution and a carrier to prepare the supported catalyst, wherein the metal accounts for 22%-32% by weight of the whole supported catalyst, and the metal salt is a copper salt or a zinc salt.

The invention belongs to the technical field of poultry feed, and particularly relates to no-soybean meal feed for breeding hens in a egg laying peak period and a preparation method thereof. The no-soybean meal feed for the breeding hens in the egg laying peak period is characterized in that components comprise 20-26% of rapeseed meal, 5-12% of palm kernel meal, 1-3% of soybean oil, 0.3-0.6% of lysine, and 0.5-1% of premix. The feed is made by combining the rapeseed meal with stable quality and no risk of mycotoxin and the palm kernel meal, the soybean meal in the feed for the breeding hens inthe egg laying peak period is completely replaced, and the formula cost is greatly reduced; the dosage of the lysine and fat is increased, the amino acid of diet is balanced and the energy value is increased, and the application effect is ensured; compound enzyme is added to improve the feed utilization rate; and dietary fiber level is improved by the rapeseed meal and the palm kernel meal, and therefore, intestinal health, breeding hens egg production rate, egg quality and reproductive performance are improved.

The invention provides a method for preparing an anti-explosion plate from ultra-high molecular weight polyethylene composite material waste. The method comprises the following steps: putting the ultra-high molecular weight polyethylene composite material waste treated in a solvent into a mold corresponding to the anti-explosion plate in shape; and pressing into the anti-explosion plate on a press vulcanizer at certain temperature and pressure, wherein the ultra-high molecular weight polyethylene composite material waste is a leftover material which is generated when armor protection products are produced. The preparation method provided by the invention is simple, effective, low in processing difficulty, free of pollution, free of fiber and resin separation and low in recovery cost; compared with an anti-explosion plate prepared from a composite material in the market, the anti-explosion plate prepared by adopting the method is not large in difference of property and has the great price advantage.