Dear Editor,Childhood Disintegrative Disorder(CDD),also known as Heller’s syndrome and disintegrative psychosis,is a rare progressive neurological disorder,characterized by a late onset([2 years of age)and regression...Dear Editor,Childhood Disintegrative Disorder(CDD),also known as Heller’s syndrome and disintegrative psychosis,is a rare progressive neurological disorder,characterized by a late onset([2 years of age)and regression of language,social.展开更多
To examine the difference between early-onset (< age 3) childhood disintegrative disorder (CDD) and autistic disorder with speech loss (ADSL), 8 children with early-onset CDD (mean age = 7.6 years, SD = 3.8;6 males...To examine the difference between early-onset (< age 3) childhood disintegrative disorder (CDD) and autistic disorder with speech loss (ADSL), 8 children with early-onset CDD (mean age = 7.6 years, SD = 3.8;6 males) were compared with 92 age and gender-ratio comparable children with ADSL (mean age = 6.8 years, SD = 4.1;70 males) on 24 variables not directly related to the key features of CDD (regression after normal development for at least the first 2 years after birth). Compared with the ADSL group, the early-onset CDD group had a tendency to have a higher rate of a psychosocial event before speech loss (SL) (early-onset CDD, 75.0% vs ADSL, 37.0%, p = 0.057;effect size (phi) = 0.211, p < 0.05);a significantly higher rate of fearfulness during SL (62.5% vs 4.3%, p = 0.000;phi = 0.551, p < 0.05);and a tendency to have a higher rate of epilepsy (25.0% vs 3.3%, p = 0.050;phi = 0.271, p < 0.05), a tendency to have a lower rate of the Childhood Autism Rating Scale-Tokyo Version (CARS-TV) total score ≥ 30 (75.0% vs 95.7%, p = 0.072;phi = 0.236, p < 0.05), and a significantly lower rate of CARS-TV item 2 (imitation) score ≥ 2 (50.0% vs 82.6%, p = 0.049;phi = 0.221, p < 0.05) on the first visit. The two groups did not exhibit any significant difference in the other 19 variables. The findings of no significant difference in the great majority and a significant difference in the small minority of the 24 variables between the two groups support integrating CDD into regressive autism spectrum disorder and studying CDD as its prototypical form.展开更多
With the legislative development,the organic and inorganic composition separation has become the primary requirement for sewer sediment disposal,however the relevant technology has been rarely reported and the driving...With the legislative development,the organic and inorganic composition separation has become the primary requirement for sewer sediment disposal,however the relevant technology has been rarely reported and the driving mechanism was still unclear.In this study,direct disintegration of biopolymers and indirect broken of connection point were investigated on the hydrolysis and component separation.Three typical sewer sediment treatment approaches,i.e.,alkaline,thermal and cation exchange treatments were proposed,which represented the hydrolysis-driving forces of chemical hydrolysis,physical hydrolysis and innovative cation bridging break-age.The results showed that the organic and inorganic separation rates of sewer sediment driven by alkaline,thermal and cation exchange treatments reached 21.26%,23.80%,and 19.56%-48.0%,respectively,compared to 4.43%in control.The secondary structure of proteins was disrupted,transitioning from𝛼α-helix to𝛽β-turn and random coil.Meanwhile,much biopolymers were released from solid to the liquid phase.From thermody-namic perspective,sewer sediment deposition was controlled by short-range interfacial interactions described by extended Derjaguin-Landau-Verwey-Overbeek theory.Additionally,the separation of organic and inorganic components was positively correlated with the thermodynamic parameters(Corr=0.87),highlighted the robust-ness of various driving forces.And the flocculation energy barriers were 2.40(alkaline),1.60 times(thermal),and 4.02–4.97 times(cation exchange)compared to control group.The findings revealed the contrition differ-ence of direct disintegration of gelatinous biopolymers and indirect breakage of composition connection sites in sediment composition separation,filling the critical gaps in understanding the specific mechanisms of sediment biopolymer disintegration and intermolecular connection breakage.展开更多
To accurately identify the factors affecting the formation of stable aggregates in bauxite residue during the soil formation process,the comprehensive effects of a combined chemical-biological amelioration strategy in...To accurately identify the factors affecting the formation of stable aggregates in bauxite residue during the soil formation process,the comprehensive effects of a combined chemical-biological amelioration strategy including solid wastes and a functional microorganism on aggregate size distribution and its stability in bauxite residue were investigated during a 365-d simulation experiment.The results showed that the combined amelioration effectively reduced the saline alkalinity of bauxite residue,and markedly changed the contents of aggregate-associated chemical binding agents.Desulfurization gypsum and maize straw-Penicillium oxalicum(P.oxalicum)differentiated the formation of aggregates within different sizes.Maize straw-P.oxalicum stimulated the formation of water-stable macroaggregates with more durable erosion resistance by the wet-sieving and laser dynamic diffraction analysis.The Pearson correlation analysis showed that exchangeable polyvalent metal ions,pyrophosphate extractable Fe oxide,and organic carbon exhibited positive correlations with aggregate stability during the 365-d incubation.The findings in this study may provide data support and engineering practical reference for ecological restoration in the disposal areas.展开更多
Loess slopes in cold and arid regions are susceptible to shallow soil degradation,which may trigger severe environmental problems related to soil erosion.To address this environmental challenge,this study selected a c...Loess slopes in cold and arid regions are susceptible to shallow soil degradation,which may trigger severe environmental problems related to soil erosion.To address this environmental challenge,this study selected a compound ecological curing agent composed of gellan gum and guar gum for stabilizing shallow loess slopes.Triaxial compression and disintegration tests were employed to comparatively analyze the effects of compound gum content,mass mix ratio,and curing age on the mechanical and disintegration properties of solidified loess.The curing mechanism was analyzed using scanning electron microscopy(SEM),and the ecological protection effect was monitored for a 60-day period.The results indicate that gellan gum,guar gum,and the compound gum can enhance the mechanical and disintegration properties of loess,promote plant growth,and optimize the ecological environment.However,the combination of gellan gum and guar gum proves more effective than using either gellan gum or guar gum alone.Considering the effects on mechanical properties,disintegration performance,and material economy,the disintegration rate of loess decreases by 75.72%compared to plain loess when the compound glue content is 0.5%,the mixing ratio of gellan gum to guar gum is 3:7 and the curing age is 7 days.Meanwhile,the cohesion and internal friction angle increase by 118.06%and 10.97%,respectively.Moreover,the disintegration performance and mechanical properties of the samples first increase and then decrease with the increase in compound glue and the mix ratio and are basically stabilized after the curing age reaches 7d.展开更多
Cyclic wetting-drying alternation has a significant influence on the strength and structure of soils.It is prone to causing soil softening and disintegration,highlighting the importance to improve the soil's resis...Cyclic wetting-drying alternation has a significant influence on the strength and structure of soils.It is prone to causing soil softening and disintegration,highlighting the importance to improve the soil's resistance to disintegration.This paper utilizes a self-developed disintegration test apparatus to analyze the disintegration characteristics of improved red soil under wet-dry cycles,focusing on the disintegration amount and ratio.Furthermore,XRD(X-ray diffraction),SEM(scanning electron microscope),tensile test,and contact angle test are employed to investigate the anti-disintegration behaviors of the improved red soil.The results show that the disintegrating amount and ratio of undisturbed and improved red soil are distinctly different under wet-dry cycles.Linear,stepped,constant and concave but perfect"S"shapes of the disintegrating ratio are observed in the cyclic tests.Cement and lime strengthen the red soil primarily through hydration reaction.The drop experiment confirms that cement plays a crucial role in restraining the disintegration.When the ameliorant content is low,the correlation between pore parameters and disintegration duration of red soil follows the order:mean shape coefficient>fractal dimension>probability entropy>area probability distribution index.With a high ameliorant content,the correlation remains similar,with slightly higher correlation for probability entropy.Under wet-dry cycle conditions,sludge and kaolin can improve the soil through the bonding of clay particles.The improved water repellency greatly enhances the resistance to disintegration of the altered red soil.The research provides valuable insights for the practical application of soil.展开更多
Sulfur-free lignin(SFL),a byproduct of the corn ethanol industry,effectively improves soil strength;however,its inherent solubility limits saline soil treatment in dry-wet environments.To solve this problem,this paper...Sulfur-free lignin(SFL),a byproduct of the corn ethanol industry,effectively improves soil strength;however,its inherent solubility limits saline soil treatment in dry-wet environments.To solve this problem,this paper proposes the selection of a granular SFL(GSFL)with a relatively large particle size,but with its chemical properties retained,to replace the conventional powdered SFL(PSFL).Among the processes of water-induced erosion failure of earthen structures,disintegration is commonly deemed the primary cause.Therefore,the disintegration characteristics of both PSFL-and GSFL-modified soils with 0%,5%,7%,10%,and 12%dosages were tested under dry-wet conditions.Moreover,several physicochemical properties,including the particle size distribution,bound water content,pH value,cation exchange capacity,functional groups,and microstructure,were explored.The results revealed that the water stability of the GSFL-modified soils was greater than that of the PSFL-modified soils.All of the PSFL-modified soils and natural soil completely disintegrated at the first immersion stage,whereas the GSFL-modified soils resisted 7 dry-wet cycles,notably at the 10%dosage.Microscopic analysis revealed that the SFL particle size affected mainly the cementation strength and microstructural homogeneity.Both the GSFL and PSFL particles strengthened the intergranular cementation through ion exchange,electrostatic interactions,and reinforcement effects.However,the PSFL preferentially filled the intragranular pores,causing a nonuniform microstructural arrangement and ineffectively enhancing the disintegration resistance of the saline soil.This preliminary study suggests that the particle size of a soil modifier may affect certain properties of the modified soil,necessitating future focused research.展开更多
It is an important way to realize low carbon in China’s iron and steel industry by hydrogen-rich blast furnace smelting process.Sinter is the main blast furnace burden,and its reduction characteristics have a signifi...It is an important way to realize low carbon in China’s iron and steel industry by hydrogen-rich blast furnace smelting process.Sinter is the main blast furnace burden,and its reduction characteristics have a significant influence on ironmaking.The reduction behaviors,including reduction index(RI)and low-temperature reduction disintegration index(RDI),and the reduction mechanism of sinter in hydrogen-rich blast furnace were investigated.The results show that RI increased from 82.85 to 95.53 wt.%with an increase in H_(2)content from 0 to 30 vol.%,and the main phase of the reduction product was metallic iron.In the research of RDI,when the H_(2)content was increased from 0 to 20 vol.%,RDI+3.15 increased from 69.61 to 75.38 wt.%,and the main reaction was the reduction of hematite to magnetite.At 600-950℃,the reduction of sinter in CO and hydrogen-rich atmospheres(H_(2):CO=2)was both controlled by the first-order reaction model,and the apparent activation energy was 33.64 and 44.57 kJ/mol,respectively.展开更多
Disintegrated dolomite slope and tunnel disasters occur frequently due to poor water stability of disintegrated dolomite,primarily in a form of seepage failure.For engineering purposes,it is critical to determine the ...Disintegrated dolomite slope and tunnel disasters occur frequently due to poor water stability of disintegrated dolomite,primarily in a form of seepage failure.For engineering purposes,it is critical to determine the seepage properties of disintegrated dolomite within the strata.However,conventional experimental methods are time-consuming and expensive and may not be effective in investigating seepage characteristics due to the heterogeneity of disintegrated dolomite.In this study,pore network model(PNM)was established by the computerized tomography(CT)scanning technology to characterize the pores.Meanwhile,the seepage and coefficient of permeability under different inlet stress conditions based on the accurate pore model were realized by linking the commercial image processing software Avizo with the commercial multi-physics modeling package Comsol.The results show that the porosities of severely and completely disintegrated dolomites are 29.17% and 45.37%,respectively.The grade of pore development increases with disintegration grade,which facilitates seepage failure.Severely and completely disintegrated dolomites have the coefficients of permeability of 9.67×10^(-7) m/s and 1.61×10^(-6) m/s,respectively.Under conventional conditions,severely and completely disintegrated dolomites undergo seepage failure above a pressure difference of 6×10^(3) Pa and 5×10^(3) Pa,respectively.These results are consistent with both in situ water pressure tests in the borehole and laboratory tests with the constant-head method,demonstrating that CT scanning is an effective method for observing fractures and pores in disintegrated dolomite for seepage evaluation.展开更多
The rapid development of military technology has prompted different types of equipment to break the limits of operational domains and emerged through complex interactions to form a vast combat system of systems(CSoS),...The rapid development of military technology has prompted different types of equipment to break the limits of operational domains and emerged through complex interactions to form a vast combat system of systems(CSoS),which can be abstracted as a heterogeneous combat network(HCN).It is of great military significance to study the disintegration strategy of combat networks to achieve the breakdown of the enemy’s CSoS.To this end,this paper proposes an integrated framework called HCN disintegration based on double deep Q-learning(HCN-DDQL).Firstly,the enemy’s CSoS is abstracted as an HCN,and an evaluation index based on the capability and attack costs of nodes is proposed.Meanwhile,a mathematical optimization model for HCN disintegration is established.Secondly,the learning environment and double deep Q-network model of HCN-DDQL are established to train the HCN’s disintegration strategy.Then,based on the learned HCN-DDQL model,an algorithm for calculating the HCN’s optimal disintegration strategy under different states is proposed.Finally,a case study is used to demonstrate the reliability and effectiveness of HCNDDQL,and the results demonstrate that HCN-DDQL can disintegrate HCNs more effectively than baseline methods.展开更多
The oral disintegrating film(ODF)offers significant advantages such as superior patient compliance and rapid action onset as a form of solid drug delivery.However,the drug loading efficiency and dosage of the ODF curr...The oral disintegrating film(ODF)offers significant advantages such as superior patient compliance and rapid action onset as a form of solid drug delivery.However,the drug loading efficiency and dosage of the ODF currently available in the market are limited.To enhance the drug loading efficiency,with bacterial cellulose(BC)and hyaluronic acid(HA)as film-forming agents,glycerol(GL)as a plasticizer,and diprophylline(Dilor)as the model drug,a Dilor-ODF was prepared by a solvent casting method for the treatment of acute asthma-related diseases.The BC nano-network structure was utilized to augment the drug loading efficiency of the Dilor-ODF,while HA and GL were used to improve the elongation at break.The disintegration time,drug loading efficiency and drug releasing rate,and tensile properties of the Dilor-ODF were mainly evaluated.The results indicated that the Dilor-ODF exhibited a smooth surface with a uniform thickness and a maximum drug loading efficiency of(51.10±0.08)%.The time for complete disintegration and that for drug release in simulated oral saliva were less than 30 and 90 s,respectively,indicating the effect of rapid release.The tensile strength and elongation at break of the Dilor-ODF were(46.3±2.8)MPa and(1.9±0.2)%,respectively.The thermal decomposition temperature of the Dilor-ODF was higher than 200℃,satisfying subsequent processing demand.展开更多
In gas injection refining processes,wide dispersion of small bubbles in the bath is indispensable for high refining efficiency.Eccentric mechanical stirring with unidirectional impeller rotation was tested using a wat...In gas injection refining processes,wide dispersion of small bubbles in the bath is indispensable for high refining efficiency.Eccentric mechanical stirring with unidirectional impeller rotation was tested using a water model for pursuing better bubble disintegration and dispersion.Effects of various factors on bubble disintegration and dispersion were investigated.These factors were stirring mode,eccentricity and rotation speed,nozzle structure,nozzle immersion depth,and gas flow rate.Gas injection from a nozzle at the end of the impeller shaft and from an immersed lance was studied.Under eccentric stirring,a vortex was formed away from the shaft.Small bubbles were produced in the strong turbulence or high shear stress field near the rotating impeller and moved in the direction to the vortex keeping up with the macroscopic flow induced by the mechanical stirring.Thus small bubbles could disperse widely in the bath under eccentric stirring with unidirectional rotation.展开更多
Ahn To develop a high resolution HPLC method for the determination of ondansetron in human plasma and to study the pharmacokinetics of ondansetron in orally disintegrating tablets. Methods HPLC determination involved ...Ahn To develop a high resolution HPLC method for the determination of ondansetron in human plasma and to study the pharmacokinetics of ondansetron in orally disintegrating tablets. Methods HPLC determination involved liquid-liquid extraction, separation on a CN column and ultraviolet detection at 310 ran with granisetron as an internal standard. Pharmacokinetics and bioequivalence of ondansetron in orally disintegrating tablets by direct compression and conventional 8 mg tablets were evaluated and compared in 20 healthy human male volunteers after a single oral dose in a randomized cross-over study. Results The limit of quantification was 0.25 ng· mL^-1. The recovery was about 85 % or over for ondan setron and about 90% for internal standard. Linearity was good within the concentration range of 0.5 - 50 ng·mL^-1 with r^2 ranging from 0.997 1 to 0.999 9. Intra- and inter-assay coefficients of variation ranged from 1.78% to 2.38% and 3.88% -5.19%, respectively. Accuracies for spiked concentrations of 2.0, 10.0, and 30.0 ng·mL^-1 were 104.7% ±4.4%, 102.2% ± 1.1%, and99.51% ±2.34%, respectively. Pharmacokinetic parameters of AUCo-t, AUCo-∞ , Cmax, Tmax, and T1/2 were 230.2 ± 78.0 ng·h·L^-1 , 265.2± 101.5 ng·h·mL^-1, 35.67 ± 8.94 ng·mL^-l, 1.51 ±0.79 h, and 5.00± 1.41 h for orally disintegrating tablets, respectively. The analysis of variance did not show any significant difference between orally disintegrating tablets and conventional tablets, and 90% confidence intervals fell within the acceptable range for bioequivalence. Conclusion High resolution HPLC method has been set up and applied in pharmacokinetic evaluation of ondansetron in orally disintegrating tablets.展开更多
Aim The aim of the present study was to prepare tablets which can rapidlydisintegrate in saliva, containing active ingredient in high dose (37.5% W/W). Methods Rapidlydisintegrating tablets containing rotundine were p...Aim The aim of the present study was to prepare tablets which can rapidlydisintegrate in saliva, containing active ingredient in high dose (37.5% W/W). Methods Rapidlydisintegrating tablets containing rotundine were prepared by direct compression, wet granulation andmoulding, respectively . Different disintegrants and excipients were decided by single factor test.The typical disintegration time measurement and a new method of wetting time measuring wereintroduced for assessing rapidly disintegrating tablets. Results The tablets (80 mg) prepared bydirect compression have the crushing strength of 4.0 kg ?mm^(-2) and rapidly disintegratewithin 15 s in the saliva of healthy volunteers; the tablets prepared by wet granulation also havesufficient strength, a little longer but acceptable disintegration time (within 25 s in saliva) ;and the tablets obtained by moulding show disintegration within 40 s in saliva but low strength (2kg·mm^(-2)) . Disintegration time profiles of tablets are similar to those of wetting time, and thedisintegration and wetting times in vitro are similar to the disintegration time in vivo, thelatter having higher correlation with that in oral cavity. Conclusion The rapidly disintegratingtablets can be prepared by using these three techniques and excipients. Both in vitro disintegrationtime and wetting time are necessary indexes for judgment of in vitro disintegration profile.展开更多
BACKGROUND Late infantile ceroid lipofuscinosis is a rare neurodegenerative disorder that appears between the ages of 2 and 4 years and is difficult to diagnose. In this report we present two sisters with this conditi...BACKGROUND Late infantile ceroid lipofuscinosis is a rare neurodegenerative disorder that appears between the ages of 2 and 4 years and is difficult to diagnose. In this report we present two sisters with this condition, and the clinical course consisted of delayed developmental skills initially and later regression of previously acquired skills. The cases were initially considered as childhood disintegrative disorder(CDD); however, when whole exome sequencing(WES) genetic testing was done, they proved to be variant late infantile ceroid lipofuscinosis. This is the first report from Jordan.CASE SUMMARY Clinical presentation included developmental delay and initially speech delay,followed by lose of sphincter control. Motor development was normal until 4 years of age, then they developed ataxia(fear of going downstairs) and weakness while walking. Atonic and myoclonic seizures become intractable, and this was followed by inability to stand or sit and loss of expressive language. In addition to complete blood count test, liver function test, kidney function test, serum electrolyte test, and blood sugar test, serum amino acid profile, B12 level test,thyroid function test, and a brain computed tomography scan were also normal.An electroencephalogram showed a generalized spike and wave pattern, and magnetic resonance imaging showed little to no abnormalities. After dealing with the cases as CDD, WES testing proved a final diagnosis of variant late infantile ceroid lipofuscinosis. Current treatment is anti-epileptic drugs and supportive care at home, and they are now in vegetative state.CONCLUSION This report highlights the importance of WES for the identification of genetic diseases, especially neurodegenerative disorders.展开更多
The disintegration of granite residual soil is especially affected by variations in physical and chemical properties. Serious geologic hazards or engineering problems are closely related to the disintegration of grani...The disintegration of granite residual soil is especially affected by variations in physical and chemical properties. Serious geologic hazards or engineering problems are closely related to the disintegration of granite residual soil in certain areas. Research on the mechanical properties and controlling mechanisms of disintegration has become a hot issue in practical engineering. In this paper, the disintegration characteristics of improved granite residual soil are studied by using a wet and dry cycle disintegration instrument, and the improvement mechanism is analyzed. The results show that the disintegration amounts and disintegration ratios of soil samples treated with different curing agents are obviously different. The disintegration process of improved granite residual soil can be roughly divided into 5 stages:the forcible water intrusion stage, microcrack and fissure development stage, curing and strengthening stage, stable stage, and sudden disintegration stage. The disintegration of granite residual soil is caused by the weakening of the cementation between soil particles under the action of water. When the disintegration force is greater than the anti-disintegration force of soil, the soil will disintegrate. Cement and lime mainly rely on ion exchange agglomeration, the inclusion effect of curing agents on soil particles, the hard coagulation reaction and carbonation to strengthen granite residual soil. Kaolinite mainly depends on the reversibility of its own cementation to improve and strengthen granite residual soil. The reversibility of kaolinite cementation is verified by investigating pure kaolinite with a tensile, soaking, drying and tensile test cycle. Research on the disintegration characteristics and disintegration mechanism of improved granite residual soil is of certain reference value for soil modification.展开更多
Size and quantity of fractured zone and non-fractured zone are controlled by cracks contained in deep rock masses. Zonal disintegration mechanism is strongly dependent on the interaction among cracks. The strong inter...Size and quantity of fractured zone and non-fractured zone are controlled by cracks contained in deep rock masses. Zonal disintegration mechanism is strongly dependent on the interaction among cracks. The strong interaction among cracks is investigated using stress superposition principle and the Chebyshev polynomials expansion of the pseudo-traction. It is found from numerical results that crack nucleation, growth and coalescence lead to failure of deep crack- weakened rock masses. The stress redistribution around the surrounding rock mass induced by unloading excavation is studied. The effect of the excavation time on nucleation, growth, interaction and coalescence of cracks was analyzed. Moreover, the influence of the excavation time on the size and quantity of fractured zone and non-fractured zone was given. When the excavation time is short, zonal disintegration phenomenon may occur in deep rock masses. It is shown from numerical results that the size and quantity of fractured zone increase with decreasing excavation time, and the size and quantity of fractured zone increase with the increasing value of in-situ geostress.展开更多
Complex systems widely exist in nature and human society.There are complex interactions between system elements in a complex system,and systems show complex features at the macro level,such as emergence,self-organizat...Complex systems widely exist in nature and human society.There are complex interactions between system elements in a complex system,and systems show complex features at the macro level,such as emergence,self-organization,uncertainty,and dynamics.These complex features make it difficult to understand the internal operation mechanism of complex systems.Networked modeling of complex systems is a favorable means of understanding complex systems.It not only represents complex interactions but also reflects essential attributes of complex systems.This paper summarizes the research progress of complex systems modeling and analysis from the perspective of network science,including networked modeling,vital node analysis,network invulnerability analysis,network disintegration analysis,resilience analysis,complex network link prediction,and the attacker-defender game in complex networks.In addition,this paper presents some points of view on the trend and focus of future research on network analysis of complex systems.展开更多
Hydrogen-enrich iron making process is certainly to be an effective method to reduce greenhouse gases emission.However,the effect of hydrogen addition on the low temperature metallurgical property of sinter is still u...Hydrogen-enrich iron making process is certainly to be an effective method to reduce greenhouse gases emission.However,the effect of hydrogen addition on the low temperature metallurgical property of sinter is still unclear.A detailed investigation was performed on the above topic.The results are as follows.When CO is partially replaced by H2,the RDI〈3.15（RDI〈2.8） of sinter decreases with the increase of the H2 content;when the content of H2 increases,the CO,CO2 and N2 decrease proportionally,in this case,RDI〈3.15（RDI〈2.8） of sinter increases with the increase of H2 content;the value of RDI〈3.15（RDI〈2.8） basically depends on the reduction index（Ri）.The experimental data of RDI〈2.8 based on Japanese industrial standard（JIS） are a little higher than the data of RDI〈3.15 based on Chinese industrial standard（CIS） in the same condition.In addition,for part of CO is replaced by H2：RDI〈2.8=3.38394＋1.1585 RDI〈3.15;for other gases,except H2,are decreased proportionally：RDI〈2.8=17.39678＋0.42922 RDI〈3.15展开更多
Rock masses without pre-existing macrocracks can usually be considered as granular materials with only microcracks.During the excavation of the tunnels,microcracks may nucleate,grow and propagate through the rock matr...Rock masses without pre-existing macrocracks can usually be considered as granular materials with only microcracks.During the excavation of the tunnels,microcracks may nucleate,grow and propagate through the rock matrix;secondary microcracks may appear,and discontinuous and incompatible deformation of rock masses may occur.The classical continuum elastoplastic theory is not suitable for analyzing discontinuous and incompatible deformation of rock masses.Based on non-Euclidean model of the discontinuous and incompatible deformation of rock masses,the distribution of stresses in the surrounding rock masses in deep tunnels is fluctuant or wave-like.The stress concentration at the tips of microcracks located in vicinity of stress wave crest is comparatively large,which may lead to the unstable growth and coalescence of secondary microcracks,and consequently the occurrence of fractured zones.On the other hand,the stress concentration at the tips of microcracks located around stress wave trough is relatively small,which may lead to the arrest of microcracks,and thus the non-fractured zones.The alternate appearance of stress wave crest and trough thus may induce the alternate occurrence of fractured and non-fractured zones in deep rock masses.For brittle rocks,the dissipated energy of microcrack growth is small,but the elastic strain energy stored in rock masses may be larger than the dissipated energy growths of pre-existing microcracks and secondary microcracks.The sudden release of the residual elastic strain energy may lead to rockburst.Based on this understanding,the criteria of rockburst are established.Furthermore,the relationship between rockbursts and zonal disintegration in the surrounding rock masses around deep tunnels is studied.The influences of the in-situ stresses and the physico-mechanical parameters on the distribution of rockburst zones and the ejection velocity of rock fragments are investigated in detail.展开更多
基金supported by the Chinese Academy of Sciences Strategic Priority Research Program,China(XDB02050400)the National Natural Science Foundation of China(91432111)the Shanghai Second Medical University-Institute of Neuroscience Research Center for Brain Disorders,China(2015NKX005)
文摘Dear Editor,Childhood Disintegrative Disorder(CDD),also known as Heller’s syndrome and disintegrative psychosis,is a rare progressive neurological disorder,characterized by a late onset([2 years of age)and regression of language,social.
文摘To examine the difference between early-onset (< age 3) childhood disintegrative disorder (CDD) and autistic disorder with speech loss (ADSL), 8 children with early-onset CDD (mean age = 7.6 years, SD = 3.8;6 males) were compared with 92 age and gender-ratio comparable children with ADSL (mean age = 6.8 years, SD = 4.1;70 males) on 24 variables not directly related to the key features of CDD (regression after normal development for at least the first 2 years after birth). Compared with the ADSL group, the early-onset CDD group had a tendency to have a higher rate of a psychosocial event before speech loss (SL) (early-onset CDD, 75.0% vs ADSL, 37.0%, p = 0.057;effect size (phi) = 0.211, p < 0.05);a significantly higher rate of fearfulness during SL (62.5% vs 4.3%, p = 0.000;phi = 0.551, p < 0.05);and a tendency to have a higher rate of epilepsy (25.0% vs 3.3%, p = 0.050;phi = 0.271, p < 0.05), a tendency to have a lower rate of the Childhood Autism Rating Scale-Tokyo Version (CARS-TV) total score ≥ 30 (75.0% vs 95.7%, p = 0.072;phi = 0.236, p < 0.05), and a significantly lower rate of CARS-TV item 2 (imitation) score ≥ 2 (50.0% vs 82.6%, p = 0.049;phi = 0.221, p < 0.05) on the first visit. The two groups did not exhibit any significant difference in the other 19 variables. The findings of no significant difference in the great majority and a significant difference in the small minority of the 24 variables between the two groups support integrating CDD into regressive autism spectrum disorder and studying CDD as its prototypical form.
基金supported by Shaanxi Key Research and Development Program(No.2024SF-YBXM-546)the National Natural Science Foundation of China(No.52470161)the State Key Laboratory of Pollution Control and Resource Reuse Foundation(No.PCRRF21007).
文摘With the legislative development,the organic and inorganic composition separation has become the primary requirement for sewer sediment disposal,however the relevant technology has been rarely reported and the driving mechanism was still unclear.In this study,direct disintegration of biopolymers and indirect broken of connection point were investigated on the hydrolysis and component separation.Three typical sewer sediment treatment approaches,i.e.,alkaline,thermal and cation exchange treatments were proposed,which represented the hydrolysis-driving forces of chemical hydrolysis,physical hydrolysis and innovative cation bridging break-age.The results showed that the organic and inorganic separation rates of sewer sediment driven by alkaline,thermal and cation exchange treatments reached 21.26%,23.80%,and 19.56%-48.0%,respectively,compared to 4.43%in control.The secondary structure of proteins was disrupted,transitioning from𝛼α-helix to𝛽β-turn and random coil.Meanwhile,much biopolymers were released from solid to the liquid phase.From thermody-namic perspective,sewer sediment deposition was controlled by short-range interfacial interactions described by extended Derjaguin-Landau-Verwey-Overbeek theory.Additionally,the separation of organic and inorganic components was positively correlated with the thermodynamic parameters(Corr=0.87),highlighted the robust-ness of various driving forces.And the flocculation energy barriers were 2.40(alkaline),1.60 times(thermal),and 4.02–4.97 times(cation exchange)compared to control group.The findings revealed the contrition differ-ence of direct disintegration of gelatinous biopolymers and indirect breakage of composition connection sites in sediment composition separation,filling the critical gaps in understanding the specific mechanisms of sediment biopolymer disintegration and intermolecular connection breakage.
基金Projects(42177391,42477437)supported by the National Natural Science Foundation of ChinaProject(2024RC3041)supported by the Science and Technology Innovation Program of Hunan Province,China+1 种基金Project(2023CXQD064)supported by the Innovation-Driven Research Programme of Central South University,ChinaProject(242102321124)supported by the Henan Provincal Science and Technology Research Project,China。
文摘To accurately identify the factors affecting the formation of stable aggregates in bauxite residue during the soil formation process,the comprehensive effects of a combined chemical-biological amelioration strategy including solid wastes and a functional microorganism on aggregate size distribution and its stability in bauxite residue were investigated during a 365-d simulation experiment.The results showed that the combined amelioration effectively reduced the saline alkalinity of bauxite residue,and markedly changed the contents of aggregate-associated chemical binding agents.Desulfurization gypsum and maize straw-Penicillium oxalicum(P.oxalicum)differentiated the formation of aggregates within different sizes.Maize straw-P.oxalicum stimulated the formation of water-stable macroaggregates with more durable erosion resistance by the wet-sieving and laser dynamic diffraction analysis.The Pearson correlation analysis showed that exchangeable polyvalent metal ions,pyrophosphate extractable Fe oxide,and organic carbon exhibited positive correlations with aggregate stability during the 365-d incubation.The findings in this study may provide data support and engineering practical reference for ecological restoration in the disposal areas.
基金funded by the Natural Science Foundation of Inner Mongolia Autonomous Region(2023JQ03,2023QN05014)the Youth Science and Technology Talents Project of Autonomous Region Colleges and Universities(NJYT22108)。
文摘Loess slopes in cold and arid regions are susceptible to shallow soil degradation,which may trigger severe environmental problems related to soil erosion.To address this environmental challenge,this study selected a compound ecological curing agent composed of gellan gum and guar gum for stabilizing shallow loess slopes.Triaxial compression and disintegration tests were employed to comparatively analyze the effects of compound gum content,mass mix ratio,and curing age on the mechanical and disintegration properties of solidified loess.The curing mechanism was analyzed using scanning electron microscopy(SEM),and the ecological protection effect was monitored for a 60-day period.The results indicate that gellan gum,guar gum,and the compound gum can enhance the mechanical and disintegration properties of loess,promote plant growth,and optimize the ecological environment.However,the combination of gellan gum and guar gum proves more effective than using either gellan gum or guar gum alone.Considering the effects on mechanical properties,disintegration performance,and material economy,the disintegration rate of loess decreases by 75.72%compared to plain loess when the compound glue content is 0.5%,the mixing ratio of gellan gum to guar gum is 3:7 and the curing age is 7 days.Meanwhile,the cohesion and internal friction angle increase by 118.06%and 10.97%,respectively.Moreover,the disintegration performance and mechanical properties of the samples first increase and then decrease with the increase in compound glue and the mix ratio and are basically stabilized after the curing age reaches 7d.
基金financially supported by the National Natural Science Foundation of China(Grant No.42102303)the Natural Science Foundation of Yunnan Province,China(Grant No.202401CF070174)the Xingdian Talent Support Program(Grant No.C619300A130).
文摘Cyclic wetting-drying alternation has a significant influence on the strength and structure of soils.It is prone to causing soil softening and disintegration,highlighting the importance to improve the soil's resistance to disintegration.This paper utilizes a self-developed disintegration test apparatus to analyze the disintegration characteristics of improved red soil under wet-dry cycles,focusing on the disintegration amount and ratio.Furthermore,XRD(X-ray diffraction),SEM(scanning electron microscope),tensile test,and contact angle test are employed to investigate the anti-disintegration behaviors of the improved red soil.The results show that the disintegrating amount and ratio of undisturbed and improved red soil are distinctly different under wet-dry cycles.Linear,stepped,constant and concave but perfect"S"shapes of the disintegrating ratio are observed in the cyclic tests.Cement and lime strengthen the red soil primarily through hydration reaction.The drop experiment confirms that cement plays a crucial role in restraining the disintegration.When the ameliorant content is low,the correlation between pore parameters and disintegration duration of red soil follows the order:mean shape coefficient>fractal dimension>probability entropy>area probability distribution index.With a high ameliorant content,the correlation remains similar,with slightly higher correlation for probability entropy.Under wet-dry cycle conditions,sludge and kaolin can improve the soil through the bonding of clay particles.The improved water repellency greatly enhances the resistance to disintegration of the altered red soil.The research provides valuable insights for the practical application of soil.
基金funded by the National Natural Science Foundation of China(Grant Nos.42330708 and 42302329).
文摘Sulfur-free lignin(SFL),a byproduct of the corn ethanol industry,effectively improves soil strength;however,its inherent solubility limits saline soil treatment in dry-wet environments.To solve this problem,this paper proposes the selection of a granular SFL(GSFL)with a relatively large particle size,but with its chemical properties retained,to replace the conventional powdered SFL(PSFL).Among the processes of water-induced erosion failure of earthen structures,disintegration is commonly deemed the primary cause.Therefore,the disintegration characteristics of both PSFL-and GSFL-modified soils with 0%,5%,7%,10%,and 12%dosages were tested under dry-wet conditions.Moreover,several physicochemical properties,including the particle size distribution,bound water content,pH value,cation exchange capacity,functional groups,and microstructure,were explored.The results revealed that the water stability of the GSFL-modified soils was greater than that of the PSFL-modified soils.All of the PSFL-modified soils and natural soil completely disintegrated at the first immersion stage,whereas the GSFL-modified soils resisted 7 dry-wet cycles,notably at the 10%dosage.Microscopic analysis revealed that the SFL particle size affected mainly the cementation strength and microstructural homogeneity.Both the GSFL and PSFL particles strengthened the intergranular cementation through ion exchange,electrostatic interactions,and reinforcement effects.However,the PSFL preferentially filled the intragranular pores,causing a nonuniform microstructural arrangement and ineffectively enhancing the disintegration resistance of the saline soil.This preliminary study suggests that the particle size of a soil modifier may affect certain properties of the modified soil,necessitating future focused research.
基金supported by National Natural Science Foundation of China(Nos.52274343 and 52474370)the China Baowu Low Carbon Metallurgy Innovation Foundation(BWLCF202102).
文摘It is an important way to realize low carbon in China’s iron and steel industry by hydrogen-rich blast furnace smelting process.Sinter is the main blast furnace burden,and its reduction characteristics have a significant influence on ironmaking.The reduction behaviors,including reduction index(RI)and low-temperature reduction disintegration index(RDI),and the reduction mechanism of sinter in hydrogen-rich blast furnace were investigated.The results show that RI increased from 82.85 to 95.53 wt.%with an increase in H_(2)content from 0 to 30 vol.%,and the main phase of the reduction product was metallic iron.In the research of RDI,when the H_(2)content was increased from 0 to 20 vol.%,RDI+3.15 increased from 69.61 to 75.38 wt.%,and the main reaction was the reduction of hematite to magnetite.At 600-950℃,the reduction of sinter in CO and hydrogen-rich atmospheres(H_(2):CO=2)was both controlled by the first-order reaction model,and the apparent activation energy was 33.64 and 44.57 kJ/mol,respectively.
基金supported by the National Natural Science Foundation of China(Grant No.42162026)the Basic Research Program in Yunnan Province,China(Grant No.202401AT070328)the Young Talents Project of“Xingdian Talent Support Program"in Yunnan Province,China(Grant No.YNWR-QNBJ-2020-019).
文摘Disintegrated dolomite slope and tunnel disasters occur frequently due to poor water stability of disintegrated dolomite,primarily in a form of seepage failure.For engineering purposes,it is critical to determine the seepage properties of disintegrated dolomite within the strata.However,conventional experimental methods are time-consuming and expensive and may not be effective in investigating seepage characteristics due to the heterogeneity of disintegrated dolomite.In this study,pore network model(PNM)was established by the computerized tomography(CT)scanning technology to characterize the pores.Meanwhile,the seepage and coefficient of permeability under different inlet stress conditions based on the accurate pore model were realized by linking the commercial image processing software Avizo with the commercial multi-physics modeling package Comsol.The results show that the porosities of severely and completely disintegrated dolomites are 29.17% and 45.37%,respectively.The grade of pore development increases with disintegration grade,which facilitates seepage failure.Severely and completely disintegrated dolomites have the coefficients of permeability of 9.67×10^(-7) m/s and 1.61×10^(-6) m/s,respectively.Under conventional conditions,severely and completely disintegrated dolomites undergo seepage failure above a pressure difference of 6×10^(3) Pa and 5×10^(3) Pa,respectively.These results are consistent with both in situ water pressure tests in the borehole and laboratory tests with the constant-head method,demonstrating that CT scanning is an effective method for observing fractures and pores in disintegrated dolomite for seepage evaluation.
基金supported by the National Natural Science Foundation of China(7200120972231011+2 种基金72071206)the Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Province(2020RC4046)the Science Foundation for Outstanding Youth Scholars of Hunan Province(2022JJ20047).
文摘The rapid development of military technology has prompted different types of equipment to break the limits of operational domains and emerged through complex interactions to form a vast combat system of systems(CSoS),which can be abstracted as a heterogeneous combat network(HCN).It is of great military significance to study the disintegration strategy of combat networks to achieve the breakdown of the enemy’s CSoS.To this end,this paper proposes an integrated framework called HCN disintegration based on double deep Q-learning(HCN-DDQL).Firstly,the enemy’s CSoS is abstracted as an HCN,and an evaluation index based on the capability and attack costs of nodes is proposed.Meanwhile,a mathematical optimization model for HCN disintegration is established.Secondly,the learning environment and double deep Q-network model of HCN-DDQL are established to train the HCN’s disintegration strategy.Then,based on the learned HCN-DDQL model,an algorithm for calculating the HCN’s optimal disintegration strategy under different states is proposed.Finally,a case study is used to demonstrate the reliability and effectiveness of HCNDDQL,and the results demonstrate that HCN-DDQL can disintegrate HCNs more effectively than baseline methods.
文摘The oral disintegrating film(ODF)offers significant advantages such as superior patient compliance and rapid action onset as a form of solid drug delivery.However,the drug loading efficiency and dosage of the ODF currently available in the market are limited.To enhance the drug loading efficiency,with bacterial cellulose(BC)and hyaluronic acid(HA)as film-forming agents,glycerol(GL)as a plasticizer,and diprophylline(Dilor)as the model drug,a Dilor-ODF was prepared by a solvent casting method for the treatment of acute asthma-related diseases.The BC nano-network structure was utilized to augment the drug loading efficiency of the Dilor-ODF,while HA and GL were used to improve the elongation at break.The disintegration time,drug loading efficiency and drug releasing rate,and tensile properties of the Dilor-ODF were mainly evaluated.The results indicated that the Dilor-ODF exhibited a smooth surface with a uniform thickness and a maximum drug loading efficiency of(51.10±0.08)%.The time for complete disintegration and that for drug release in simulated oral saliva were less than 30 and 90 s,respectively,indicating the effect of rapid release.The tensile strength and elongation at break of the Dilor-ODF were(46.3±2.8)MPa and(1.9±0.2)%,respectively.The thermal decomposition temperature of the Dilor-ODF was higher than 200℃,satisfying subsequent processing demand.
基金Projects (50974035,51074047) supported by the National Natural Science Foundation of ChinaProject (20090407) supported by the Doctoral Fund of Ministry of Education,ChinaProject (200921007) supported by Liaoning Key Science and Technology,China
文摘In gas injection refining processes,wide dispersion of small bubbles in the bath is indispensable for high refining efficiency.Eccentric mechanical stirring with unidirectional impeller rotation was tested using a water model for pursuing better bubble disintegration and dispersion.Effects of various factors on bubble disintegration and dispersion were investigated.These factors were stirring mode,eccentricity and rotation speed,nozzle structure,nozzle immersion depth,and gas flow rate.Gas injection from a nozzle at the end of the impeller shaft and from an immersed lance was studied.Under eccentric stirring,a vortex was formed away from the shaft.Small bubbles were produced in the strong turbulence or high shear stress field near the rotating impeller and moved in the direction to the vortex keeping up with the macroscopic flow induced by the mechanical stirring.Thus small bubbles could disperse widely in the bath under eccentric stirring with unidirectional rotation.
文摘Ahn To develop a high resolution HPLC method for the determination of ondansetron in human plasma and to study the pharmacokinetics of ondansetron in orally disintegrating tablets. Methods HPLC determination involved liquid-liquid extraction, separation on a CN column and ultraviolet detection at 310 ran with granisetron as an internal standard. Pharmacokinetics and bioequivalence of ondansetron in orally disintegrating tablets by direct compression and conventional 8 mg tablets were evaluated and compared in 20 healthy human male volunteers after a single oral dose in a randomized cross-over study. Results The limit of quantification was 0.25 ng· mL^-1. The recovery was about 85 % or over for ondan setron and about 90% for internal standard. Linearity was good within the concentration range of 0.5 - 50 ng·mL^-1 with r^2 ranging from 0.997 1 to 0.999 9. Intra- and inter-assay coefficients of variation ranged from 1.78% to 2.38% and 3.88% -5.19%, respectively. Accuracies for spiked concentrations of 2.0, 10.0, and 30.0 ng·mL^-1 were 104.7% ±4.4%, 102.2% ± 1.1%, and99.51% ±2.34%, respectively. Pharmacokinetic parameters of AUCo-t, AUCo-∞ , Cmax, Tmax, and T1/2 were 230.2 ± 78.0 ng·h·L^-1 , 265.2± 101.5 ng·h·mL^-1, 35.67 ± 8.94 ng·mL^-l, 1.51 ±0.79 h, and 5.00± 1.41 h for orally disintegrating tablets, respectively. The analysis of variance did not show any significant difference between orally disintegrating tablets and conventional tablets, and 90% confidence intervals fell within the acceptable range for bioequivalence. Conclusion High resolution HPLC method has been set up and applied in pharmacokinetic evaluation of ondansetron in orally disintegrating tablets.
文摘Aim The aim of the present study was to prepare tablets which can rapidlydisintegrate in saliva, containing active ingredient in high dose (37.5% W/W). Methods Rapidlydisintegrating tablets containing rotundine were prepared by direct compression, wet granulation andmoulding, respectively . Different disintegrants and excipients were decided by single factor test.The typical disintegration time measurement and a new method of wetting time measuring wereintroduced for assessing rapidly disintegrating tablets. Results The tablets (80 mg) prepared bydirect compression have the crushing strength of 4.0 kg ?mm^(-2) and rapidly disintegratewithin 15 s in the saliva of healthy volunteers; the tablets prepared by wet granulation also havesufficient strength, a little longer but acceptable disintegration time (within 25 s in saliva) ;and the tablets obtained by moulding show disintegration within 40 s in saliva but low strength (2kg·mm^(-2)) . Disintegration time profiles of tablets are similar to those of wetting time, and thedisintegration and wetting times in vitro are similar to the disintegration time in vivo, thelatter having higher correlation with that in oral cavity. Conclusion The rapidly disintegratingtablets can be prepared by using these three techniques and excipients. Both in vitro disintegrationtime and wetting time are necessary indexes for judgment of in vitro disintegration profile.
文摘BACKGROUND Late infantile ceroid lipofuscinosis is a rare neurodegenerative disorder that appears between the ages of 2 and 4 years and is difficult to diagnose. In this report we present two sisters with this condition, and the clinical course consisted of delayed developmental skills initially and later regression of previously acquired skills. The cases were initially considered as childhood disintegrative disorder(CDD); however, when whole exome sequencing(WES) genetic testing was done, they proved to be variant late infantile ceroid lipofuscinosis. This is the first report from Jordan.CASE SUMMARY Clinical presentation included developmental delay and initially speech delay,followed by lose of sphincter control. Motor development was normal until 4 years of age, then they developed ataxia(fear of going downstairs) and weakness while walking. Atonic and myoclonic seizures become intractable, and this was followed by inability to stand or sit and loss of expressive language. In addition to complete blood count test, liver function test, kidney function test, serum electrolyte test, and blood sugar test, serum amino acid profile, B12 level test,thyroid function test, and a brain computed tomography scan were also normal.An electroencephalogram showed a generalized spike and wave pattern, and magnetic resonance imaging showed little to no abnormalities. After dealing with the cases as CDD, WES testing proved a final diagnosis of variant late infantile ceroid lipofuscinosis. Current treatment is anti-epileptic drugs and supportive care at home, and they are now in vegetative state.CONCLUSION This report highlights the importance of WES for the identification of genetic diseases, especially neurodegenerative disorders.
基金supported by the National Natural Science Foundation of China (Nos. 41877228, 41877229 and 42102303)Guangdong Basic and Applied Basic Research Foundation (Nos. 2018B030311066 and 2019A1515010554)+1 种基金China Postdoctoral Science Foundation (No. 2019M663241)Science and Technology Program of Guangzhou, China (No. 201904010136)。
文摘The disintegration of granite residual soil is especially affected by variations in physical and chemical properties. Serious geologic hazards or engineering problems are closely related to the disintegration of granite residual soil in certain areas. Research on the mechanical properties and controlling mechanisms of disintegration has become a hot issue in practical engineering. In this paper, the disintegration characteristics of improved granite residual soil are studied by using a wet and dry cycle disintegration instrument, and the improvement mechanism is analyzed. The results show that the disintegration amounts and disintegration ratios of soil samples treated with different curing agents are obviously different. The disintegration process of improved granite residual soil can be roughly divided into 5 stages:the forcible water intrusion stage, microcrack and fissure development stage, curing and strengthening stage, stable stage, and sudden disintegration stage. The disintegration of granite residual soil is caused by the weakening of the cementation between soil particles under the action of water. When the disintegration force is greater than the anti-disintegration force of soil, the soil will disintegrate. Cement and lime mainly rely on ion exchange agglomeration, the inclusion effect of curing agents on soil particles, the hard coagulation reaction and carbonation to strengthen granite residual soil. Kaolinite mainly depends on the reversibility of its own cementation to improve and strengthen granite residual soil. The reversibility of kaolinite cementation is verified by investigating pure kaolinite with a tensile, soaking, drying and tensile test cycle. Research on the disintegration characteristics and disintegration mechanism of improved granite residual soil is of certain reference value for soil modification.
基金supported by the National Natural Science Foundation of China(Nos.50490275 and 50778184)
文摘Size and quantity of fractured zone and non-fractured zone are controlled by cracks contained in deep rock masses. Zonal disintegration mechanism is strongly dependent on the interaction among cracks. The strong interaction among cracks is investigated using stress superposition principle and the Chebyshev polynomials expansion of the pseudo-traction. It is found from numerical results that crack nucleation, growth and coalescence lead to failure of deep crack- weakened rock masses. The stress redistribution around the surrounding rock mass induced by unloading excavation is studied. The effect of the excavation time on nucleation, growth, interaction and coalescence of cracks was analyzed. Moreover, the influence of the excavation time on the size and quantity of fractured zone and non-fractured zone was given. When the excavation time is short, zonal disintegration phenomenon may occur in deep rock masses. It is shown from numerical results that the size and quantity of fractured zone increase with decreasing excavation time, and the size and quantity of fractured zone increase with the increasing value of in-situ geostress.
基金supported by the State Key Program of National Natural Science Foundation of China(72231011)the National Natural Science Foundation of China(72071206,72001209,71971213)the Science Foundation for Outstanding Youth Scholars of Hunan Province(2022JJ20047).
文摘Complex systems widely exist in nature and human society.There are complex interactions between system elements in a complex system,and systems show complex features at the macro level,such as emergence,self-organization,uncertainty,and dynamics.These complex features make it difficult to understand the internal operation mechanism of complex systems.Networked modeling of complex systems is a favorable means of understanding complex systems.It not only represents complex interactions but also reflects essential attributes of complex systems.This paper summarizes the research progress of complex systems modeling and analysis from the perspective of network science,including networked modeling,vital node analysis,network invulnerability analysis,network disintegration analysis,resilience analysis,complex network link prediction,and the attacker-defender game in complex networks.In addition,this paper presents some points of view on the trend and focus of future research on network analysis of complex systems.
文摘Hydrogen-enrich iron making process is certainly to be an effective method to reduce greenhouse gases emission.However,the effect of hydrogen addition on the low temperature metallurgical property of sinter is still unclear.A detailed investigation was performed on the above topic.The results are as follows.When CO is partially replaced by H2,the RDI〈3.15（RDI〈2.8） of sinter decreases with the increase of the H2 content;when the content of H2 increases,the CO,CO2 and N2 decrease proportionally,in this case,RDI〈3.15（RDI〈2.8） of sinter increases with the increase of H2 content;the value of RDI〈3.15（RDI〈2.8） basically depends on the reduction index（Ri）.The experimental data of RDI〈2.8 based on Japanese industrial standard（JIS） are a little higher than the data of RDI〈3.15 based on Chinese industrial standard（CIS） in the same condition.In addition,for part of CO is replaced by H2：RDI〈2.8=3.38394＋1.1585 RDI〈3.15;for other gases,except H2,are decreased proportionally：RDI〈2.8=17.39678＋0.42922 RDI〈3.15
基金Supported by the National Natural Science Foundation of China (51078371,51021001)the Natural Science Foundation Project of CQ CSTC (2009BA4046,2009AB6194)
文摘Rock masses without pre-existing macrocracks can usually be considered as granular materials with only microcracks.During the excavation of the tunnels,microcracks may nucleate,grow and propagate through the rock matrix;secondary microcracks may appear,and discontinuous and incompatible deformation of rock masses may occur.The classical continuum elastoplastic theory is not suitable for analyzing discontinuous and incompatible deformation of rock masses.Based on non-Euclidean model of the discontinuous and incompatible deformation of rock masses,the distribution of stresses in the surrounding rock masses in deep tunnels is fluctuant or wave-like.The stress concentration at the tips of microcracks located in vicinity of stress wave crest is comparatively large,which may lead to the unstable growth and coalescence of secondary microcracks,and consequently the occurrence of fractured zones.On the other hand,the stress concentration at the tips of microcracks located around stress wave trough is relatively small,which may lead to the arrest of microcracks,and thus the non-fractured zones.The alternate appearance of stress wave crest and trough thus may induce the alternate occurrence of fractured and non-fractured zones in deep rock masses.For brittle rocks,the dissipated energy of microcrack growth is small,but the elastic strain energy stored in rock masses may be larger than the dissipated energy growths of pre-existing microcracks and secondary microcracks.The sudden release of the residual elastic strain energy may lead to rockburst.Based on this understanding,the criteria of rockburst are established.Furthermore,the relationship between rockbursts and zonal disintegration in the surrounding rock masses around deep tunnels is studied.The influences of the in-situ stresses and the physico-mechanical parameters on the distribution of rockburst zones and the ejection velocity of rock fragments are investigated in detail.
