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1.
Sci Total Environ ; 859(Pt 1): 160196, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36403841

RESUMO

Plant root growth significantly affect soil detachment process, whereas the mechanism of how roots affect the soil detachment process by overland flow at species level is not fully understood. This study was conducted to investigate the soil detachment rate responds to plant-induce soil properties and root traits at species level. Two typical herbaceous plants, Bothriochloa ischcemum (Linn.). Keng (BI; fibrous root system) and Artemisia vestita Wall. ex Bess (AG; tap root system), from the Loess Plateau were studies for one year under six planted densities of 5 plants m-2, 10 plants m-2, 15 plants m-2, 20 plants m-2, 25 plants m-2, and 30 plants m-2. In total, 24 steel tanks were planted, and two plots were used as bare soil controls. Their soil detachment rates were tested under a constant overland flow (1.5 l s-1) on a 26.2 % slope. The results showed that soil detachment rate under the six planted densities ranged from 0.034 kg m2 s-1 to 0.112 kg m2 s-1 for BI and was ranged from 0.053 kg m2 s-1 to 0.132 kg m2 s-1 for AG, which all greatly reduced soil detachment rate and were 68.17 % to 92.33 % and 69.20 % to 87.27 % less than that of the control. In general, BI was more effective in reducing soil detachment rate than AG, achieving a mean soil detachment rate that was 23.75 % lower. With increasing plant density, soil detachment rate decreased as a power function. The overland flow hydraulic characteristics, soil properties and root traits influenced by plant density were positively or negatively correlated with soil detachment rate. Specifically, soil detachment rate decreased with velocity, bulk density, root length density, and increased with shear stress and Darcy-Weisbach friction factor as power or exponential functions. On this basis, the soil detachment rate (Dr) can be satisfactorily estimated by overland flow velocity (v), soil bulk density (BD) and root length density (RLD) as a power function (Dr = 63.03v0.174 × BD-20.712 × RLD-0.233R2 = 0.65; NSE = 0.60; p < 0.01).


Assuntos
Raízes de Plantas , Solo , Poaceae , Plantas
2.
Medicine (Baltimore) ; 101(33): e30099, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-35984168

RESUMO

BACKGROUND: Epidermal growth factor receptor (EGFR)-mutant nonsmall cell lung cancer (NSCLC) patients are less likely to be programmed death-ligand 1 (PD-L1)-positive compared with wild-type EGFR mutant tumors. Given the rarity of actionable driver genes in squamous cell lung cancer (SQCC), the frequency of SQCC patients simultaneously carrying EGFR driver gene mutation and having PD-L1 over-expression is extremely low. Studies on the effectiveness and safety of EGFR-TKIs or immune-checkpoint inhibitors (ICIs) in this subset of patients are lacking. PATIENT CONCERNS: The patient suffered from coughing and chest pain for 1 month. A chest CT revealed a mass with a cavity in the right lung, enlarged mediastinal lymph nodes, diffuse pleural thickening in the right pleura, and pleural effusion of the right chest. DIAGNOSIS: A pleural biopsy was performed using a video-assisted thoracoscope. The pathological examination revealed a poorly differentiated squamous cell carcinoma of lung. Further genetic testing identified exon 19 deletion mutation in EGFR with abundance of 0.27%. Meanwhile, immunohistochemical PD-L1 analysis showed a TPS of 90%. INTERVENTIONS: The patient was initially resistant to EGFR-TKIs but exhibited a rapid and marked response to pembrolizumab. OUTCOMES: After 5 cycles of pembrolizumab monotherapy, the patient developed Grade 3 immune-related dermatitis, and ICI therapy was suspended. CONCLUSIONS: ICI monotherapy could be an effective therapy in SQCC patients with low-abundance of EGFR mutations and PD-L1 over-expression. However, close attention should be paid to immune-related adverse events.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Anticorpos Monoclonais Humanizados , Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Células Epiteliais/patologia , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Mutação
3.
Int J Biol Macromol ; 216: 32-41, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35777504

RESUMO

The cAMP response element binding protein 1 (CREB1) is an important nuclear transcription factor in eukaryotes. To explore the potential role of CREB1 on Qinchuan bovine skeletal myoblasts, we investigated the function of CREB1 on proliferation and differentiation. In this study, we found that CREB1 promoted cell proliferation by promoting DNA synthesis in S phase and cell division in G2 phase and promoted myogenic differentiation process in bovine myoblasts. Through dual luciferase experiments, we found that CREB1 can bind to the proximal promoter regions of CCNA2 and MyoG, indicating that CREB1 can play a positive regulatory role in the proliferation and differentiation of myoblasts by mediating the transcription of CCNA2 and MyoG. In addition, through downstream target gene analysis and transcriptome sequencing, we found that CREB1 plays a role in cell proliferation, myogenic differentiation, skeletal muscle repair and other related pathways.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Mioblastos Esqueléticos , Animais , Bovinos , Diferenciação Celular/genética , Proliferação de Células/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Desenvolvimento Muscular/genética
4.
Huan Jing Ke Xue ; 42(7): 3422-3429, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212669

RESUMO

Cold acclimation is an effective approach for improving the nitrogen removal performance and operational stability of partial nitritation/ANAMMOX (PN/A) combined processes at low temperatures. To explore the specific effects of cold acclimation on the characteristics of sludge, differentiations in temperature sensitivity, granular morphology, composition of extracellular polymer substance (EPS), and bacterial community structure between PN/A granular sludges cultivated at medium-high temperature (30℃) and acclimated to low temperature (15℃) were investigated in this study. The results of reaction thermodynamics showed that the nitrogen removal performance of the granules acclimated to low temperature (GL) was significantly higher than that of those cultivated at medium-high temperature (GH) under the low temperature (10-20℃), and the apparent activation energy (Ea) of total inorganic nitrogen removal for the former was decreased by 28.4%. Compared with GH, GL had a smaller average particle size of 25.8% and higher EPS contents of 16.6%, resulting in a significant lower settling property. Based on the high-throughput sequencing results, GL exhibited a higher diversity of bacterial community, and a lower relative abundance ratio (0.04) of aerobic ammonium-oxidizing bacteria (Nitrosomonas) and anaerobic ammonium-oxidizing bacteria (Candidatus_Kuenenia) than 0.34 for GH. It indicated that the PN/A granules held a strong ability to retain slow-growing autotrophic bacteria in the system, even under low temperatures. These findings could provide meaningful references for analyzing the self-adaption mechanisms of PN/A sludge to low temperature conditions and promote the industrial application of combined processes.


Assuntos
Nitrogênio , Esgotos , Aclimatação , Reatores Biológicos , Desnitrificação , Nitrogênio/análise , Oxirredução
5.
J BUON ; 26(1): 296, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33721481

RESUMO

The Editors of JBUON issue an Expression of Concern to 'Amarogentin secoiridoid inhibits in vivo cancer cell growth in xenograft mice model and induces apoptosis in human gastric cancer cells (SNU-16) through G2/M cell cycle arrest and PI3K/Akt signalling pathway', by Jian-Guo Zhao, Ling Zhang, Xiao-Jun Xiang, Feng Yu, Wan-li Ye, Dong-Ping Wu, Jian-Fang Wang, Jian-Ping Xiong, JBUON 2016;21(3):609-617; PMID:27569081. Following the publication of the above article, readers drew to our attention that part of the data was possibly unreliable. We sent emails to the authors with a request to provide the raw data to prove the originality, but received no reply. Therefore, as we continue to work through the issues raised, we advise readers to interpret the information presented in the article with due caution. We thank the readers for bringing this matter to our attention. We apologize for any inconvenience it may cause.

6.
Medicine (Baltimore) ; 99(51): e23806, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33371156

RESUMO

BACKGROUND: Functional constipation (FC) is a common gastrointestinal disorder characterized by slow bowel movement and defecation difficulties, significantly impacting patients' quality of life and exerting heavy financial burden to whole society. However, more than 50% FC patients are not completely satisfied with current therapies and alternative therapies are urgently required. Increasing evidences have demonstrated that traditional Chinese medicine has a good therapeutic effect on FC, which is well known for its multitarget and multimode effects on diverse diseases as well as less side effects. Furthermore, studies proved that Qi Di Laxative Decoction was an effective treatment for FC. Its safety and effectiveness should be verified by further studies. METHODS: We will search the following electronic databases for randomized controlled trials to evaluate the clinical efficacy of Qi Di Laxative Decoction in treating FC: Wanfang and Pubmed Database, China National Knowledge Infrastructure Database, Cochrane Central Register of Controlled Trials, Cumulative Index of Nursing and Allied Health Literature, and Excerpta Medica database. Each database will be searched from inception to November 2020. The entire process will include study selection, data extraction, risk of bias assessment, and meta-analyses. RESULTS: This proposed study will evaluate the clinical efficacy of Qi Di Laxative Decoction for patients with FC. The outcomes will include changes in FC relief and adverse effect. CONCLUSION: This proposed systematic review will evaluate the existing evidence on the clinical efficacy of Qi Di Laxative Decoction in treating FC. DISSEMINATION AND ETHICS: The results of this review will be disseminated through peer-reviewed publication. Because all of the data used in this systematic review and meta-analysis has been published, this review does not require ethical approval. Furthermore, all data will be analyzed anonymously during the review process. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/M2ESR.


Assuntos
Protocolos Clínicos , Constipação Intestinal/tratamento farmacológico , Laxantes/normas , Medicina Tradicional Chinesa/normas , Humanos , Laxantes/uso terapêutico , Medicina Tradicional Chinesa/métodos , Metanálise como Assunto , Revisões Sistemáticas como Assunto , Resultado do Tratamento
7.
Huan Jing Ke Xue ; 41(9): 4161-4168, 2020 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124298

RESUMO

A single-stage PN-ANAMMOX (PN/A) granular sludge cultured at room temperature was used to investigate the completely autotrophic nitrogen removal efficiency and microbial community structure of low-strength wastewater based on the completely autotrophic nitrogen removal over nitrite in granular sludge at a low temperature. The results showed that at the low temperature (15±1)℃, the ammonia nitrogen load was maintained at 1.29 kg ·(m3 ·d)-1, and the ammonia nitrogen concentration in the injection was gradually reduced from 70 mg ·L-1 to 40 mg ·L-1. DO/TAN was controlled at 0.22-0.25. The total nitrogen removal rate was maintained at (85±4)%, and the average TN concentration in the effluent was 8.9 mg ·L-1. There was no significant proliferation of nitrite-oxidizing bacteria (NOB) during the operation period, and the Nitrospira abundance was less than 1%. Elutriation of the floc sludge and the control of low DO/TAN values can be used as effective control strategies to inhibit NOB proliferation. Through completely autotrophic nitrogen removal over nitrite in granular sludge operated under low-temperature and low-substrate conditions, the particle size became smaller, and the color changed from brown red to brown yellow. The total amount of PS decreased slightly, and the ratio of PN/PS stabilized at 2.5-3.0. Planctomycetes and Proteobacteria dominated the community, and Candidatus_Kuenenia and Candidatus_Brocadia were two AMX bacteria in the sludge.


Assuntos
Nitrogênio , Esgotos , Reatores Biológicos , Desnitrificação , Oxirredução , Temperatura
8.
Huan Jing Ke Xue ; 41(10): 4653-4660, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124398

RESUMO

A rapid start of the completely autotrophic nitrogen removal over nitrite (CANON) process based on granular sludge and efficient nitrogen removal under mixotrophic conditions are important steps in a continuous flow reactor for CANON engineering applications. In this study, an aged CANON granular sludge was mechanically crushed to 0.3 mm as inoculum in an airlift internal-loop reactor (AIR) to achieve simultaneous COD removal and mixotrophic denitrification of the single-stage granular sludge. The system achieved stable partial nitrification by controlling DO after 26 days of startup. Granulation and anaerobic ammonia oxidation were then promoted by shortening the HRT to increase the ammonia nitrogen load to 5.65 kg ·(m3 ·d)-1. The total nitrogen removal rate reached 58% on the 68th day. Subsequently, the C/N ratio of influent was increased from 0 to 0.25 and 0.5, which promoted the synergistic growth of AOB, AMX, and heterotrophic microorganisms. The removal rates of ammonia and total nitrogen were 95% and 85% respectively, and the removal of COD reached approximately 80%. The activity of NOB such as Nitrospira was effectively inhibited as the COD concentration was increased. q(NH4+-N) and q(TN) were stable at 0.4 g ·(g ·h)-1 and 0.34 g ·(g ·h)-1, respectively, while q(NO3--N) was approximately 0.02 g ·(g ·h)-1. Microbial diversity was observed using MiSeq high-throughput sequencing. It showed that organic carbon had no significant effect on the abundance of Nitrosomomas and Candidutus_Kuenenia, while increasing the abundance of Candidutus_Brocadia and Denitratisoma in the sludge. This study provides ideas for the rapid start of continuous flow CANON granular sludge process to treat wastewater with low C/N ratio.


Assuntos
Nitrogênio , Esgotos , Processos Autotróficos , Reatores Biológicos , Desnitrificação , Nitritos , Oxirredução
9.
Huan Jing Ke Xue ; 41(4): 1794-1800, 2020 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608687

RESUMO

The effects of different hydraulic retention time (HRT) on short-cut nitrification granular sludge were studied in a continuous stirred-tank reactor (CSTR) by maintaining stable influent ammonia nitrogen load. Particle size distribution, extracellular polymeric substances (EPS), and functional bacterial kinetics were analyzed. The morphology of granular sludge, the performance of the CSTR, and the activity of functional microorganisms were investigated. The high throughout sequencing technology of MiSeq was employed to analyze the structure of the microbial community in sludge. The results showed that the ammonia nitrogen removal rate in the reactor was gradually increased from 80% to 95%, and the nitrite accumulation rate was always over 85% when the HRT was decreased from 4 h to 1 h. Particle size distribution of granular sludge was greatly influenced by HRT. The mass fraction of granules with a diameter smaller than 0.3 mm and larger than 1.6 mm was gradually declined, whereas the mass fraction of granules with a diameter between 0.3 mm and 0.8 mm was increased when HRT was shortened from 4 h to 1 h. The dominating proportion of granules with a diameter between 0.3 mm and 0.8 mm reached about 50% when HRT was 1 h. The impact of HRT on the activity of functional microorganisms was studied, and HRT activity was found to be closely related to the size of granular sludge. Proteobacteria were dominant in the system. AOB enrichment was represented by Nitrosomonas, which was more than 56%. Shortening HRT is beneficial for the enrichment of AOB.

10.
Huan Jing Ke Xue ; 41(1): 353-359, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854937

RESUMO

The rapid achievement of nitrifying micro-granular sludge and its nitritation function was studied in a continuously operated internal-loop airlift reactor seeding with floccular sludge. Results showed that the sludge micro-granulation was almost realized within three weeks by gradually reducing the hydraulic retention time from 5 h to 2.5 h. The color of the sludge first changed from yellowish-brown to creamy white, and then changed to pale yellow during the micro-granulation process. The settleability of the sludge first changed from good to bad, and then recovered to good. The value of the sludge settling velocity (SV) at SV5 and SV30 were both equal to 4%-5%, while SVI30 and SVI5 were both around 12-13 mL·g-1. The average size of the obtained nitrifying micro-granular sludge was 134 µm on day 27. Nearly 70% of the nitrifying micro-granular sludge was maintained in a relatively narrow range of 59-163 µm, thus indicating the largely homogeneous diameter distribution of these micro-granules. After sludge micro-granulation, the nitritation function was achieved within one week by progressively increasing the influent NH4 concentrations from 50 mg·L-1to 200 mg·L-1. The NO2- accumulation ratio and the nitritation loading rate reached up to 90% and 1.34 kg·(m3·d)-1, respectively. The high level of residual NH4 concentration in the effluent, or the low ratio of dissolved oxygen (DO) to NH4+-N concentrations (0.03-0.09), should be the primary cause of the rapid achievement of nitritation in the micro-granular sludge reactor.

11.
Huan Jing Ke Xue ; 40(10): 4578-4584, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854826

RESUMO

In order to apply partial nitritation-ANAMMOX (PN/A) technology to treat wastewater with high concentrations of ammonia, autotrophic nitrogen-removing granular sludge was crushed and inoculated into a three-stage continuous flow reactor. The nitrogen loading rate (NLR), dissolved oxygen (DO) concentration, and free ammonia (FA) levels in each compartment of the reactor were controlled over a 106-day period. Results showed that the nitritation process occurred with the inoculated granules during the initial phase. A limited aeration strategy was employed in the reactor at relatively high NLRs. Given the effective suppression of nitrite-oxidizing bacteria and the prevention of ANAMMOX bacteria from high DO conditions, the compact structure and nitrogen-removal activity of the granules could be improved. When the ammonia-nitrogen concentration was increased in the influent to 350 mg·L-1, the adverse impacts of high FA concentrations on the functional microbe activity in the first compartment should be eliminated. This occurs by reducing the influent pH and alkalinity dosage. This occurs by reducing the influent pH and degree of alkalinity. As a result, a total nitrogen removal rate of 7.2 kg·(m3·d)-1 was achieved in the reactor, which is 50 to 100 times higher than that of conventional activated sludge systems. The consistent improvement in the nitrogen-removal activity of the granules was demonstrated by batch testing at different aeration intensities. This showed that activity was greatest in the first compartment, which showed the highest granular maturity. In addition, a clear linear correlation (R2>0.97) was observed between the amount of extracellular polymeric substance and the specific nitrogen removal rate. This indicated that the dense granules played a positive role in enhancing the performance of the reactor.

12.
PLoS One ; 14(11): e0225755, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31765425

RESUMO

OBJECTIVE: The primary purpose of this study is to investigate the effect of hedgehog-interacting protein (HHIP) overexpression on the proliferation, migration and invasion of non-small cell lung cancer (NSCLC). METHODS: Firstly, HHIP gene expression data of NSCLC tissues and normal tissues were obtained from GSE18842/GSE19804/GSE43458 databases of the Gene Expression Omnibus (GEO) database and then validated by TCGA NSCLC database in a cohort of 1027 cases of NSCLC patients and 108 cases of normal people. A chi-square test was used to analyze the relationship between HHIP expression and clinicopathological characteristics of NSCLC. The expression levels of HHIP in NSCLC cells were detected by quantitative-real time PCR. The function of HHIP was investigated by a series of in vitro assays. CCK-8, wounding healing, Transwell invasion assay were utilized to explore the mechanisms of HHIP. RESULTS: HHIP mRNA were significantly down-regulated in NSCLC in three GEO databases and TCGA database (P<0.05). This result was confirmed in NSCLC cell lines by qRT-PCR analysis, its expression in normal NSCLC cell line BEAS-2B was significantly higher than that in NSCLC cells. Chi-square test results showed that the low expression of HHIP was correlated with gender, cancer type, TNM stage and tumor size. Functional experimental results showed that over-expressing HHIP significantly decreased the ability of cell proliferation, migration and invasion in NSCLC cells (P<0.05). CONCLUSION: Overall, the above results indicated that HHIP could regulate proliferation, migration and invasion, and could be used as a judging criterion for identifying NSCLC classification and stage.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Transporte/metabolismo , Proliferação de Células , Neoplasias Pulmonares/patologia , Glicoproteínas de Membrana/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Movimento Celular , Bases de Dados Factuais , Regulação para Baixo , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Estadiamento de Neoplasias
13.
Huan Jing Ke Xue ; 40(3): 1396-1404, 2019 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087990

RESUMO

The start-up and stable operation of single-stage autotrophic nitrogen removal process under low ammonia nitrogen substrate at room temperature appears as the premise and basis for the application in municipal wastewater treatment. In this study, the PN/A (partial nitritation and ANAMMOX) granular sludge for long-term storage was inoculated into an air-lift bioreactor to investigate the nitrogen removal performance during the start-up of single-stage partial nitritation and ANAMMOX process under the following conditions:temperature at (23±2)℃, pH at 7.7-8.0. Synthetic wastewater with ammonia nitrogen concentration of 70 mg·L-1 was used as influent. By stepwise shortening hydraulic retention time (HRT) (1.1 h→0.9 h→0.7 h→0.5 h) and increasing ammonia nitrogen loading rate[1.53 kg·(m3·d)-1→1.87 kg·(m3·d)-1→2.40 kg·(m3·d)-1→3.36 kg·(m3·d)-1], the bioactivity as the synergy between the ammonia oxidizing bacteria (AOB) and anaerobic oxidizing bacteria (AMX) were gradually restored. After 95 d operation and regulation, the process was successfully established and the removal rate of NH4+-N and TN were 85% and 69%, respectively. According to the performance of sludge at each stage, the nitrite oxidizing bacteria (NOB) were selectively inhibited by controlling dissolved oxygen strictly. The average particle size gradually increased and finally was reached to 1.30 mm after the sludge was adapted to the environment. The profile of the mature autotrophic granular sludge was smooth and clear, SEM showed that the center of granular sludge formed a cavity with porous structure on the surface, the sludge morphology consisted mainly of cocci, with a small amount of bacilli and short bacilli. The major component of EPS in granular sludge was protein (81.48%) indicating that it had a good settling performance.

14.
Huan Jing Ke Xue ; 39(4): 1756-1762, 2018 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965002

RESUMO

To obtain experimental evidences for optimizing a completely autotrophic nitrogen removal process based on granules, the effects of dissolved oxygen (DO) concentration, temperature (t), initial ammonium (NH4+-N) concentration, and solution pH conditions on the synergy between the aerobic and anaerobic ammonium-oxidizing bacteria (AOB and AMX) were investigated using a single factor batch experiment, while the analysis of the microbial community structure within them was conducted using MiSeq high-throughput pyrosequencing. Results revealed that AOB (genus Nitrosomonas) and AMX (genus Candidatus Kuenenia) dominated in the granules, representing relative abundances of 32.9% and 9.8%, respectively. For the granules, the highest specific nitrogen removal rate of q(TN)=(17.7±1.0) mg·(g·h)-1 was obtained at a DO concentration of 2 mg·L-1, while the initial NH4+-N concentration was set at 100 mg·L-1. And a lower DO level resulted in partial nitritation became the rate-limiting step of process, otherwise, it would be the ANAMMOX reaction instead. According to the free energy of the reactions, the activity of AMX was more sensitive to low temperature than that of AOB. When the reaction temperature was lower than 30℃, nitrite accumulation could be observed in bulk liquid, with the significant decrease of q(TN) for the granules. Under the same oxygen supply conditions, an initial NH4+-N concentration lower than 100 mg·L-1 could inhibit the activity of AMX partly. However, with an initial NH4+-N concentration over 150 mg·L-1, either oxygen-limiting or high free ammonia concentration could lead to the dramatic decrease of q(TN). In addition, the effective synergy of the two types of ammonium oxidizers in granules was always achieved at solution pH in the range of 7.0-8.5.


Assuntos
Bactérias/metabolismo , Reatores Biológicos/microbiologia , Nitrogênio/isolamento & purificação , Esgotos/microbiologia , Compostos de Amônio , Processos Autotróficos , Nitritos , Oxirredução , Oxigênio
15.
Huan Jing Ke Xue ; 39(12): 5580-5586, 2018 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-30628403

RESUMO

A two-stage partial nitritation (PN)-ANAMMOX process was successfully carried out for low-strength NH4+-N (50 mg·L-1) wastewater treatment at ambient/low temperatures. The results show that an average total nitrogen removal rate and removal efficiency above 0.6 kg·(m3·d)-1and 80% could be maintained, respectively, at temperatures between 20℃ and 14℃. The two-stage PN-ANAMMOX process was successful both under NO2--N-limited and NH4+-N-limited conditions. When the two-stage PN-ANAMMOX process was operated under NH4+-N-limited conditions, the "limit of technology" for nitrogen removal (TN<3 mg·L-1) could be easily achieved by following anoxic denitrification. Lowering the temperature to 12℃ resulted in the reduction of the total nitrogen removal rate to~0.5 kg·(m3·d)-1. Due to the low temperature, the anammox reaction became the rate-limiting step for nitrogen removal, while the PN reaction was not impacted. In the temperature range of 10-20℃, the activity-temperature coefficients (θ) of the PN granules and ANAMMOX sludge were 1.056 and 1.172, respectively, suggesting that the anammox bacteria have a higher temperature sensitivity than the ammonium oxidizing bacteria (AOB). Overall, the results clearly indicate that the nitrogen removal loading rate of the two-stage PN-ANAMMOX process is mainly controlled by the activity and quantity of anammox biomass. In contrast, the process nitrogen removal efficiency mainly depends on the performance of the first-stage PN (i.e., effluent NO2--N/NH4+-N ratio and NO3--N concentration) under a constant nitrogen removal loading rate (no overload). Based on these results, a hierarchically separate control strategy was proposed to obtain a high-rate nitrogen removal during the two-stage mainstream PN-ANAMMOX process.


Assuntos
Desnitrificação , Nitrogênio/isolamento & purificação , Compostos de Amônio , Bactérias , Reatores Biológicos/microbiologia , Oxirredução , Esgotos , Águas Residuárias , Purificação da Água
16.
Inorg Chem ; 56(5): 2367-2370, 2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-28186410

RESUMO

Herein we report the construction of a supramolecular cocrystal {Ti4 + Ti6} through the combination of isolated {Ti4} and {Ti6} clusters. Moreover, the combined {Ti4 + Ti6} complex presents better solar-driven photocatalytic dye degradation activity than the individual {Ti4} and {Ti6} compounds.

17.
Huan Jing Ke Xue ; 38(1): 269-275, 2017 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965056

RESUMO

To explore the short-term impact of biodegradable organic matter on the activities of different functional microbes in autotrophic partial nitrification granular sludge (PNG),the variations of both nitrogen transformation performance and dissolved oxygen (DO) uptake of PNG were investigated in this study,by carrying out successive batch tests with and without the organics stressing.The results showed that the higher the C/N ratio,the lower the specific nitrite accumulation rate of q(NO2--N).Meanwhile,the increase of heterotrophic bacteria (HeB) activities caused the fast DO uptake by PNG,which could effectively suppress nitrite oxidizing bacteria (NOB) with the low oxygen affinity.When inorganic substrate culture was employed in the following phase,both HeB and NOB showed low activities,with significant increase in q(NO2--N).In short,the adverse effects of biodegradable organic matter on the performance of PNG system were partially reversible,which could benefit to enhance the advantage of ammonium oxidizing bacteria (AOB) and improve the stability of partial nitrification reaction.


Assuntos
Reatores Biológicos/microbiologia , Nitrificação , Esgotos/microbiologia , Amônia/química , Nitritos/química , Oxirredução
18.
Huan Jing Ke Xue ; 38(9): 3787-3792, 2017 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965260

RESUMO

In order to examine the continuous growth capacity of the nitrosation granular sludge (NGS), the sludge was inoculated to start up the columnar sequencing batch reactor (SBR). During 130 d, the concentration of mixed liquor suspended solids (MLSS) in SBR increased from 0.1 g·L-1 to 11.8 g·L-1, corresponding to the nitrite-nitrogen accumulation rate of 0.4-4.9 kg·(m3·d)-1, promoted by a higher ammonia-nitrogen loading rate (NLR) from 0.74 kg·(m3·d)-1 to 6.66 kg·(m3·d)-1in the influent. Because of the obvious increase in small granules (size<200 µm), the mean average diameter of NGS decreased significantly at NLR<4.44 kg·(m3·d)-1. At higher NLR values, the growth of the mean average diameter of NGS could be fitted well using a modified logistic model. The specific growth rate of the k value was 0.0229 d-1. In addition, the combined inhibition of nitrite oxidizing bacteria (NOB) was expected at relatively high concentrations of both free ammonia (FA) and free nitrite acid (FNA); thus, the nitrite accumulation ratio (NAR) in the effluent was always higher than 80%. These results provide a feasible approach to start up a high-performance NGS reactor at the industrial-scale.


Assuntos
Bactérias/metabolismo , Reatores Biológicos , Nitritos/metabolismo , Nitrosação , Esgotos , Amônia , Nitrogênio , Eliminação de Resíduos Líquidos
19.
J BUON ; 21(5): 1332, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27837645

RESUMO

In the version of this article initially published, in Volume 21, issue 3, the first affiliation (affiliation number 1) was incorrectly stated as "Department of Pathology, Faculty of Medicine, Adnan Menderes University, Aydin, Turkey". The correct affiliation is "Department of Oncology, Shaoxing People's Hospital ,Shaoxing Hospital of Zhejiang University, Shaoxing 312000,China'. This error appeared only in the PubMed database and not in the print form of the Journal.

20.
Huan Jing Ke Xue ; 37(4): 1478-84, 2016 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-27548972

RESUMO

To explore the potential stressing effect of nanoscale zero-valent iron (nZVI) on denitrifying granular sludge (DGS), the evolution of DGS denitrifying performance under different C/N ratios was investigated in this study, by carrying out batch tests of eight successive periods with the nZVI shock-loading. The results showed that the specific denitrification rate of µ value decreased when the nZVI dosage was higher than 5 mg · L⁻¹. Meanwhile, a positive correlation between the inhibition ratio (IR) of µ value and substrate C/N ratios or nZVI dosage was observed. When the nZVI dosage reached 100 mg · L⁻¹, both extracellular protein and polysaccharides concentrations decreased obviously. It would be beneficial to promote the recovery of DGS denitrifying activity and reduce the COD demanding to remove unit mass of nitrate, by increasing external carbon source with C/N ratios of higher than 4. On the basis of Freundlich and Langmuir adsorption isotherms, when higher C/N ratio was provided, stronger bioadsorption of nZVI would be achieved. During the recovery period, a significant improvement of DCS denitrifying performance under the high C/N ratio was expected, due to the continuous washout of total iron in sludge phase (Qe), while the µ value would reach or approach the one of the control group when Qe was lower than 0.4 mg · g⁻¹.


Assuntos
Desnitrificação , Ferro/química , Nitratos/isolamento & purificação , Esgotos/química , Adsorção , Análise da Demanda Biológica de Oxigênio , Carbono/análise , Nitrogênio/análise
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