Double-layer Method Research Articles

Transient carriage and low-level colonization of orally administrated lytic and temperate phages in the gut of mice

Many studies have shown the efficacy of phage therapy in reducing gastrointestinal pathogens. However, it is unclear whether phages can successfully colonize the gut when administered in an adequate amount for a long time. About 1 × 108 PFU/mL of purified lytic phage PA13076 or temperate phage BP96115 were fed daily to mice via drinking water over 31 days, to elucidate the distribution of phages in the gastrointestinal tract. At day 16 and 31, six different segments of the gastrointestinal tract with their contents, including stomach, duodenum, jejunum, ileum, cecum, colon, and fresh feces, were aseptically collected. The phage titers were determined using the double-layered plate method with S. Enteritidis ATCC 13076 or S. Pullorum SPu-109 used as host cells. The results indicated that a small portion of administered phages survived exposure to gastric acid and entered the intestinal tract. The prevalence of phages in the gastrointestinal tract was lower than 1% of the primary phage count. Highest phage titers were detected in the cecum with 104 ~ 105 PFU/g, and most of the phages were eliminated from the body via feces with 106 PFU/g. On day 16 and day 31, the same level of phage titers in different segments of the gastrointestinal tract indicated that the colonization of phages had reached saturation at day 16. These results demonstrate transient phage carriage and low-level colonization of orally administrated lytic and temperate gut phages in mice.Graphical abstract

Antibacterial Activity of Bacteriocinogenic Commensal Escherichia coli against Zoonotic Strains Resistant and Sensitive to Antibiotics.

Antibiotic resistance concerns various areas with high consumption of antibiotics, including husbandry. Resistant strains are transmitted to humans from livestock and agricultural products via the food chain and may pose a health risk. The commensal microbiota protects against the invasion of environmental strains by secretion of bacteriocins, among other mechanisms. The present study aims to characterize the bactericidal potential of bacteriocinogenic Escherichia coli from healthy humans against multidrug-resistant and antibiotic-sensitive strains from pigs and cattle. Bacteriocin production was tested by the double-layer plate method, and bacteriocin genes were identified by the PCR method. At least one bacteriocinogenic E. coli was detected in the fecal samples of 55% of tested individuals, adults and children. Among all isolates (n = 210), 37.1% were bacteriocinogenic and contained genes of colicin (Col) Ib, ColE1, microcin (Mcc) H47, ColIa, ColM, MccV, ColK, ColB, and single ColE2 and ColE7. Twenty-five E. coli carrying various sets of bacteriocin genes were further characterized and tested for their activity against zoonotic strains (n = 60). Strains with ColE7 (88%), ColE1-ColIa-ColK-MccH47 (85%), MccH47-MccV (85%), ColE1-ColIa-ColM (82%), ColE1 (75%), ColM (67%), and ColK (65%) were most active against zoonotic strains. Statistically significant differences in activity toward antibiotic-resistant strains were shown by commensal E. coli carrying MccV, ColK-MccV, and ColIb-ColK. The study demonstrates that bacteriocinogenic commensal E. coli exerts antagonistic activity against zoonotic strains and may constitute a defense line against multidrug-resistant strains.

A double-layer heating method to generate high temperature in a two-stage multi-anvil apparatus**Project supported by the National Natural Science Foundation of China (Grant No. 51872189) and the Fundamental Research Funds for the Central Universities, China (Grant No. 2018SCUH0022).

A new heating method is proposed to increase the cell temperature of the 6–8 type multi-anvil apparatus without reducing the volume of the sample chamber. The double-layer heater assembly (DHA) has two layers of heaters connected in parallel. The temperature of the cell was able to reach 2500 °C by using 0.025 mm rhenium foils, and the temperature limit was increased by 25% compared with that of the traditional single-layer assembly. The power–temperature relationships for these two assemblies with different sizes were calibrated by using W/Re thermocouple at 20 GPa. When the volume of samples was the same, the DHA not only attained higher temperature, but also kept the holding time longer, compared to the traditional assembly. The results of more than ten experiments showed that the new 10/4 DHA with a relatively large sample size (2 mm in diameter and 4 mm in height) can work stably with the center temperature of the sample cavity exceeding 2300 °C under the pressure of 20 GPa.

Thrust Performance Improvement for PMSLM Through Double-Layer Reverse Skewed Coil and WRF-MKH Method

This article is dedicated to achieving the best thrust performance of high thrust and low thrust ripple of permanent magnet synchronous linear motors (PMSLMs), which are used in precision positioning system. To achieve this, a novel PMSLM with double-layer reverse skewed coil (DRSC) is designed and optimized. First, the topological structure of the DRSC-PMSLM is introduced, and the effectiveness of the DRSC is analyzed qualitatively according to the analytic model. Certain hypotheses that are more suited to qualitative analysis can lead to the low accuracy of the analytic model. Therefore, for the subsequent optimization, the weighted random forest (WRF), an enhanced random forest (RF) algorithm by assigning different weights to different regression trees, is proposed to fit the sample data generated by the finite element method to establish a high-precision proxy model. Accuracy test proves that the WRF model has higher accuracy than the standard RF model and the analytical model. Subsequently, a new global optimization algorithm, call the modified Krill Herd (MKH) algorithm is proposed to iteratively optimize the WRF model to obtain the optimal structure parameters. The MKH algorithm is a modified KH algorithm that two strategies are used to improve the convergence rate and avoid premature convergence. Comparative experiments are performed by using genetic algorithm, particle swarm optimization, and standard Krill herd, which prove that the MKH has faster convergence speed and stronger global search capability. The thrust performance of the optimized motor is improved considerably compared with that of the initial motor, which further proves the effectiveness of the MKH used in this article. Finally, the prototype experiment proves that the PMSLM with DRSC has the best thrust performance.

Isolation and selection of Bacillus strains with high potential probiotic that used in catfish farming (Pangasianodon hypophthalmus)

In this study, we isolated 28 strains of Bacillus spp. from water samples, catfish pond mud samples and earthworm manure (Perionyx excavates). By the cross-streak agar methods, 22 Bacillus strains showed the inhibition ability to Edwardsiella ictaluri, which caused Bacillary Necrosis Pangasius (BNP) in catfish (Pangasianodon hypophthalmus). Both Bacillus sp. Q16 and Q111 strains showed the highest inhibition to E. ictaluri by the double-layer agar methods. Finally, two Bacillus strains (Q16, Q111) were selected as a source of potential probiotic because of the ability of extracellular enzyme secretion (protease, amylase, cellulose) strong growth at 0,1-1% salt concentrations, survival within the pH range 6-8, resistance to low pH and low bile salts, inability to produce haemolysin enzyme, sensitivity to eight antibiotics in the three impacting groups (inhibition of wall synthesis, inhibition mechanism of protein synthesis, inhibition of nucleic acid synthesis). Two Bacillus strains (Q16, Q111) were identified that they belong to Bacillus subtilis by biochemical method and 16S rRNA gene sequencing method. This study indicated that two Bacillus strains (Q16, Q111) isolated from catfish pond can be applied as high potential probiotics that used to farm catfish.

Influence of Feeding Techniques in Bottom Tapping Stir Casting Process for Fabrication of Alumina Nano-filler-reinforced Aluminium Composites

Stir casting process is a prominent technique for the fabrication of aluminium matrix composites (AlMMCs). Regular feeding, two-step feeding, capsulate feeding, pre-melt feeding and double-layer feeding are different feeding methods used in stir casting technique. In this study, Al7075-MMCs reinforced with nano-sized Al2O3 are manufactured through five different feeding methods. The bonding between the matrix and ceramic interface, agglomeration of the particles and porosity are evaluated through scanning electron microscope. From the micro-structural characterization results, it is observed that double-layer feeding method ensures the better particle distribution and improved bonding between the Al7075 and Al2O3. Alumina particles of 50 nm size, 2.5 wt% are incorporated to the Al7075 matrix. The intensive porosity and high agglomeration are noticed in other methods. It is understood from the results that double-layer feeding technique is a promising route for producing the defect-free Al7075-MMCs. The density, micro-hardness, and tensile strength of the resultant composites are measured according to ASTM standards. Due to homogenous particle distribution, the ultimate tensile strength is increased from 280 to 387 MPa, which is 38% higher than Al7075. The yield strength of the composite is increased from 140 to 198 MPa. The micro-hardness is increased from 661 to 878 MPa.

Optimization Model of Key Equipment Maintenance Scheduling for an AC/DC Hybrid Transmission Network Based on Mixed Integer Linear Programming

The unbalanced distribution of resource and consuming centers in China has prompted the AC/DC hybrid transmission technology. The maintenance scheduling of an AC/DC hybrid transmission network is the key technology to ensure its safety and reliability. In this study, the mutual influence mechanism of an AC/DC system in a maintenance period was analyzed in detail. The overhead transmission line and transformer are key equipment within an AC/DC hybrid transmission network, and an optimization model of the key equipment maintenance scheduling was established. The objective of the model was to improve the system reliability during the maintenance scheduling. By considering the constraints of maintenance cost, maintenance resources, and maintenance workload, the maintenance scheduling of overhead transmission lines and transformer branches was obtained. The over-limit situation of power flow and the weakness of the system during the maintenance period was evaluated. The “double-layer substitution method” was adopted to convert the nonlinear constraints into its bilinear formulation such that it could then be solved. The random number sampling method was used to quantify the system reliability, and the commercial optimization software was used to solve the optimized scheduling. Based on the improved IEEE RTS-79 system and the Hubei Province electrical system, the simulation results showed the effectiveness of the proposed method.

Effect of N2O produced by indigenous denitrifiers in oil reservoir on the physical properties of crude oil

The success of microbial enhanced oil recovery (MEOR) relies on complex microbial processes. Nevertheless, the contribution and mechanism of in-situ denitrification to microbial oil recovery remain unclear. In this study, eight denitrifying bacterial strains, designated T1, D1, D44, D46, D15, S1, S2 and S6, were isolated from the produced water of Xinjiang Oilfield, China, by a double layered plate method. The16S rDNA gene sequences of these denitrifying strains shared 100% similarity with Pseudomonas stutzeri (T1, D1, and D44), Pseudomonas putida (D46 and D15), and Pseudomonas aeruginosa (S1, S2, S6), respectively. The N2O production effects of these strains on the physical properties of crude oil were evaluated with batch experiment. Results showed that the highest total gas yield was observed with sucrose as carbon source, and the maximal concentration of N2O occurred with glycerol as carbon source. The denitrification process by these bacterial strains led to volume expansion and viscosity reduction of crude oil. Crude oil expansion rate was positively correlated with the concentration of N2O, with a correlation coefficient of 0.983, but not correlated with the volume of total gas production. Strain S1, S2, and S6 produced 530-730 mg·L-1 of surfactant using glycerol as ole carbon source, which could reduce surface tension and emulsify crude oil. However, these surfactant-producing strains produced less N2O, exhibited weaker effects on oil swelling and viscosity reduction, compared to the none-surfactant-producing denitrifying strains. Our results suggested that more attention should be paid to the ability of N2O production by denitrifying bacteria when exploiting microbial resources towards enhancing oil recovery.

A double layer potential approach for planar Cauchy problems for the Laplace equation

We derive a double-layer potential approach which recasts the ill-posed Cauchy problem for the Laplace equation in a planar bounded doubly-connected domain as a system of boundary integral equations. It is shown that the system has a unique solution for a dense set of data. For the integral equations involved having a hypersingular kernel the Nystr\"om method based on trigonometrical quadratures is applied. The resulting fully discrete linear system is solved by Tikhonov regularization. Results included of numerical experiments show that a stable approximation can be obtained with the double-layer method to the solution of the Cauchy problem.

CHARACTERISTICS AND EFFECTIVENESS OF CHITOSAN ORININATED FROM THE CARAPACE OF T. ANOMALA SHRIMP AS AN ANTIBACTERIAL COMPOUND

This study aims to investigate the inhibition zones of the chitosan against Pseudomonas aeruginosa. Carapace from T. anomala is used as raw material of chitosan. There were 5 treatments used, namely positive control (K0+), negative control (K0-), 5% chitosan (K1), 7% chitosan (K2) and 9% (K3) chitosan. The carapace was taken and then washed, dried, refined, demineralization, de-preoteinated, deasitelation and was tested using double layer method, discs and well diffusion. The proximate carapace test results were as follows, water content was 68.18 % gross wight (gw), moisture content 11.77 % dry wight (dw) protein content, 2.35 %dw fat content, 84.43 %dw ash content and carbohydrate content was 1.45 %dw. The chitosan of T. anomala characteristics were yellowish white flakes, odorless and tasteless with yield value, moisture content, ash content, mineral content (Ca, Fe, K, Na, P) and the degree of deacetylation 27.51 %; 7.31 %gw; 3.40 %dw; 12.17 mg/L; 4.90 mg/L; 3.40 mg/L; 5.49 mg/L; 0.27 mg/L; and 73.43 % respectively , Results on antimicrobial sensivity tests using double layer, disk blank and well diffusion. Shown clear zone, 13.87 mm, 11.34 mm and 14.62 mm. these values indicate that the antimicrobial effect of the chitosan is strong.

Biological control of Pseudomonas syringae pv. garcae in coffee crop with Bacillus spp. isolates

Among the diseases that affect the coffee crop, bacterial blight caused by Pseudomonas syringae pv. garcae (Psg) stands out due to production losses. This study evaluates the antagonistic effect of Bacillus spp. against Psg both in vitro and in coffee seedlings. In vitro antagonism was evaluated by the double layer method for the inhibition of Psg growth. Subsequently, in vitro selected antagonists were tested for their ability to inhibit bacteriosis in coffee seedlings (cv. Mundo Novo) under greenhouse conditions. It was evaluated nonspecific met­abolic production by antagonistic bacteria and identified the isolates that stood out in the in vitro experiment. Iso­lates considered as the most promising in vitro experiments (23% of the total) were chosen for the antagonistic efficiency test in a greenhouse. Isolates B04, B05, B22, B31, B53, B202, B208, B264, B266, and B294 showed ammonia production. Isolates B04, B33, and B294 showed hydrocyanic acid production. Isolates B04, B05, B18, B22, B33, B53, B105, B202, B208, B264, and B294 showed siderophores production. In addition, isolates B18 ( B. subtilis ), B22 ( B. thuringiensis serovar israelensis ), B05 ( B. methylotrophicus ), B53 ( B. safensis ), B202 ( B. subtilis ), and B33 ( B. subtilis ) reduced more than 80% the severity of bacterial blight under greenhouse condi­tions. Field experiments should be conducted to confirm the potential of these isolates for bacterial blight man­agement.

A newly isolated roseophage represents a distinct member of Siphoviridae family

BackgroundMembers of the Roseobacter lineage are a major group of marine heterotrophic bacteria because of their wide distribution, versatile lifestyles and important biogeochemical roles. Bacteriophages, the most abundant biological entities in the ocean, play important roles in shaping their hosts’ population structures and mediating genetic exchange between hosts. However, our knowledge of roseophages (bacteriophages that infect Roseobacter) is far behind that of their host counterparts, partly reflecting the need to isolate and analyze the phages associated with this ecologically important bacterial clade.MethodsvB_DshS-R4C (R4C), a novel virulent roseophage that infects Dinoroseobacter shibae DFL12T, was isolated with the double-layer agar method. The phage morphology was visualized with transmission electron microscopy. We characterized R4C in-depth with a genomic analysis and investigated the distribution of the R4C genome in different environments with a metagenomic recruitment analysis.ResultsThe double-stranded DNA genome of R4C consists of 36,291 bp with a high GC content of 66.75%. It has 49 genes with low DNA and protein homologies to those of other known phages. Morphological and phylogenetic analyses suggested that R4C is a novel member of the family Siphoviridae and is most closely related to phages in the genus Cronusvirus. However, unlike the Cronusvirus phages, R4C encodes an integrase, implying its ability to establish a lysogenic life cycle. A terminal analysis shows that, like that of λ phage, the R4C genome utilize the ‘cohesive ends’ DNA-packaging mechanism. Significantly, homologues of the R4C genes are more prevalent in coastal areas than in the open ocean.ConclusionsInformation about this newly discovered phage extends our understanding of bacteriophage diversity, evolution, and their roles in different environments.

Characterization of the narrow-spectrum bacteriophage LSE7621 towards Salmonella Enteritidis and its biocontrol potential on lettuce and tofu

As the natural antibacterial agents, bacteriophages have great potential for controlling food pathogens. Compared to broad-spectrum bacteriophages, narrow-spectrum bacteriophages can reduce the risk of developing community-wide resistance and have little impact on microbial flora. The present study aimed to isolate and characterize a narrow-spectrum bacteriophage that effectively controlled Salmonella enterica serovar Enteritidis (Salmonella Enteritidis) in food. A narrow-spectrum bacteriophage LSE7621, which can effectively lyse Salmonella Enteritidis, was obtained from sewage by the double-layer agar plate method. LSE7621, which belonged to the order Caudovirales and family Myoviridae, showed good pH tolerance (pH 4.0–11.0) and thermal stability (30–50 °C). LSE7621 was able to significantly and effectively control Salmonella on lettuce and tofu (p < 0.05). When LSE7621 was administered on lettuce, the number of Salmonella was reduced by 0.86 log10 CFU/mL (MOI = 100) and 1.02 log10 CFU/mL (MOI = 1) within 6 h. When LSE7621 was administered on tofu, the number of Salmonella decreased by 3.55 log10 CFU/mL (MOI = 100) and 1.86 log10 CFU/mL (MOI = 1) within 4 h. This is the first report about narrow-spectrum bacteriophage infecting Salmonella Enteritidis. This study provides insights into fundamental researches on narrow-spectrum bacteriophage and facilitates the utilization of new bacteriophage resource.

Bacteriophage Isolation and Characterization: Phages of Escherichia coli.

Here we introduce methods for the detection, enumeration, and isolation of bacteriophages from Escherichia coli. In bacteria, horizontal gene transfer may be mediated by virulent and temperate phages. Strict virulent phages, able to propagate in a suitable strain following the lytic pathway, can be isolated directly from different natural environments. In temperate phages, the lytic cycle must be activated, and phages are detected after their induction. In both cases, detection is based on the production of visible plaques in a confluent lawn of the host strain using a double agar layer method. Further purification and characterization are achieved by density gradients, electron microscopy studies, and genomic analysis. This straightforward methodology can be applied to the detection, enumeration, and isolation of bacteriophages from any bacterial species, using the appropriate host strain, media, and culture conditions.

On single-step HSS iterative method with circulant preconditioner for fractional diffusion equations

By exploiting Toeplitz-like structure and non-Hermitian dense property of the discrete coefficient matrix, a new double-layer iterative method called SHSS-PCG method is employed to solve the linear systems originating from the implicit finite difference discretization of fractional diffusion equations (FDEs). The method is a combination of the single-step Hermitian and skew-Hermitian splitting (SHSS) method with the preconditioned conjugate gradient (PCG) method. Further, the new circulant preconditioners are proposed to improve the efficiency of SHSS-PCG method, and the computation cost is further reduced via using the fast Fourier transform (FFT). Theoretical analysis shows that the SHSS-PCG iterative method with circulant preconditioners is convergent. Numerical experiments are given to show that our SHSS-PCG method with circulant preconditioners preforms very well, and the proposed circulant preconditioners are very efficient in accelerating the convergence rate.

DNA Biosensor Based on Double-Layer Discharge for the Detection of HPV Type 16.

DNA electrochemical biosensors represent a feasible alternative for the diagnosis of different pathologies. In this work, the development of an electrochemical method for Human Papillomavirus-16 (HPV-16) sensing is reported based on potential relaxation measurements related to the discharge of a complex double layer of a DNA-modified gold electrode. The method used allows us to propose an equivalent circuit (EC) for a DNA/Au electrode, which was corroborated by electrochemical impedance spectroscopy (EIS) measurement. This model differs from the Randles circuit that is commonly used in double-layer simulations. The change in the potential relaxation and associated charge transfer resistance were used for sensing the DNA hybridization by using the redox pair Fe(CN)64-/Fe(CN)63+ as an electrochemical indicator. In order to determinate only the potential relaxation of the composed double layer, the faradic and double-layer current contributions were separated using a rectifier diode arrangement. A detection limit of 0.38 nM was obtained for the target HPV-16 DNA sequences. The biosensor showed a qualitative discrimination between a single-base mismatched sequence and the fully complementary HPV-16 DNA target. The results indicate that the discharge of the double-layer detection method can be used to develop an HPV DNA biosensor.

Directed evolution of a 6-phosphogluconate dehydrogenase for operating an enzymatic fuel cell at lowered anodic pHs

Most enzymatic fuel cells (EFCs) are designed for operating at physiological conditions and cannot stand for low pHs due to the enzyme denaturation. Improving the acid tolerance of EFCs represents the increased robustness and diversity of their practical applications. In this study, we successfully constructed a three-enzyme pathway-catalyzed EFC consisting of two dehydrogenases and a diaphorase that can be operated at the anodic pH of 5.4. The acid-intolerance of one enzyme, 6-phosphogluconate dehydrogenase, was overcome by enzyme engineering. After the directed evolution including three rounds of error-prone PCR and a petri-dish-based double-layer screening method, the best 6-phosphogluconate dehydrogenase mutant (named as 3-3) exhibited a 42-fold increase in catalytic efficiency at pH 5.4 compared to the original enzyme. The electrochemical measurements revealed that the EFC equipped with this mutant achieved a maximum power density of 0.13 mW cm−2 at pH 5.4, more than 10-fold higher than that with the same enzyme unit loading but at pH 7.3. Under a high loading amount of enzymes, the EFC yielded a maximum power density of ∼0.5 mW cm−2, and that with the mutant also exhibited an improved stability. This study demonstrates that lowering anodic pH may be a useful strategy for constructing high-performance and robust EFCs and the concerns for enzyme deactivation can be addressed by enzyme engineering.

The Effects of Layer Thickness of Radar Absorbing Materials Prepared by Double Layer Method on X-Band Wavelength Frequency

Double layer coating with variations in layer thickness on radar absorbent material (RAM), and Polyaniline dobed by DBSA as a dielectric material has been successfully synthesized. As well as Barium M-Hexaferrite doped by Zn2+ at x=0.9 as magnetic material successfully synthesized. Polyaniline has been synthesized by polymerization method and Barium M-Hexaferrite has been synthesized by solid state method. Characterization results obtained the conductivity of Polyaniline and Barium M-Hexaferrite respectively 4.4 × 10-1 S/m and 2.09 × 10-3 S/m, both of which are in range of semiconductor materials conductivity. The presence of Zn2+ doping successfully reduced hard magnetic properties of Barium M-Hexaferrite to be soft magnetic, with coercivity field (Hc) equals 0.0181 Tesla. Based on research that has been done, represent that double layer design with variations PANi : PANi + BaM (3:1) has maximum reflection loss value about -29,6003 dB, and 96.69% of energy absorbed. Whereas in variation of PANi: PANi + BaM (3: 1) has minimum reflection loss value about -15.2937 dB, and 82.21% of energy absorbed. In addition, the coating thickness variations also affect the absorption band width, with the most effective absorption peaks in “D” variation with bandwidth equals 1.81 GHz in range of frequency 8 to 9.81 GHz.

Biological characteristics of bacteriophages infecting three typic rhizobia of legume

Bacteriophages infecting rhizobia of legume leads to a significant decrease in the number of rhizobia in soil and nodulation in legume, which finally affects nitrogen fixation and remarkably reduces crop yield. However, limited studies have focused on bacteriophages of rhizobia. In this study, three typic rhizobium strains of Bradyrhizobium diazoefficiens USDA110T, Sinorhizobium sojae CCBAU05684T and Sinorhizobium meliloti USDA1002T were used as the host bacteria. From each host, three rhizobiophages were isolated from an agricultural black soil with double-layer plate method. We isolated nine rhizobiophages and investigated their morphological feature and biological characteristics. The results showed that the phages of SMM (infecting Sinorhizobium meliloti USDA1002T) and BDM (infecting Bradyrhizobium diazoefficiens USDA110T) belonged to Myoviridae family, while phages of SSS (infecting Sinorhizobium sojae CCBAU05684T) belonged to Siphoviridae family. The optimal multiplicity of infection for nine phages ranged from 0.001 to 1.0. The one-step growth curve showed that the latent and rising periods of BDM were remarkably longer than that of SMM and SSS, but the bust size was minimal. Nine phages had the strongest infecting activity at 30-40 ℃ and at neutral pH condition. Comparative analysis showed that the biological characteristics of phages infected with the same host were different, with the differentiation being smaller than that of phages infected with different hosts.

Influence of high overload on the collimating lenses of laser ranging systems

Collimating lenses are an important component of laser ranging systems, and high overload environments severely affect the beam shaping effect of such lenses. This study proposes a buffer isolation method on the basis of impact stress wave attenuation theory for collimating lens spacers. ANSYS finite element software was applied to simulate the high load dynamics of collimating lenses, and the buffer isolation performance of different materials and composite structures was compared and analysed. Optical simulation analysis of the collimating lenses under different buffer conditions was performed using ZEMAX software to study the mechanism by which a high overload affects the collimating lenses. High overload and optical shaping experiments based on theoretical analysis were further conducted. Results showed the superiority of butadiene rubber to polytetrafluoroethylene after application of 70000 g impact acceleration. The combination-gasket method was superior to the single-gasket method, and the sandwich combination-gasket method was superior to the double-layer combination-gasket method.