Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_...Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_(3) content,and have not been widely utilized in the synthesis of HA.This study aims to synthesize and analyze HA derived from crab shells using the hydrothermal method with different durations of holding time.This study utilized precipitated calcium carbonate(PCC)derived from crab shells.With a hydrothermal reactor set at 160℃ and varying holding times of 14(HA_14),16(HA_16),and 18(HA_18)h,a PCC and(NH4)2HPO4 mixture was used to synthesize HA.The synthesis results were analyzed using scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD)tests.This study has accomplished the synthesis of HA from crab shells.Nonetheless,the final product of synthesis still contained CaCO_(3) as an impurity.The prolonged hydrothermal holding time of 14 to 18 h resulted in a reduction of impurities while increasing the percentage of crystal weight and crystallite size of HA.Specimen CH_18 is the best-quality product generated in this study.This specimen produced HA with the highest percentage of crystal weight and crystallite size compared to the other specimens.Furthermore,specimen CH_18 exhibited the lowest concentration of impurities.The Ca/P ratio in this specimen was also the closest to 1.67.The Ca/P ratio,crystallite size,and crystal weight percentage of this specimen are 1.54,19.06 nm,and 99.1%,respectively.展开更多
采用废弃蟹壳为碳源,KOH为活化剂原位制备了氮/氧共掺杂多孔炭,并研究其作为电极材料在超级电容器中的应用。固定蟹壳与KOH的质量比为5∶3,考察了煅烧温度对所得炭材料产率、孔结构和氮氧含量的影响。结果表明,蟹壳基炭材料的孔结构和氮...采用废弃蟹壳为碳源,KOH为活化剂原位制备了氮/氧共掺杂多孔炭,并研究其作为电极材料在超级电容器中的应用。固定蟹壳与KOH的质量比为5∶3,考察了煅烧温度对所得炭材料产率、孔结构和氮氧含量的影响。结果表明,蟹壳基炭材料的孔结构和氮/氧含量可通过改变煅烧温度调变。随着煅烧温度从500℃上升至700℃,多孔炭的比表面积和孔体积逐渐增大,而氮/氧含量随温度升高则降低。采用循环伏安和恒流充放电对所得材料的电化学性能进行测试。结果表明,所得多孔炭的电化学性能取决于其孔结构与氮/氧表面性质的协同作用,其中煅烧温度为600℃所得的多孔炭比表面积为612 m^2/g,氮和氧含量分别为3.53%和32.8%,在50 m A/g的电流密度下比电容达到310 F/g,循环1000次比电容仍然保持95%以上,展现出良好的电化学性能。展开更多
Crab shells are an important feedstock for chitin production.However,their highly compact structure significantly limits their use for the production of chitin under mild conditions.Here,a green and efficient approach...Crab shells are an important feedstock for chitin production.However,their highly compact structure significantly limits their use for the production of chitin under mild conditions.Here,a green and efficient approach using a natural deep eutectic solvent(NADES)to produce chitin from crab shells was developed.Its effectiveness in isolating chitin was investigated.The results showed that most proteins and minerals were removed from crab shells and the relative crystallinity of the isolated chitin reached 76%.The quality of the obtained chitin was comparable to chitin isolated by the acid–alkali method.This is the first report on a green method for efficient chitin production from crab shells.This study is expected to open new avenues for green and efficient production of chitin from crab shells.展开更多
采用胶体几丁质平板产生透明圈法,从竹林附近的土壤中分离得到一株高产几丁质酶的优良菌株,以胶体几丁质为反应底物,对其所产的几丁质酶粗酶性质进行了初步研究。结果表明,该酶最适p H 7.5,在p H 6.5~9.5的缓冲液中放置12 h后,残余酶活...采用胶体几丁质平板产生透明圈法,从竹林附近的土壤中分离得到一株高产几丁质酶的优良菌株,以胶体几丁质为反应底物,对其所产的几丁质酶粗酶性质进行了初步研究。结果表明,该酶最适p H 7.5,在p H 6.5~9.5的缓冲液中放置12 h后,残余酶活仍在60%以上,在p H 7.0~8.5的缓冲液中残余酶活仍在80%以上,说明该酶在中性和碱性条件下具有较好的稳定性;该酶在30℃时酶活最高,在低于60℃的处理条件下残余酶活仍在80%以上,且80℃处理后仍有37%的残余酶活,说明该酶的热稳定性较好;配制蟹壳培养基发酵该菌,发现该菌能直接降解蟹壳产生壳寡糖,且每克蟹壳降解后可产生5.3 mg还原糖。通过16S r DNA基因序列比对,鉴定该菌为芽孢杆菌属(Bacillus sp.)。展开更多
基金funded the World Class Research(WCR)Grant of Universitas Diponegoro with Contract Number 357-36/UN7.D2/PP/IV/2024.
文摘Hydroxyapatite(HA)is a bio ceramic commonly utilized in bone tissue engineering due to its bioactive and osteoconductive properties.Crab shells are usually disregarded as waste material despite their significant CaCO_(3) content,and have not been widely utilized in the synthesis of HA.This study aims to synthesize and analyze HA derived from crab shells using the hydrothermal method with different durations of holding time.This study utilized precipitated calcium carbonate(PCC)derived from crab shells.With a hydrothermal reactor set at 160℃ and varying holding times of 14(HA_14),16(HA_16),and 18(HA_18)h,a PCC and(NH4)2HPO4 mixture was used to synthesize HA.The synthesis results were analyzed using scanning electron microscopy(SEM),fourier transform infrared spectroscopy(FTIR),and X-ray diffraction(XRD)tests.This study has accomplished the synthesis of HA from crab shells.Nonetheless,the final product of synthesis still contained CaCO_(3) as an impurity.The prolonged hydrothermal holding time of 14 to 18 h resulted in a reduction of impurities while increasing the percentage of crystal weight and crystallite size of HA.Specimen CH_18 is the best-quality product generated in this study.This specimen produced HA with the highest percentage of crystal weight and crystallite size compared to the other specimens.Furthermore,specimen CH_18 exhibited the lowest concentration of impurities.The Ca/P ratio in this specimen was also the closest to 1.67.The Ca/P ratio,crystallite size,and crystal weight percentage of this specimen are 1.54,19.06 nm,and 99.1%,respectively.
文摘采用废弃蟹壳为碳源,KOH为活化剂原位制备了氮/氧共掺杂多孔炭,并研究其作为电极材料在超级电容器中的应用。固定蟹壳与KOH的质量比为5∶3,考察了煅烧温度对所得炭材料产率、孔结构和氮氧含量的影响。结果表明,蟹壳基炭材料的孔结构和氮/氧含量可通过改变煅烧温度调变。随着煅烧温度从500℃上升至700℃,多孔炭的比表面积和孔体积逐渐增大,而氮/氧含量随温度升高则降低。采用循环伏安和恒流充放电对所得材料的电化学性能进行测试。结果表明,所得多孔炭的电化学性能取决于其孔结构与氮/氧表面性质的协同作用,其中煅烧温度为600℃所得的多孔炭比表面积为612 m^2/g,氮和氧含量分别为3.53%和32.8%,在50 m A/g的电流密度下比电容达到310 F/g,循环1000次比电容仍然保持95%以上,展现出良好的电化学性能。
基金supported by China Agriculture Research System(CARS-48)Taishan Scholar Project of Shandong Province(tsqn201812020)Fundamental Research Funds for the Central Universities(201941002).
文摘Crab shells are an important feedstock for chitin production.However,their highly compact structure significantly limits their use for the production of chitin under mild conditions.Here,a green and efficient approach using a natural deep eutectic solvent(NADES)to produce chitin from crab shells was developed.Its effectiveness in isolating chitin was investigated.The results showed that most proteins and minerals were removed from crab shells and the relative crystallinity of the isolated chitin reached 76%.The quality of the obtained chitin was comparable to chitin isolated by the acid–alkali method.This is the first report on a green method for efficient chitin production from crab shells.This study is expected to open new avenues for green and efficient production of chitin from crab shells.
文摘采用胶体几丁质平板产生透明圈法,从竹林附近的土壤中分离得到一株高产几丁质酶的优良菌株,以胶体几丁质为反应底物,对其所产的几丁质酶粗酶性质进行了初步研究。结果表明,该酶最适p H 7.5,在p H 6.5~9.5的缓冲液中放置12 h后,残余酶活仍在60%以上,在p H 7.0~8.5的缓冲液中残余酶活仍在80%以上,说明该酶在中性和碱性条件下具有较好的稳定性;该酶在30℃时酶活最高,在低于60℃的处理条件下残余酶活仍在80%以上,且80℃处理后仍有37%的残余酶活,说明该酶的热稳定性较好;配制蟹壳培养基发酵该菌,发现该菌能直接降解蟹壳产生壳寡糖,且每克蟹壳降解后可产生5.3 mg还原糖。通过16S r DNA基因序列比对,鉴定该菌为芽孢杆菌属(Bacillus sp.)。
