, but this code // executes before the first paint, when

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is not yet present. The // classes are added to so styling immediately reflects the current // toolbar state. The classes are removed after the toolbar completes // initialization. const classesToAdd = ['toolbar-loading', 'toolbar-anti-flicker']; if (toolbarState) { const { orientation, hasActiveTab, isFixed, activeTray, activeTabId, isOriented, userButtonMinWidth } = toolbarState; classesToAdd.push( orientation ? `toolbar-` + orientation + `` : 'toolbar-horizontal', ); if (hasActiveTab !== false) { classesToAdd.push('toolbar-tray-open'); } if (isFixed) { classesToAdd.push('toolbar-fixed'); } if (isOriented) { classesToAdd.push('toolbar-oriented'); } if (activeTray) { // These styles are added so the active tab/tray styles are present // immediately instead of "flickering" on as the toolbar initializes. In // instances where a tray is lazy loaded, these styles facilitate the // lazy loaded tray appearing gracefully and without reflow. const styleContent = ` .toolbar-loading #` + activeTabId + ` { background-image: linear-gradient(rgba(255, 255, 255, 0.25) 20%, transparent 200%); } .toolbar-loading #` + activeTabId + `-tray { display: block; box-shadow: -1px 0 5px 2px rgb(0 0 0 / 33%); border-right: 1px solid #aaa; background-color: #f5f5f5; z-index: 0; } .toolbar-loading.toolbar-vertical.toolbar-tray-open #` + activeTabId + `-tray { width: 15rem; height: 100vh; } .toolbar-loading.toolbar-horizontal :not(#` + activeTray + `) > .toolbar-lining {opacity: 0}`; const style = document.createElement('style'); style.textContent = styleContent; style.setAttribute('data-toolbar-anti-flicker-loading', true); document.querySelector('head').appendChild(style); if (userButtonMinWidth) { const userButtonStyle = document.createElement('style'); userButtonStyle.textContent = `#toolbar-item-user {min-width: ` + userButtonMinWidth +`px;}` document.querySelector('head').appendChild(userButtonStyle); } } } document.querySelector('html').classList.add(...classesToAdd); })(); Clarence Menninga | 麻豆区

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Dr. Clarence Menninga

Professor Emeritus

Biography

  • Hometown: Pella, IA
  • Now lives in Grand Rapids with his wife Irene

Current activities

  • Teaching: a course for senior citizens on occasion
  • Hosts guests at the Dice Mineralogical Museum by arrangement
  • Gives department seminar talks from time to time
  • Presents a program for various adult groups now and then on topics related to geology or to the relationship between science and Christian faith.
  • Enjoys playing recreational golf

Education

  • Completed a B.A. in Chemistry at Calvin College, 1949
  • Received his M.A.T. in science and math at Western Michigan University, 1959
  • Received his PhD in Chemistry from Purdue University, 1965

Professional Experience

  • Worked as an anayltical Chemist for a while
  • Taught at Grand Rapids Christian High School
  • Worked briefly at Lawrence Radiation Laboratory in Livermore, CA
  • Joined the Calvin College Faculty in 1967 as a full-time Professor, hired to develop courses and programs in Earth Science and Geology.
  • Retired in 1990

Academic Interests

  • Meteorites
  • Science and Christian faith relationships