Pub Date : 2023-09-28DOI: 10.1017/s0885715623000349
Stephanie Jennings
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{"title":"72nd Annual Denver X-ray Conference Report","authors":"Stephanie Jennings","doi":"10.1017/s0885715623000349","DOIUrl":"https://doi.org/10.1017/s0885715623000349","url":null,"abstract":"An abstract is not available for this content so a preview has been provided. Please use the Get access link above for information on how to access this content.","PeriodicalId":20333,"journal":{"name":"Powder Diffraction","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135386797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-28DOI: 10.1017/s0885715623000350
Paweł Adamski, Aleksander Albrecht, Dariusz Moszyński
A new compound NH 4 Co 2 OH(MoO 4 ) 2 ⋅H 2 O was prepared by precipitation of aqueous solutions of cobalt nitrate and ammonium heptamolybdate at pH = 7.5. The crystal structure was identified by X-ray powder diffraction (XRPD) and Rietveld refinement as a known polymorph of layered molybdates (Φ y ) with general formula AT 2 OH(MoO 4 ) 2 ⋅H 2 O ( A = NH 4 + , Na + , K + and T = Zn 2+ , Co 2+ , Cu 2+ , Ni 2+ ) and refined from a model based on that structure. The lattice parameters were refined with R- 3 space group (148) a = 6.1014(2) Å, b = 6.1014(2) Å, c = 21.826(1) Å, α = 90°, β = 90°, and γ = 120°.
以硝酸钴和七钼酸铵水溶液为原料，在pH = 7.5的条件下进行沉淀，得到了一种新的化合物nh4 Co 2 OH(moo4) 2⋅H 2o。通过x射线粉末衍射(XRPD)和Rietveld细化鉴定，该晶体结构为已知的层状钼酸盐(Φ y)多晶型，通式为AT 2 OH(MoO 4) 2⋅H 2 O (a = NH 4 +， Na +， K +， T = Zn 2+， Co 2+， Cu 2+， Ni 2+)，并基于该结构建立了模型。晶格参数细化为R- 3空间群(148)a = 6.1014(2) Å， b = 6.1014(2) Å， c = 21.826(1) Å， α = 90°，β = 90°，γ = 120°。
{"title":"Synthesis and crystal structure of layered molybdate NH<sub>4</sub>Co<sub>2</sub>OH(MoO<sub>4</sub>)<sub>2</sub>⋅H<sub>2</sub>O","authors":"Paweł Adamski, Aleksander Albrecht, Dariusz Moszyński","doi":"10.1017/s0885715623000350","DOIUrl":"https://doi.org/10.1017/s0885715623000350","url":null,"abstract":"A new compound NH 4 Co 2 OH(MoO 4 ) 2 ⋅H 2 O was prepared by precipitation of aqueous solutions of cobalt nitrate and ammonium heptamolybdate at pH = 7.5. The crystal structure was identified by X-ray powder diffraction (XRPD) and Rietveld refinement as a known polymorph of layered molybdates (Φ y ) with general formula AT 2 OH(MoO 4 ) 2 ⋅H 2 O ( A = NH 4 + , Na + , K + and T = Zn 2+ , Co 2+ , Cu 2+ , Ni 2+ ) and refined from a model based on that structure. The lattice parameters were refined with R- 3 space group (148) a = 6.1014(2) Å, b = 6.1014(2) Å, c = 21.826(1) Å, α = 90°, β = 90°, and γ = 120°.","PeriodicalId":20333,"journal":{"name":"Powder Diffraction","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135386977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To address the issues with inadequate search space, sluggish convergence and easy fall into local optimality during iteration of the sparrow search algorithm (SSA), a multi-strategy improved sparrow search algorithm (ISSA), is developed. First, the population dynamic adjustment strategy is carried out to restrict the amount of sparrow population discoverers and joiners. Second, the update strategy in the mining phase of the honeypot optimization algorithm (HBA) is combined to change the update formula of the joiner's position to enhance the global exploration ability of the algorithm. Finally, the optimal position of population discoverers is perturbed using the perturbation operator and levy flight strategy to improve the ability of the algorithm to jump out of local optimum. The experimental simulations are put up against the basic sparrow search algorithm and the other four swarm intelligence (SI) algorithms in 13 benchmark test functions, and the Wilcoxon rank sum test is used to determine whether the algorithm is significantly different from the other algorithms. The results show that the improved sparrow search algorithm has better convergence and solution accuracy, and the global optimization ability is greatly improved. When the proposed algorithm is used in pilot optimization in channel estimation, the bit error rate is greatly improved, which shows the superiority of the proposed algorithm in engineering application.
{"title":"Research on multi-strategy improved sparrow search optimization algorithm.","authors":"Teng Fei, Hongjun Wang, Lanxue Liu, Liyi Zhang, Kangle Wu, Jianing Guo","doi":"10.3934/mbe.2023767","DOIUrl":"10.3934/mbe.2023767","url":null,"abstract":"<p><p>To address the issues with inadequate search space, sluggish convergence and easy fall into local optimality during iteration of the sparrow search algorithm (SSA), a multi-strategy improved sparrow search algorithm (ISSA), is developed. First, the population dynamic adjustment strategy is carried out to restrict the amount of sparrow population discoverers and joiners. Second, the update strategy in the mining phase of the honeypot optimization algorithm (HBA) is combined to change the update formula of the joiner's position to enhance the global exploration ability of the algorithm. Finally, the optimal position of population discoverers is perturbed using the perturbation operator and levy flight strategy to improve the ability of the algorithm to jump out of local optimum. The experimental simulations are put up against the basic sparrow search algorithm and the other four swarm intelligence (SI) algorithms in 13 benchmark test functions, and the Wilcoxon rank sum test is used to determine whether the algorithm is significantly different from the other algorithms. The results show that the improved sparrow search algorithm has better convergence and solution accuracy, and the global optimization ability is greatly improved. When the proposed algorithm is used in pilot optimization in channel estimation, the bit error rate is greatly improved, which shows the superiority of the proposed algorithm in engineering application.</p>","PeriodicalId":20333,"journal":{"name":"Powder Diffraction","volume":"36 1","pages":"17220-17241"},"PeriodicalIF":2.6,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70218441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.1017/s0885715623000416
An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the ‘Save PDF’ action button.
{"title":"PDJ volume 38 issue 3 Cover and Back matter","authors":"","doi":"10.1017/s0885715623000416","DOIUrl":"https://doi.org/10.1017/s0885715623000416","url":null,"abstract":"An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the ‘Save PDF’ action button.","PeriodicalId":20333,"journal":{"name":"Powder Diffraction","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135782658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.1017/s0885715623000246
James A. Kaduk, Nilan V. Patel, Joseph T. Golab
The crystal structure of L-5-methyltetrahydrofolate calcium trihydrate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Calcium levomefolate trihydrate crystallizes in space group P 2 1 2 1 2 1 (#19) with a = 7.1706(6), b = 6.5371(5), c = 53.8357(41) Å, V = 2523.58(26) Å 3 , and Z = 4. The structure is characterized by alternating hydrophobic and hydrophilic layers along the c -axis. The Ca cations are 7-coordinate, and share edges to form chains along the b -axis. Each of the water molecules acts as a donor in two hydrogen bonds. The coordinated water molecule makes two strong intermolecular O–H⋯O hydrogen bonds to carboxyl and carbonyl groups. The two zeolitic water molecules form weaker hydrogen bonds, to carbonyl O atoms, ring N atoms, and aromatic C atoms. Several N–H⋯O/N hydrogen bonds, as well as C–H⋯O hydrogen bonds, also contribute to the lattice energy.
利用同步加速器x射线粉末衍射数据对l -5-甲基四氢叶酸三水合钙的晶体结构进行了解析和细化，并利用密度函数技术对其进行了优化。三水合左旋叶酸钙在空间群p21 1 2 1 21 1(#19)中结晶，a = 7.1706(6)， b = 6.5371(5)， c = 53.8357(41) Å， V = 2523.58(26) Å 3, Z = 4。该结构的特点是沿c轴有疏水层和亲水层交替存在。Ca阳离子为7坐标，沿b轴共享边形成链。每个水分子在两个氢键中充当供体。配位的水分子与羧基和羰基形成两个强的O - h⋯O氢键。这两个沸石水分子与羰基O原子、环N原子和芳香C原子形成较弱的氢键。几个N - h⋯O/N氢键，以及C-H⋯O氢键，也有助于晶格能量。
{"title":"Crystal structure of calcium L-5-methyltetrahydrofolate trihydrate type I, C<sub>20</sub>H<sub>23</sub>N<sub>7</sub>O<sub>6</sub>Ca(H<sub>2</sub>O)<sub>3</sub>","authors":"James A. Kaduk, Nilan V. Patel, Joseph T. Golab","doi":"10.1017/s0885715623000246","DOIUrl":"https://doi.org/10.1017/s0885715623000246","url":null,"abstract":"The crystal structure of L-5-methyltetrahydrofolate calcium trihydrate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Calcium levomefolate trihydrate crystallizes in space group P 2 1 2 1 2 1 (#19) with a = 7.1706(6), b = 6.5371(5), c = 53.8357(41) Å, V = 2523.58(26) Å 3 , and Z = 4. The structure is characterized by alternating hydrophobic and hydrophilic layers along the c -axis. The Ca cations are 7-coordinate, and share edges to form chains along the b -axis. Each of the water molecules acts as a donor in two hydrogen bonds. The coordinated water molecule makes two strong intermolecular O–H⋯O hydrogen bonds to carboxyl and carbonyl groups. The two zeolitic water molecules form weaker hydrogen bonds, to carbonyl O atoms, ring N atoms, and aromatic C atoms. Several N–H⋯O/N hydrogen bonds, as well as C–H⋯O hydrogen bonds, also contribute to the lattice energy.","PeriodicalId":20333,"journal":{"name":"Powder Diffraction","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135782657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.1017/s0885715623000398
An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the ‘Save PDF’ action button.
{"title":"PDJ volume 38 issue 3 Cover and Front matter","authors":"","doi":"10.1017/s0885715623000398","DOIUrl":"https://doi.org/10.1017/s0885715623000398","url":null,"abstract":"An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the ‘Save PDF’ action button.","PeriodicalId":20333,"journal":{"name":"Powder Diffraction","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135782659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.1017/s0885715623000234
Gang Wang
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{"title":"Calendar of Short Courses and Workshops","authors":"Gang Wang","doi":"10.1017/s0885715623000234","DOIUrl":"https://doi.org/10.1017/s0885715623000234","url":null,"abstract":"An abstract is not available for this content. As you have access to this content, full HTML content is provided on this page. A PDF of this content is also available in through the ‘Save PDF’ action button.","PeriodicalId":20333,"journal":{"name":"Powder Diffraction","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135782656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-10DOI: 10.1017/s0885715623000271
Tawnee M. Ens, J. Kaduk, A. Došen, T. Blanton
The crystal structure of danofloxacin mesylate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Danofloxacin mesylate crystallizes in space group P1 (#1) with a = 6.77474(8), b = 12.4973(4), c = 12.82826(28) Å, α = 84.8709(29), β = 87.7501(10), γ = 74.9916(4)°, V = 1044.723(11) Å3, and Z = 2. The protonation of the danofloxacin cations was established by the analysis of potential intermolecular interactions and differs from that expected from isolated-cation calculations. The crystal structure consists of alternating layers of cations and anions parallel to the ac-plane. There is parallel stacking of the oxoquinoline rings along the a-axis. The expected N–H⋯O hydrogen bonds between the cations and anions are not present. Each cation makes an N–H⋯O hydrogen bond with the other cation, resulting in zig-zag chains along the a-axis. Both cations have strong intramolecular O–H⋯O hydrogen bonds. There are several C–H⋯O hydrogen bonds between the danofloxacin cations and mesylate anions. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).
利用同步x射线粉末衍射数据对甲磺酸丹诺氟沙星的晶体结构进行了解析和细化，并利用密度泛函理论技术对其进行了优化。甲磺酸达诺氟沙星在P1(#1)空间群中结晶，a = 6.77474(8)， b = 12.4973(4)， c = 12.82826(28) Å， α = 84.8709(29)， β = 87.7501(10)， γ = 74.9916(4)°，V = 1044.723(11) Å3, Z = 2。丹氧氟沙星阳离子的质子化是通过分析潜在的分子间相互作用确定的，与分离阳离子计算的结果不同。晶体结构由平行于ac平面的阳离子和阴离子交替层组成。氧喹啉环沿a轴平行堆叠。阳离子和阴离子之间预期的N-H⋯O氢键不存在。每个阳离子与另一个阳离子形成一个N-H⋯O氢键，形成沿着a轴的锯齿形链。两种阳离子都具有很强的分子内O - h⋯O氢键。danoflo沙星阳离子和甲磺酸阴离子之间有几个C-H⋯O氢键。粉末图案已提交给ICDD®，纳入粉末衍射文件™(PDF®)。
{"title":"Crystal structure of danofloxacin mesylate (C19H21FN3O3)(CH3O3S)","authors":"Tawnee M. Ens, J. Kaduk, A. Došen, T. Blanton","doi":"10.1017/s0885715623000271","DOIUrl":"https://doi.org/10.1017/s0885715623000271","url":null,"abstract":"The crystal structure of danofloxacin mesylate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Danofloxacin mesylate crystallizes in space group P1 (#1) with a = 6.77474(8), b = 12.4973(4), c = 12.82826(28) Å, α = 84.8709(29), β = 87.7501(10), γ = 74.9916(4)°, V = 1044.723(11) Å3, and Z = 2. The protonation of the danofloxacin cations was established by the analysis of potential intermolecular interactions and differs from that expected from isolated-cation calculations. The crystal structure consists of alternating layers of cations and anions parallel to the ac-plane. There is parallel stacking of the oxoquinoline rings along the a-axis. The expected N–H⋯O hydrogen bonds between the cations and anions are not present. Each cation makes an N–H⋯O hydrogen bond with the other cation, resulting in zig-zag chains along the a-axis. Both cations have strong intramolecular O–H⋯O hydrogen bonds. There are several C–H⋯O hydrogen bonds between the danofloxacin cations and mesylate anions. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).","PeriodicalId":20333,"journal":{"name":"Powder Diffraction","volume":" ","pages":""},"PeriodicalIF":0.5,"publicationDate":"2023-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46659682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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