Insights on advanced substrates for controllable fabrication of photoanodes toward efficient and stable photoelectrochemical water splitting

Conversion of solar energy into H2 by photoelectrochemical(PEC)water splitting is recognized as an ideal way to address the growing energy crisis and environmental issues.In a typical PEC cell,the construction of photoanodes is crucial to guarantee the high efficiency and stability of PEC reactions,which fundamentally rely on rationally designed semiconductors(as the active materials)and substrates(as the current collectors).In this review work,we start with a brief introduction of the roles of substrates in the PEC process.Then,we provide a systematic overview of representative strategies for the controlled fabrication of photoanodes on rationally designed substrates,including conductive glass,metal,sapphire,silicon,silicon carbide,and flexible substrates.Finally,some prospects concerning the challenges and research directions in this area are proposed.

Kinematic deformation and intensity assessment of the 2021 Maduo M_(S)7.4 earthquake in Qinghai revealed by high-frequency GNSS

Rapid acquisition of the kinematic deformation field and seismic intensity distribution of large earthquakes is crucial for postseismic emergency rescue,disaster assessment,and future seismic risk research.The advancement of GNSS observation and data processing makes it play an important role in this field,especially the high-frequency GNSS.We used the differential positioning method to calculate the 1 HZ GNSS data from 98 sites within 1000 km of the M_(S)7.4 Maduo earthquake epicenter.The kinematic deformation field and the distribution of the seismic intensity by using the peak ground velocity derived from displacement waveforms were obtained.The results show that:1)Horizontal coseismic response deformation levels ranging from 25 mm to 301 mm can be observed within a 1000 km radius from the epicenter.Coseismic response deformation on the east and west sides shows bilateral asymmetry,which markedly differs from the symmetry presented by surface rupture.2)The seismic intensity obtained through high-frequency GNSS and field investigations exhibits good consistency of the scope and orientation in the high seismic intensity area,although the former is generally slightly smaller than the latter.3)There may exist obstacles on the eastern side of the seismogenic fault.The Maduo earthquake induced a certain tectonic stress loading effect on the western Kunlun Pass-Jiangcuo fault(KPJF)and Maqin-Maqu segment,resulting in higher seismic risk in the future.

Dynamic Response of Foundations during Startup of High-Frequency Tunnel Equipment

The specialized equipment utilized in long-line tunnel engineering is evolving towards large-scale,multifunctional,and complex orientations.The vibration caused by the high-frequency units during regular operation is supported by the foundation of the units,and the magnitude of vibration and the operating frequency fluctuate in different engineering contexts,leading to variations in the dynamic response of the foundation.The high-frequency units yield significantly diverse outcomes under different startup conditions and times,resulting in failure to meet operational requirements,influencing the normal function of the tunnel,and causing harm to the foundation structure,personnel,and property in severe cases.This article formulates a finite element numerical computation model for solid elements using three-dimensional elastic body theory and integrates field measurements to substantiate and ascertain the crucial parameter configurations of the finite element model.By proposing a comprehensive startup timing function for high-frequency dynamic machines under different startup conditions,simulating the frequency andmagnitude variations during the startup process,and suggesting functions for changes in frequency and magnitude,a simulated startup schedule function for high-frequency machines is created through coupling.Taking into account the selection of the transient dynamic analysis step length,the dynamic response results for the lower dynamic foundation during its fundamental frequency crossing process are obtained.The validation checks if the structural magnitude surpasses the safety threshold during the critical phase of unit startup traversing the structural resonance region.The design recommendations for high-frequency units’dynamic foundations are provided,taking into account the startup process of the machine and ensuring the safe operation of the tunnel.

Influence of substrate effect on near-field radiative modulator based on biaxial hyperbolic materials

Relative rotation between the emitter and receiver could effectively modulate the near-field radiative heat transfer(NFRHT)in anisotropic media.Due to the strong in-plane anisotropy,natural hyperbolic materials can be used to construct near-field radiative modulators with excellent modulation effects.However,in practical applications,natural hyperbolic materials need to be deposited on the substrate,and the influence of substrate on modulation effect has not been studied yet.In this work,we investigate the influence of substrate effect on near-field radiative modulator based onα-MoO_(3).The results show that compared to the situation without a substrate,the presence of both lossless and lossy substrate will reduce the modulation contrast(MC)for different film thicknesses.When the real or imaginary component of the substrate permittivity increases,the mismatch of hyperbolic phonon polaritons(HPPs)weakens,resulting in a reduction in MC.By reducing the real and imaginary components of substrate permittivity,the MC can be significantly improved,reaching 4.64 forε_(s)=3 at t=10 nm.This work indicates that choosing a substrate with a smaller permittivity helps to achieve a better modulation effect,and provides guidance for the application of natural hyperbolic materials in the near-field radiative modulator.

Enhanced resonance frequency in Co2FeAl thin film with different thicknesses grown on flexible graphene substrate

The flexible materials exhibit more favorable properties than most rigid substrates in flexibility,weight saving,mechanical reliability,and excellent environmental toughness.Particularly,flexible graphene film with unique mechanical properties was extensively explored in high frequency devices.Herein,we report the characteristics of structure and magnetic properties at high frequency of Co2FeAl thin film with different thicknesses grown on flexible graphene substrate at room temperature.The exciting finding for the columnar structure of Co2FeAl thin film lays the foundation for excellent high frequency property of Co2FeAl/flexible graphene structure.In-plane magnetic anisotropy field varying with increasing thickness of Co2FeAl thin film can be obtained by measurement of ferromagnetic resonance,which can be ascribed to the enhancement of crystallinity and the increase of grain size.Meanwhile,the resonance frequency which can be achieved by the measurement of vector network analyzer with the microstrip method increases with increasing thickness of Co2FeAl thin film.Moreover,in our case with graphene film,the resonance magnetic field is quite stable though folded for twenty cycles,which demonstrates that good flexibility of graphene film and the stability of high frequency magnetic property of Co2FeAl thin film grown on flexible graphene substrate.These results are promising for the design of microwave devices and wireless communication equipment.

Recess-free enhancement-mode AlGaN/GaN RF HEMTs on Si substrate

Enhancement-mode(E-mode)GaN-on-Si radio-frequency(RF)high-electron-mobility transistors(HEMTs)were fabri-cated on an ultrathin-barrier(UTB)AlGaN(<6 nm)/GaN heterostructure featuring a naturally depleted 2-D electron gas(2DEG)channel.The fabricated E-mode HEMTs exhibit a relatively high threshold voltage(VTH)of+1.1 V with good uniformity.A maxi-mum current/power gain cut-off frequency(fT/fMAX)of 31.3/99.6 GHz with a power added efficiency(PAE)of 52.47%and an out-put power density(Pout)of 1.0 W/mm at 3.5 GHz were achieved on the fabricated E-mode HEMTs with 1-μm gate and Au-free ohmic contact.

11.2 W/mm power density AlGaN/GaN high electron-mobility transistors on a GaN substrate

In this letter,high power density AlGaN/GaN high electron-mobility transistors(HEMTs)on a freestanding GaN substrate are reported.An asymmetricΓ-shaped 500-nm gate with a field plate of 650 nm is introduced to improve microwave power performance.The breakdown voltage(BV)is increased to more than 200 V for the fabricated device with gate-to-source and gate-to-drain distances of 1.08 and 2.92μm.A record continuous-wave power density of 11.2 W/mm@10 GHz is realized with a drain bias of 70 V.The maximum oscillation frequency(f_(max))and unity current gain cut-off frequency(f_(t))of the AlGaN/GaN HEMTs exceed 30 and 20 GHz,respectively.The results demonstrate the potential of AlGaN/GaN HEMTs on freestanding GaN substrates for microwave power applications.

Effects of unilateral superimposed high-frequency jet ventilation on porcine hemodynamics and gas exchange during one-lung flooding

BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is necessary for therapeutic ultrasound applications.However,whether unilateral SHFJV allows adequate hemodynamics and gas exchange is unclear.AIM To compared SHFJV with pressure-controlled ventilation(PCV)during OLF by assessing hemodynamics and gas exchange in different animal positions.METHODS SHFJV or PCV was used alternatingly to ventilate the non-flooded lungs of the 12 anesthetized pigs during OLF.The animal positions were changed from left lateral position to supine position(SP)to right lateral position(RLP)every 30 min.In each position,ventilation was maintained for 15 min in both modalities.Hemodynamic variables and arterial blood gas levels were repeatedly measured.RESULTS Unilateral SHFJV led to lower carbon dioxide removal than PCV without abnormally elevated carbon dioxide levels.SHFJV slightly decreased oxygenation in SP and RLP compared with PCV;the lowest values of PaO_(2) and PaO_(2)/FiO_(2) ratio were found in SP[13.0;interquartile range(IQR):12.6-5.6 and 32.5(IQR:31.5-38.9)kPa].Conversely,during SHFJV,the shunt fraction was higher in all animal positions(highest in the RLP:0.30).CONCLUSION In porcine model,unilateral SHFJV may provide adequate ventilation in different animal positions during OLF.Lower oxygenation and CO_(2) removal rates compared to PCV did not lead to hypoxia or hypercapnia.SHFJV can be safely used for lung tumor ablation to minimize ventilation-induced lung motion.

Therapeutic efficacy of methylprednisolone sodium succinate via diverse administration routes for mid-to high-frequency sudden sensorineural hearing loss

BACKGROUND Sudden sensorineural hearing loss(SSNHL),characterized by a rapid and unexplained loss of hearing,particularly at moderate to high frequencies,presents a significant clinical challenge.The therapeutic use of methylprednisolone sodium succinate(MPSS)via different administration routes,in combination with conventional medications,remains a topic of interest.AIM To compare the therapeutic efficacy of MPSS administered via different routes in combination with conventional drugs for the treatment of mid-to high-frequency SSNHL.METHODS The medical records of 109 patients with mid-to high-frequency SSNHL were analyzed.The patients were divided into three groups based on the route of administration:Group A[intratympanic(IT)injection of MPSS combined with mecobalamin and Ginkgo biloba leaf extract injection],Group B(intravenous injection of MPSS combined with mecobalamin and Ginkgo biloba leaf extract injection),and Group C(single IT injection of MPSS).The intervention effects were compared and analyzed.RESULTS The posttreatment auditory thresholds in Group A(21.23±3.34)were significantly lower than those in Groups B(28.52±3.36)and C(30.23±4.21;P<0.05).Group A also exhibited a significantly greater speech recognition rate(92.23±5.34)than Groups B and C.The disappearance time of tinnitus,time to hearing recovery,and disappearance time of vertigo in Group A were significantly shorter than those in Groups B and C(P<0.05).The total effective rate in Group A(97.56%)was significantly greater than that in Groups B and C(77.14%and 78.79%,χ^(2)=7.898,P=0.019).Moreover,the incidence of adverse reactions in Groups A and C was significantly lower than that in Group B(4.88%,3.03%vs 2.57%,χ^(2)=11.443,P=0.003),and the recurrence rate in Group A was significantly lower than that in Groups B and C(2.44%vs 20.00%vs 21.21%,χ^(2)=7.120,P=0.028).CONCLUSION IT injection of MPSS combined with conventional treatment demonstrates superior efficacy and safety compared to systemic administration via intravenous infusion and a single IT injection of MPSS.This approach effectively improves patients'hearing and reduces the risk of disease recurrence.

Split Addition of Nitrogen-Rich Substrate at Thermophilic and Mesophilic Stages of Composting: Effect on Green House Gases Emission and Quality of Compost

Composting as a solution to the increasing generation of municipal solid waste (MSW), also contribute to GHGs emission when not controlled and could lack some basic nutrients, especially nitrogen. This study assessed the split-additions of nitrogen-rich substrate to composting materials and their effect on GHGs emissions as well as the quality of the composts. Nitrogen-rich substrates formulated from pig and goat manure were co-composted with MSW for a 12-weeks period by split adding at mesophilic (˚C) and thermophilic (>50˚C) stages in five different treatments. Representative samples from the compost were taken from each treatment for physicochemical, heavy metals and bacteriological analysis. In-situ CH4, CO2, N2O gas emissions were also analyzed weekly during composting. It was observed that all the treatments showed significant organic matter decomposition, reaching thermophilic temperatures in the first week of composting. The absence affects the suitable agronomic properties. All nitrogen-rich substrate applied at thermophilic stage (Treatment two) recorded the highest N, P and K concentrations of 1.34%, 0.97% and 2.45%, respectively with highest nitrogen retention. In terms of GHG emissions, CO2 was highest at the thermophilic stage when N-rich substrate was added in all treatment, while CH4 was highest in the mesophilic stage with N-rich substrate addition. N2O showed no specific trend in the treatments. Split addition of the N-rich substrate for co-composting of MSW produced compost which is stable, has less nutrient loss and low GHG emissions. Split addition of a nitrogen-rich substrate could be an option for increasing the fertilizer value of MSW compost.

Effect of Frequency and Power of Bias Applied to Substrate on Plasma Property of Very-High-Frequency Magnetron Sputtering

The effect of the frequency and power of the bias applied to the substrate on plasma properties in 60 MHz（VHF） magnetron sputtering was investigated.The plasma properties include the ion velocity distribution function（IVDF）,electron energy probability function（EEPF）,electron density ne,ion flux Γi,and effective electron temperature Teff.These parameters were measured by a retarding field energy analyzer and a Langmuir probe in the 60 MHz magnetron sputtering,assisted with 13.56 MHz or 27.12 MHz substrate bias.The 13.56 MHz substrate bias led to broadening and multi-peaks IVDFs,Maxwellian EEPFs,as well as high electron density,ion flux,and low electron temperature.The 27.12 MHz substrate bias led to a further increase of electron density and ion flux,but made the IVDFs narrow.Therefore,the frequency of the substrate bias was a possible way to control the plasma properties in VHF magnetron sputtering.

Advances in the structure design of substrate materials for zinc anode of aqueous zinc ion batteries

Aqueous zinc ion batteries(AZIBs) demonstrate tremendous competitiveness and application prospects because of their abundant resources,low cost, high safety, and environmental friendliness. Although the advanced electrochemical energy storage systems based on zinc ion batteries have been greatly developed, many severe problems associated with Zn anode impede its practical application, such as the dendrite formation,hydrogen evolution, corrosion and passivation phenomenon. To address these drawbacks, electrolytes, separators, zinc alloys, interfacial modification and structural design of Zn anode have been employed at present by scientists. Among them, the structural design for zinc anode is relatively mature, which is generally believed to enhance the electroactive surface area of zinc anode, reduce local current density, and promote the uniform distribution of zinc ions on the surface of anode. In order to explore new research directions, it is crucial to systematically summarize the structural design of anode materials. Herein, this review focuses on the challenges in Zn anode, modification strategies and the three-dimensional(3D) structure design of substrate materials for Zn anode including carbon substrate materials, metal substrate materials and other substrate materials. Finally, future directions and perspectives about the Zn anode are presented for developing high-performance AZIBs.

Phytochemical Contents and Antioxidant Properties of Ganoderma lucidum Polysaccharides in Relation to Growth Stage and Culture Substrate

[Objectives]To determine physicochemical characteristics and antioxidant activity of Ganoderma lucidum polysaccharides(GLP)in different growth stages and culture media.[Methods]Five polysaccharides(GLP1,GLP2,GLP3,GLPW and GLPB)were extracted and purified from the fruiting body of G.lucidum at three growth stages and culture substrates(wood culture and bag culture).The chemical components and antioxidant activity of the five polysaccharides were determined.[Results]GLP1 contained the highest content of neutral sugar(87.65%)and GLP3 had the highest uronic acid content.All the samples mainly comprised glucose,galactose,mannose,xylose and arabose with different ratios.Moreover,their antioxidant activities were investigated on the basis of DPPH radical,ABTS radical,SOD-like activity,and antihaemolytic activity.Results indicated in all three growth stages GLP2 had the greatest antioxidant properties.In addition,the antioxidant activity of GLPW was significantly higher than that of GLPB.[Conclusions]Overall,by comparison,G.lucidum in growth stage two may have potential health benefits,and wood culture may be a superior choice of artificial cultivation due to their abundance of active polysaccharides.

Radio-frequency measurements of energetic-electron-driven emissions using high-frequency magnetic probe on XuanLong-50 spherical torus

A high-frequency magnetic probe is designed and developed on the XuanL ong-50(EXL-50)spherical torus to measure high-frequency magnetic field fluctuation.The magnetic loop,radio filters,radio-frequency limiter,and data acquisition system of the probe are comprehensively examined.The fluctuation data from the EXL-50 plasma are analyzed in the time–frequency domain using fast Fourier transforms.Moreover,distinct high-frequency instabilities are detected using this diagnostic system.In particular,significant frequency chirping is observed,which is consistent with the bumpon-tail drive instability predicted using the Berk–Breizman model.

Effects of substrate on burrowing behavior,feeding physiology,and energy budget of undulated surf clam Paphia undulata

Substrate is an important abiotic factor for burrowing shellfish,as it not only provides them with shelter,but also impose significant effect on their physiological metabolism.However,the physiological responses of burrowing clams within various substrates get less attention due to difficulty in carrying out physiological tests in buried conditions.Consequently,this study investigated the burrowing behavior,feeding physiology and energy budget of Paphia undulata,which is an important aquaculture bivalve species in south China.The clams were exposed to mud and sand substrates with variable physical properties in the laboratory,to determine the suitable substrate conditions for this species.The results showed that the percentage of burrowing clams,digging index,burrowing time,burrowing depth and scope for growth(SFG)were higher in mud substrates with≥40%water content.Likewise,burrowing percentage,digging index,and burrowing depths were higher in substrates with≤40%sand content.Moreover,the burrowing depth had significant effect on the feeding physiology and SFG of P.undulata as clams burrowed at 6.3±1.8 cm had higher clearance rates and SFG as compared to other buried depths.This study further revealed that low water content in the sediment inhibited physiological performances of P.undulata by impairing feeding or absorption,hence reducing the SFG.In conclusion,mud substrate with≥40%water content or with≤40%sand content is suitable for proper burrowing and growth of P.undulata.Our findings therefore provide fundamental knowledge that will be applicable in the improvement of bottom aquaculture and conservation of P.undulata.

Microbiota of a seepage face at the mouth of a subterranean estuary:diversity,distribution and substrate dependence

Subterranean estuaries,i.e.,the mixing zone between terrestrial groundwater and recirculated seawater,host a wide range of microbiota.Here,field campaigns were conducted at the mouth of the subterranean estuary at the Sanggou Bay(Shandong Province,China)over four consecutive seasons at a seepage face(0−20 cm depth).The diversity of benthic microbiome was characterized via 16S rRNA gene sequencing and metagenomics,combined with physic-chemical parameters,e.g.,organic carbon,total nitrogen and sulfate contents in sediments.During spring,the dominant species were assigned to the phylum Proteobacteria.Important opportunistic species was assigned to Acidobacteria,Actinobacteria and Bacteroidetes.The key components were identified to be species of the genera Pseudoalteromonas,Colwellia and Sphingobium,indicating the involvement of sediment microbiota in the degradation of sedimentary organic carbon,particularly that of pelagic origin,e.g.,phytoplankton detritus and bivalve pseudo-feces.During spring,the microbial community was statistically similar along the depth profiles and among the three sampled stations.Similar spatial distributions were obtained in the remaining seasons.By contrast,the dominant species assemblages varied significantly among seasons,with key genera being Thioprofundum and Nitrosopumilus during summer and autumn and Thioprofundum and Ilumatobacter during winter.Network analysis revealed a seasonal shift in benthic nitrogen and sulfur metabolism associated with these variations in microbial community composition.Overall,our findings suggested that macro elements derived from pelagic inputs,particularly detrital phytoplankton,shaped the microbial community compositions at the seepage face,resulting in significant seasonal variations,while the influence of terrestrial materials transported by groundwater on the sediment microbiota at the seepage face found to be minor.

Substrate,Hormone,Winnowing,and Stratification Influence the Seed Germination of Ilex asprella(Hook.et Arn.)Champ.ex Benth

Ilex asprella(Hook.et Arn.)Champ.ex Benth is one of the most important traditional Chinese medicines in southern China.The seeds of Ilex asprella usually have extremely low germination due to their dormancy characteristics,which severely impacts the efficiency of seedling raising and increases labor costs.In this study,to improve the seed germination of I.asprella,the effects of germination substrate,hormone,winnowing,and stratification treatments on the seed germination of I.asprella were investigated.The results of the germination matrix showed that the highest germination percentage of 45.2%was achieved under the 20℃/10℃day/night temperature and vermiculite germination medium conditions.The results of hormone treatments revealed that 100–400 mg/L of gibberellin(GA)and 50–100 mg/L of salicylic acid(SA)were found to be effective in releasing the dormancy of I.asprella seeds.Moreover,winnowing could effectively eliminate unsaturated seeds and impurities,thus improving the seed germination of I.asprella.Furthermore,warm temperature(15℃)stratification could expand the temperature range of I.asprella’s seed germination,which was beneficial for seed germination of I.asprella and for seed nursery at room temperature in production practice.The present study obtained a method to break dormancy and increase seed germination in I.asprella,thereby forming a groundwork for improving the efficiency of large-scale planting of I.asprella.

Effect of Two Substrate Types on Feeding Efficiency by Juvenile Chinese Sturgeon Acipenser sinensis on Barcheek Goby Rhinogobius giurinus

We conducted experiments in an artificial stream tank with wild juvenile Chinese sturgeon Acipenser sinensis captured in the Yangtze Estuary to test the null hypothesis that their feeding efficiency on Barcheek goby Rhinogobius giurinus was not affected by sand vs. smooth glass substrate. Gobies are among the most common prey eaten by wild juvenile A. sinensis in the estuary. Test results found neither substrate type significantly affected feeding efficiency by juveniles. Previous research found a strong innate habitat preference of A. sinensis for sand substrate. The present results indicate that the preference for sand is not related to efficiently capturing R. giurinus on sand, but is an adaptation predisposing juvenile A. sinensis to seek sandy substrate where R. giurinus and other benthic forage are the most abundant in the Yangtze Estuary.

Tuning magneto-dielectric properties of Co_(2)Z ferrites via Gd doping for high-frequency applications

Magneto-dielectric properties of Co_(2)Z ferrite materials are tuned via Gd doping for applications in high-frequency antennas and filters in the present work.Ba_(3)Co_(2)Fe_(24-x)Gd_(x)O_(41)(x=0.00,0.05,0.10,0.15,and 0.20)materials are successfully prepared by using solid-state method at 925℃for 4 h with 2.5-wt%Bi_(2)O_(3)sintering aids.The content of Gd^(3+)ion can affect micromorphology,grain size,bulk density,and magneto-dielectric properties of the ferrite.With Gd^(3+)ion content increasing,saturation magnetization(Ms)first increases and then decreases.The maximum value of Ms is 44.86 emu/g at x=0.15.Additionally,sites occupied by Gd^(3+)ions can change magnetic anisotropy constant of the ferrite.Magnetocrystalline anisotropy constant(K_1)is derived from initial magnetization curve,and found to be related to spin-orbit coupling and intersublattice interactions between metal ions.The real part of magnetic permeability(μ′)and real part of dielectric permittivity(ε′)are measured in a frequency range of 10 MHz-1 GHz.When x=0.15,material has excellent magneto-dielectric properties(μ′≈12.2 andε′≈17.61),low magnetic loss(tanδμ≈0.03 at 500 MHz),and dielectric loss(tanδε≈0.04 at 500 MHz).The results show that Gd-doped Co_(2)Z ferrite has broad application prospects in multilayer filters and high-frequency antennas.

Evaluation of Different Substrates Compositions for Acclimatization of Tissue Culture Taro Plantlets in a Propagator

Taro is cultivated in most Regions of Cameroon and it is affected by taro leaf blight disease since 2010 which has decreased its production. Lack of disease-free planting materials has been a main problem to farmers. This study was carried out at International Institute of Tropical Agriculture (IITA) Yaounde and Institute of Agricultural Research for Development (IRAD) Bambui to assess different substrates for acclimatization of tissue culture taro plantlets in apropagator. No information is available on acclimatization of Cameroonian taro plantlets in different substrates. Taro plantlets from tissue culture were acclimatised in a propagator for six weeks under different substrates, the first substrate consisted of sterile three parts of soil and one part of river sand mixed together (3:1), the second substrate consisted of sterile two parts of soil and two parts of river sand mixed together (2:2), the third substrate consisted of sterile two parts of soil, one part of rice husk and one part of river sand mixed together (2:1:1) and the fourth substrate consisted of sterile one part of soil and three parts of river sand mixed together (1:3). After acclimatisation of the different taroplantlets (Dark green petiole with small leaves (L1), Red petiole with small leaves (L2), Light green petiole with large leaves (L3) and Light green petiole with small leaves (L4) in these four substrates, it was observed that the best growth rate of plant was recorded on substrate sand + soil (1:3). The other substrates showed moderate growth of plants. Substrate sand + soil (1:3) can be recommended for acclimatization of Cameroonian taro plantlets.