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The excellent properties of UHSS are achieved by employing common alloying elements (carbon, manganese, silicon, nickel, chromium and molybdenum), micro-alloying (Nb, Ti, V, B) and basic metallurgical strengthening mechanisms such as grain refinement, precipitation hardening, solid solution hardening, transformation hardening and dislocation hardening [9,13].
This phenomenon is related to a number of factors such as the hardness and microstructure of the steel, the magnitude of the tensile residual stress, and the level of diffusible hydrogen in the form of atomic hydrogen that is absorbed into the weld pool during welding [19].
A study using continuous and pulsed current in GTAW of a Ni-Cr-Si based medium carbon UHSS [39] shows that the pulsed mode current results in finer grain size, and smaller martensitic platelets coupled with a reduced tendency for segregation.
MR (martensite), parent material [8] In this comparison, continuous current welds exhibited columnar grain morphology whilst pulse current welds had predominantly equiaxed grain morphology.

Average monthly performance of the sinter plant Indicators The performance value for the period Specific productivity, [t/(m2•h)] 0.93-1.15 / 1.11 The vertical speed of sintering, [mm/min] 17.34-24.01 / 20.32 The content of fine-grained concentrates in the charge, [%] 56.1-69.6 / 62.0 The vacuum in the reservoir, [kPa] 4.74-6.71 / 5.76 The height of the charge layer, [mm] 248-305 / 277.6 The returns content in the charge, [%] 22.5-27.5 / 25.2 The charge temperature, [°C] 40.0-61.0 / 51.6 The carbon content in the charge, [%] 3.27-5.09 / 4.04 Lime consumption, [kg/t] 17.9-30.1 / 28.8 The iron content in the sinter, [%] 50.3-55.4 / 52.7 The sinter basicity for CaO/SiO2, [u] 1.33-1.85 / 1.58 The fines content in the sinter (FR. 0-5 mm), [%] 13.7-17.0 / 15.7 Strength values, [%]: shock 65.0-72.3 / 68.2 abrasion 4.9-5.4 / 5.2 Note: in the numerator – changes interval, in the denominator - the average value.
Despite the limited amount of fine-grained concentrates in the sinter charge, acceptable specific lime consumption (29 kg/t) and the hot return use, the performance indicators of the sinter charge production of the JSC "Ural Steel" are among the lowest in the industry.
This, along with poor technical condition of exhaust gases path, limits the height of the sintered layer, the productivity of the shop and prevents the fine-grained concentrates increase [2 – 4].
Producing a more uniform grain size of the pelletized charge with a minimum amount of fines contributes to the increase of porosity of the sintered layer, and the higher strength of sinter charge pellets allows maintaining high gas permeability during sintering, preventing compaction of the charge under the action of vacuum.
The most significant increase in strength characteristics of the sinter charge was observed if surfactant consumption was 1.6 l/h when the number of the fines formed after flushing was reduced from 10.5 – 11.0 % to 8.5 – 9.5 %.

With the help of SO3 adjustment in cement with DEIPA, a great number of hydro-sulfoaluminates precipitated at the early stage of hydration to decrease the porosity of hardened cement pastes, which contributed to the strength gain of cement.
The BSE image of blank sample shows the typical morphology of Portland cement (Fig. 7a), in which the inner product of C-S-H (also known as high density C-S-H) covers the surfaces of unreacted clinker grains whilst the outer product (alternatively low-density C-S-H) fills in the pores.
In addition, the inner product of C-S-H tends to disappear, being replaced by a small amount of AFm on the boundaries of clinker grains (Fig. 7b), and this is an important feature to differentiate the morphology of blank sample.
In this sample, AFm phase covering the surfaces of unreacted clinker grains is more pronounced, which is rarely reported by the existing literature and deserves further investigation.

Although there are large numbers of medical literature, but penetrates its content to be actually irregular, the literature data lacks has the systematic analysis to make uniform, so that the application value relative reduces largely.
A large number of medical literature knowledge maps Earlier about the build process of a single medical document knowledge map, knowledge maps you want to want to build a large number of medical literature, we start with one of the medical literature knowledge map as the Center, and then look for this medical literature most likely knowledge map, here through literature matrix to identify key words and the knowledge structure of centre of knowledge map is most similar.
Used to identify the most similar knowledge maps of a complex number is: .
This quantitative indicator is s = (N-n)/N, where s is the structure stability of map i, N is the amount of documents represented by the focal map, n is the number of documents which really cause the map’s changes
ESOM using very small numbers as the learning rate to train with the merged document terminology matrix knowledge map.

Introduction As we known, the number of deep & ultra deep- and complex- wells is gradually mounting in onshore oilfield exploiting.
From the difference in polymer concentration contained in the initial solution and the filtrate of cement slurries, the adsorbed amount of polymer on cement grain was calculated.
As adding the polymer amount, the API filtration and permeability of set cement deceased obviously while its adsorbed amount on cement grains would gradually increase.
Further adding the polymer, the permeability of set cement, API filtration of cement slurry and adsorbed amount of PADMO-V @NS on cement grains kept fairly consistent.
c b a Fig.9 SEM images of cement filter cake: (a) net, (b) 0.72% PADMO, (c) 0.72% PADMO-V@NS Fig. 10 Comparative consistency curves of slurry with different filtrate reducer in 210℃ (BHCT) Fig. 11 API filtration, permeability and adsorbed amount of PADMO-V@NS on cement grains (T= 80℃, w/c=0.44) Conclusions A novel polymer/silica nanocomposite used as fluid loss control additive was prepared through an in situ free radical copolymerization.

Indeed, oxidation experiments on Ni-base alloys have demonstrated the occurrence of two different types of base metal damage: penetration of oxygen in the grain boundaries and the formation of a Crdepleted metal layer immediately below the Cr2O3 oxide inner sub-layer as a consequence of the selective oxidation of Cr [1].
Several hypotheses have been proposed to explain this accelerated diffusion, such as the presence of a perturbed layer near the alloy surface that contains small grains and large density of defects [3] or a massive injection of vacancies into the metal caused by the growth of the oxide layer [13-15].
The model EKINOX does not make the classical steady-state hypothesis, and is thus able to study transient stages, evolutions in a finite size substrate due to oxidation and effects of microstructural changes, such as grain growth or dislocation density evolution.
All calculations have been done with an initial number of slabs Ns =132 having a typical initial thickness of 0.25 µm.
This can be done following previous work on a model developed to simulate the irradiation assisted segregation at grain boundaries of austenitic steels [25-26].

A Study of Basic Aluminized Propellants Characteristics 1Amir Aziz and 2Wan Khairuddin Wan Ali Department of Aeronautical EngineeringUniversiti Teknologi Malaysia81310 Skudai, Johor.Malaysia. 1amir3@live.utm.my, 2wankhai@fkm.utm.my Keywords: Aluminized propellant, ammonium perchlorate, burning rate test, pressure exponent, ballistic evaluation motor Abstract :There were very limited number of references published discussing the burning characteristic of aluminized propellant without any additive substance.
Literature search by the author has found that a very limited number of references discussed the characteristics of the propellant without any additive.
The graph in Fig. 7 shows the type of progressive burning which is a similar results reported by Marko V.M. and Vladica S.B.[11] when employing tubular shape propellant grain.

., has been successfully developed to conduct original statistic distribution analysis Figure 1 the Signal draw sketch for single discharge of spark spectrum The relation between intensity ratio of the single discharge of elements derived from each spot and contents of elements at corresponding position can be given by: Ri = Ia,i / Ir,i = K•Ci b R Where, Ri is intensity ratio of number i measurement; Iai and Iri are intensities of analytical and reference lines of number i measurement; Ci is element content of the position corresponding to number i discharge.
D=∑Dj / N Where, Dj is apparent density of the position corresponding to number j discharge; Ci is i element content of the position corresponding to number j discharge； This method can be used in the quantitative analysis of the porosity in the materials. 6.
The sensitivity of the signals is in ratio with grain size of the Inclusion.

Similarly, Fraenkel et al explored the grain drying velocity in the tail pipe of a Rijke-type combustor [4], and found that the oscillating flow gas with a pulsating frequency of 80 Hz and with pulsating amplitude of 1500 Pa can cut down the drying time by half.
Poh et al. adopted computational fluid dynamics to investigate the characteristics of heat transfer in pulsating flow with different Reynolds number (100-1000) and with different oscillating frequency (1-20 Hz) [6], results showed that the best oscillating frequency to enhance heat transfer is different under different Reynolds number.
This finding was supported by Ji et al.’s [7] and Velazquez et al.’s works [8-9], and was extrapolated to a Reynolds number of 10000 by Elshafei et al.’s work [10].
Several works presented the relationship between the heat transfer process inside a pipe and the Prandtl number and the oscillating frequency [11, 12, 13, 14], and developed suitable models to predict the heat transfer process, results showed that there are some proper ranges of Prandtl number and oscillating frequency to enhance heat transfer, otherwise the pulsating flow has no effects on the heat transfer or downgrade the heat transfer coefficient.

In this case, all competing flows have the same max traffic rate calculated as: Bandwidth/Number.
And Bandwidth denotes the client link capacity, Number is the number of storage servers in the cluster system.
We can see that our solution can prevent the Incast collapse when the number of server increases to 128 at least.
When the number of servers increases from 32 to 128, the goodput of our solution decreases slightly from 988Mbps to 878Mbps, while it decreases from 912Mbps to 784Mbps using High Timer solution.
A., Mueller, B.: Safe and effective fine-grained TCP retransmissions for datacenter communication.