83 results about "Dynamic elastic modulus" patented technology

A toner is disclosed which is composed of toner particles containing at least a binder resin, a colorant and a wax, and an external additive. The wax has, in its DSC endothermic curve, a maximum endothermic peak at 55° C. to 80° C. within the temperature range from 30° C. to 160° C., the maximum endothermic peak having a half width of from 2° C. to 7° C., and the binder resin is composed chiefly of a polyester resin. The toner has a dynamic elastic modulus from 5×10² to 1×10⁵ dN/m² at 140° C., and its ratio to a dynamic elastic modulus at 170° C. is from 0.05 to 50, and the toner contains 10 to 20% by weight of THF-insoluble matter A of a binder resin component after 8 hours from the start of extraction and 1 to 10% by weight of THF-insoluble matter B of the binder resin component after 24 hours from the start of extraction, the ratio of A to B, B/A, being from 0.1 to 0.8. Also disclosed is a fixing method making use of this toner.

The invention relates to a soil dynamic characteristic test technique for geotechnical engineering and especially relates to a simple instrument and a method for test of an internal stress of a soil mass under cyclic loading. A large quantity of researches and reports record that the roadbed soil under the cyclic loading is suffered from dynamic stress accumulation, but the academics does not pay attention to the phenomenon. The simple instrument can be mainly used for measuring the response conditions of the internal stress in the soil on factors such as different cyclic loading magnitudes, loading waveforms, loading frequencies and soil compaction rate, and acquiring the parameters, such as settlement curve, dynamic elastic modulus, total deformation modulus, static elastic modulus, of the soil mass under the cyclic loading effect. The method provided by the invention belongs to an innovative technology which is simple in laboratory test and convenient in soil dynamic characteristic acquisition; with the help of a lever pressure meter, the instrument can realize 10-times load output and can save instrument consumable materials and power sources; a computer system can be utilized to realize the automatic control on the instrument control and the data collection.

The invention discloses a device and method for testing variation of the early-age dynamic elastic modulus of concrete in a time-dependent manner. The device comprises an excitation tool and test part, a vibration response test part, a signal recording part and a signal processing part, wherein the excitation tool and test part comprise a PVC (Poly Vinyl Chloride) board and a force hammer capable of acting on the PVC board; a rubber hammer is arranged at the front end of the force hammer; a load sensor is arranged on the rubber hammer; the vibration response test part is an acceleration sensor; the acceleration sensor is arranged on the PVC board; the signal recording part is a dynamic signal test and analysis system; and the signal processing part is a computer. The device provided by the invention has the advantages of simple structure, convenience in dismounting and less needed materials and instruments, and belongs to nondestructive test. The device can perform tests repeatedly and continuously, is applicable to both scientific researches and test on the early-age dynamic elastic modulus of concrete in the early age in a construction field.

The invention relates to a method used for measuring the dynamic elastic modulus epsilon and damp ratio xi of woods and wooden compound materials. An acceleration sensor is adopted to convert the inherent mechanical quantity (acceleration) into electric signals and then the data is collected to measure the basic frequency f1 of cantilever beam material with the focused quality after the wave filter and amplification by a signal regulating instrument; the material dynamic elastic modulus epsilon dynamic is figured out in virtue of the defined relation between the material elastic modulus and the basic frequency f1 actually measured by a frequency-domain plot. The amplitudes of A1, A2, ellipsis and An are read out on the time-domain attenuating surge curve in the time-domain plot and then the logarithmic decrement delta and damp ratio xi are respectively figured out. The invention has the advantages that the actual dynamic changes of woods and wooden compound materials can be objectively reflected; the dynamic elastic modulus epsilon and damp ratio xi of woods and wooden compound materials can be simultaneously figured out and the measuring time is short and the data is full, accurate and reliable; and the basic frequency (f1) and damp features can be obtained in the frequency-domain plot and time-domain plot of the measured samples for the relevant analysis.

An active energy ray curable resin composition for a sheet-like optical article capable of providing a cured material having a dynamic elastic modulus at 25° C. of 950 MPa or less and a dynamic elastic modulus at 60° C. of 100 MPa or more and a sheet-like optical article prepared from the resin composition are disclosed. The sheet-like optical article (e.g., prism sheet) has good heat resistance and extremely small warpage.

The invention discloses a method for rapidly detecting parameters of a cement-based material, belonging to the field of civil engineering materials. The method disclosed by the invention is implemented by a bracket of a cement-based material test-piece to be tested, a controllable electromagnet, a small steel ball for shock excitation, an accelerometer for receiving vibration signals, a matched charge amplifier and a signal receiving and acquisition module which are reasonably arranged and matched with data analyzing and processing software. The method comprises the following steps that: the small steel ball freely falls onto the top of the cement-based material test-piece to excite structural vibration of the test-piece; then, the structural vibration is received and collected through the accelerometer and matched equipment and is transmitted to a computer; the computer software can rapidly give parameters, such as dynamic elastic modulus, shear modulus, poisson ratio, transverse wave velocity and longitudinal wave velocity, of the cement-based material to be tested according to a certain algorithm.

A glass crack prevention film-like layer having a glass crack prevention layer exhibiting a dynamic elastic modulus of not larger than 6×10⁶ Pa at 20° C., and an anti-reflection film laminated on one surface of the glass crack prevention layer, while the other surface of the glass crack prevention layer is provided as an adhesive face. A plasma display device having a plasma display panel, and a glass crack prevention film-like layer defined above and directly attached to a visual side of the plasma display panel through the adhesive face of the glass crack prevention layer contained in the glass crack prevention film-like layer.

The invention discloses a rock mass quality classification and dynamic parameter estimation method based on a blasting vibration test. The rock mass quality classification and dynamic parameter estimation method comprises the following steps: distributing test points according to an ordinary blasting vibration test, acquiring the time of a wave P and a wave S for arriving each test point by virtue of a multi-channel data acquisition unit, and also calculating the propagation velocity of the wave P and the wave S between two test points by virtue of a time difference of the wave P and the wave S for arriving the test points and a distance between the test points to ensure that the rock mass quality between the two test points can be judged and a dynamic elastic modulus of a rock mass between the two test points can be calculated according to the propagation velocity. The rock mass quality classification and dynamic parameter estimation method disclosed by the invention is simple to operate, and can be taken as an effective supplement of conventional geological exploration so as to ensure that a lot of time and workload can be saved; and the rock mass quality classification and dynamic parameter estimation method is suitable for the geological exploration of underground cavities in a blasting excavation process, and is also suitable for the geological exploration of side slopes.

The invention provides an evaluation method of freezing resistance of concrete. The method establishes a freezing resistance evaluating indicator relative dynamic elastic modulus evaluation model P(n,t)=(1-kn)[1-alpha<t-4>beta], wherein n is the freezing-thawing circulation frequency; t is single-time freezing-thawing circulation time; k represents the coefficient related to freezing-thawing circulation frequency; and alpha and beta represent the coefficients related to freezing-thawing circulation time. The evaluation model can reflect the concrete freezing resistance level under the combined actions of different freezing-thawing circulation frequencies and different freezing-thawing circulation times, is simple and easy to use and high in accuracy, and has wide application prospects.

The invention discloses a method of estimating dynamic elastic modulus of subgrade soil based on state variable and stress variable. The method includes: using a pressure plate instrument to measure matrix suction of the subgrade soil, and establishing a soil-water characteristic curve to obtain model parameters under different compactness degrees; using a dynamic triaxial instrument to perform dynamic elastic modulus test of subgrade soil to obtain dynamic elastic modulus value of the subgrade soil; establishing a subgrade soil dynamic elastic modulus estimation model based on a state variable and a strain variable; establishing a relational equation between estimation model parameters and subgrade soil physical property indexes. The problem is solved that existing methods of estimating elastic modulus give no consideration to subgrade soil state variable, strain variable, and subgrade soil physical properties.

The invention relates to an anchor agent for screw spikes, comprising cement, sand, fly ash and mixing liquid; in the anchor agent, the cement causes the combination between the anchor agent and walls of sleeper holes to be closer, improves the compressive resistance and flexural strength as well as anti-pulling force in a short time, and meets the construction requirements; the fly ash increases the porosity among each material and enhances density of the material; the durability indexes such as harmful ions erosion resistance, loss resistance of dynamic elastic modulus in freezing and thawing, and rust and corrosion resistance for protecting steel bars are greatly improved, and the service life are prolonged; waterproof agent of polymer concrete, which has good hydrophobic performance to prevent water from entering, does not contain water itself and no conductive irons of free state are formed, thus achieving excellent insulation performance; the anchor agent has the advantages of high early strength, and no temperature environmental affection.

The invention provides a nondestructive testing method for pre-judging long-term durability of concrete in a natural environment. The quality of the long-term durability is represented by forming a concrete test piece under standard curing and natural curing conditions and detecting change of the relative dynamic elastic modulus of concrete under the two curing conditions of different ages. The standard cured test piece is placed back to a curing chamber after age detection, the long-age concrete test piece is transferred along with the movement of the curing chamber according to engineering field conditions, the test pieces are observed continuously and periodically, and a value when the concrete approaches a stable condition at 5y or another age, the corresponding value replaces a test result with longer age; and the naturally cured test piece is placed in the natural environment again after age detection. The dynamic elastic modulus of the test piece of each age under the standard curing condition is taken as the reference, the attenuation value of the relative dynamic elastic modulus of the test piece of each age under the natural curing condition is calculated, and the long-term durability of the concrete is pre-judged.

The invention provides a method for predicting the durability life of concrete based on Birnbaum-Saunders distribution. The method is simple, convenient, high in reliability and wide in application range; the simplicity is reflected in that the service life can be predicted through the method only by detecting to obtain the dynamic elastic modulus value of the concrete; corresponding parameters can be obtained without a large number of experiments; the high reliability is reflected in that the dynamic elastic modulus value is not fitted or mathematical hypothesis is adopted in the life prediction process; the application range is wide, life prediction can be carried out on various concrete service environments including a corrosion environment and freeze-thaw damage and dry-wet cycle environments caused by climate changes, and a series of problems that an existing life prediction technology is narrow in application range, complex in calculation, high in prediction cost and the like aresolved.

The invention discloses a shale cement damage quantitative evaluation method based on an acoustic wave velocity test and relates to the technical field of unconventional oil-gas exploration and development. The method comprises the following steps of drying drilled rock samples, screening out at least three rock samples with similar longitudinal and transverse wave velocities to form a rock sample group, calculating the initial average longitudinal and transverse wave velocity and density of the rock sample group, and calculating an initial dynamic elastic modulus; soaking the rock sample group, taking out the rock sample group every time t, and calculating the water content and the dynamic elastic modulus of the soaked rock sample; calculating a damage variable of the rock sample group; and fitting by adopting a nonlinear fitting method to obtain a shale water content evolution equation and a shale hydration damage evolution equation. According to the method, the influence of rock sample quality change caused by free water invasion on hydration damage is considered, meanwhile, the influence of drilling shaft pressure and shaft temperature is also considered, defects of an existing method are overcome, the shale hydration damage process can be reflected more truly, and the method is simpler, more convenient, more economical and more practical.

In a pneumatic run flat tire in which an inner side reinforcing rubber layer having a falcated cross-section is disposed in a side wall portion, dynamic elastic moduli E′_10A, E′_10B, and E′_10C and values T_10A, T_10B, and T_10C of a tan δ at 60° C. of rubber compositions of each region of the inner side reinforcing rubber layer are configured so as to satisfy the relationships E′_10A<E′_10B<E′_10C, E′_10A≧4.0 MPa, T_10A<T_10B<T_10C, and T_10A≦0.06. Dynamic elastic moduli E′_20A, E′_20B, and E′_20C at 60° C. of rubber compositions of each region of the outer side rubber layer are configured so as to satisfy the relationships E′_20B<E′_20A≦E′_20C and E′_20C/E′_20B≧1.6. Furthermore, the dynamic elastic modulus ratios E′_20A/E′_10A and E′_20C/E′_10C are configured so as to satisfy the relationships 0.6≦E′_20A/E′_10A≦1.0 and 0.6≦E′_20C/E′_10C≦1.0.

The invention provides an online nondestructive detecting instrument for wood materials, which relates to the online nondestructive detection of the wood materials, and can measure the elastic modulus of flitch, board squared timbers and log sections to evaluate the material properties of the materials. The online nondestructive detecting instrument controls a driving and feeding device so that two ends of a tested wood material are clamped by a wood material clamping device. A signal triggering and detecting device can trigger signals and detect transmitted signals and received signals. The transmitted signals and the received signals are amplified by a signal amplifier and then are transmitted to a fast fourier transform (FFT) analyzer to measure the time difference of trigger signals and the received signals, and the dynamic elastic modulus can be calculated by using a formula so as to evaluate the material properties of the tested wood material. The online nondestructive detecting instrument does not destroy the integrity of a tested piece, improves the labor efficiency, reduces the detection cost and lightens the labor intensity.

The utility model discloses a portable dynamic elastic modulus tester controlled by a mobile terminal. The portable dynamic elastic modulus tester comprises a host, a transmitter and a receiver; thehost comprises a broadcasting module, an equipment connecting module, a processor and a lithium ion battery; the host is a cuboid; the broadcast module, the equipment connection module, the processorand the lithium ion battery are arranged in the host, the emitter and the receiver are arranged outside the host, the emitter and the receiver are connected with the host through cables, and the mobile terminals are in one-to-one connection with the equipment connection modules of the tester and perform bidirectional wireless communication through the broadcast module. A user carries a device without a display screen, the carrying weight is reduced, a mobile phone of the user controls and processes data, and the problems that a portable dynamic elasticity modulus tester is limited in information processing capacity, slow in processing and stuck are solved.

The invention relates to a construction project evaluation method, in particular to a slope excavation stability evaluation method. The method comprises the following steps of: acquiring initial dynamic elastic moduli of different depths of an underground high and steep slope before excavation and dynamic elastic moduli in an excavation process; calculating dynamic elastic modulus change values corresponding to different stratum depths, and determining the average damage degree of slope excavation; and establishing a quantitative relationship between the average damage degree and a stability coefficient, and determining the stability coefficient in the slope excavation process. According to the slope excavation stability evaluation method based on dynamic elastic modulus monitoring provided by the invention, the time factor can be considered, the dynamic cause and mechanism of slope instability are coupled, and the defects and limitation of application of a traditional limit equilibrium method and a displacement time sequence method can be effectively overcome.